Rc Fuel Faq
01-25-2002, 02:43 AM
#1
Rc Fuel Faq
The RCU Administrator felt it would be a good idea to have a Frequently Asked Questions area in this forum. What I will attempt to do is make this particular FAQ area somewhat of a refrence page to some of the more often asked questions I've heard concerning fuel. I will do this without intent to insult, inflame or otherwise upset anybody. Quite a bit of mis-information, half truths and incomplete information about glow fuels circulates at the flying fields. Much of this information does little more than confuse the modeler trying to learn about the fuel their engines need. Regardless of what the "club guru" says, I will present the facts as best I can and when necessary contact other experts concerning a particular subject. I will not bash one product or praise another- please do not supply the administrator with questions in which a side has to be taken in order to answer.
Q: What makes my glow fuel go bad?
A: A couple of things can and will contribute to a glow fuel "going bad" First, lets talk about how you should store it; Fuel should never be opened untill you're ready to start using it, and after its opened it should have its exposure to the atmosphere limited as much as possible. This is because the methanol (alcohol) in our fuel is hygroscopic, which means it will soak up water like a sponge- even out of the air! To help limit the exposure, especially in warmer humid climates, once open and at the field, devise a system to block off or cap your vents to the bottle. Don't leave the vents open if you use a pump or something similar, air (and humidity) will pass through an open vent and the fuel is more exposed. Water in the fuel is not a good thing, if it gets exposed to air, it can get water in it.
Next, while storing fuel, it is important to limit the sunlight it is exposed to. During storage, for obvious reasons a cool dry DARK place is the best way to go. Nitromethane, one component that most of us have in our fuel, will for the lack of a better term degrade when exposed to sunlight. I'm not going to get technical here with the chemical reaction specifics, but limit the sunlight exposure to fuels containing nitro. But what about a trip to the field? Yes, it gets exposed to moisture (through the air) and to sunlight! So lets keep it simple: keep the lines pluged and toss a light colored cloth over the bottle so that it is shaded.
If your are a large glow fuel user, say a gallon per weekend or day, is this something to get concerned about- probably not. However if you are a less frequent flier and that gallon of fuel will last you many trips to the field, all this may help you keep your fuel as fresh as possible.
As a sidebar to this question, I have been asked numerous times if glow fuel has a shelf life. The answer is that I can not find any evidence to support weather it does or does not when it is kept unopened and tightly capped in a cool dry place. Once opened it can be a whole new ball game.
Below is a post that I will address one line item at a time. This may take a day or two to get it all together, so come on back and we'll have some answers for you.
A few more (taken from an e-mail by a new modeler)
Q: Can I add xxWxx motor oil to the fuel?- Why or why not?
A: Update to the previous answer; I actually tried mixing up a test blend and found that the generic motor oil will not stay in solution with the methanol and nitromethane. I called up Dave Geirke and he verified the fact.
Q: How come my fuel doesn't contain 2 stroke oil for my 2 stroke engine.
A: IT DOES!!! your glow fuel is designed with 2-stroke oils- the best ones out there for use in an alcohol based fuel. They are Castor oil and Synthetic Castors. Castor oil has been lubricating gasoline and alcohol based fuels since the internal combustion engine became viable. Widely used in WW I as the 2 stroke oil of choice in the rotary engines of the biplanes of the day. The 2-stroke oils you see on the shelf at the store for weed eaters and such will not work for our applications: that oil is designed to be used in gasoline in engines designed a little bit differently.
Q: Since I already left an open container of fuel out for two days in my garage should or could I use a commercial fuel stabilizer, say like the ones available to boat owners for winter storage?
A: Once glow fuel has absorbed water, its there for good for all practical purposes. The only way I know of getting absorbed water out of methanol is to use a molecular seive, something I have very little experience with. As far as fuel stabilizers go, they are designed to keep the gasoline from breaking down and turning into varnish and gumming up your boat, mower etc during long term storage. They will not absorb water, that is not the intended purpose of the stabalizer. This will not solve a glow fuel problem. If you are in a very humid area, the fuel will absorb much more water than in a dry arid climate. Run your fuel in your engine and decide if the fuel has been contaminated enough to warrant purchasing a new bottle. Keep your containers caped and in a cool dry dark place when not in use.
Q: If I add more castor oil to the fuel, will it reduce the fuels octane? or overall energy output?
A: If you add more anything to your jug of fuel, it will change the ratios of all other ingredients. For instance, you add 3 oz of castor to a new gallon of fuel, now that gallon is 131 oz, not 128. Your other ingredients are not added in proper proportion so they actually drop as a percentage of the whole. Will it hurt anything- probably not. The energy out put as you term it will be affected but if you even can notice it, it'll be a negledgable amount and not worth worring about especially since the engine will be happier.
Q: Why is it PINK?
A: Most fuel manufacturers use a dye in the finished product for a number of different reasons: Product Identity, different blends such as different uses or nitro contents. Allow the user to see how much is in his tank (important for heli's)
Q: What is the best oil ratio (castor to synthetic) mix for breaking in my xxx type engine.
A: I can see this question opening up a can of worms. Seems everybody has an opinion on the great ongoing debate of castor or synthetics.
In days of old, castor was the oil of choice with the lapped iron piston and sleeve engines and still is. Today, not as many engines are of that piston and sleeve metalurgy. Most today are either ringed piston in a steel or chrome sleeve or of an interference fit type commonly called ABC/ABN or AAC. In either type of the most modern offerings, too much oil will never hurt anything. I have, and always will recommend a minimum of 20% oil to all my customers with airplane or boat engines. Now too much castor will not hurt anything during the first gallon in any engine (break in period), after that feed your engine according to type. Ie: You're going to feed a ringed engine or an ABC type engine and in some cases a lapped iron engine.
In the ringed engines after break in (both two and four stroke) use 20% total oil with a little bit of castor (2% works great) and 18% synthetic. This is my prefered choice for any ringed engine since it is enough castor to help protect the rod journals and rust prevention on the bearings without being too much to gum up the ring after many many gallons. This holdes true for 4-strokes as well.
In ABC type engines, use more castor to offer greater scuff protection, I recommend 20% total oil with 4% of that being castor and 16% synthetic.
In lapped iron type engines such as the lapped Fox control line engines and the Fox 40 lapped engine, I recommend a very high content of castor for break in such as 29% all castor. After a thorough break in, some guys like to back down to 20% to 22% total oil with at least 50% of the oil content being castor.
Q: What is the best recipie for speed/ reliability?
A: Speed and reliability are two totally different subjects if you're refering to racing.
Obviously if you cut down on oil, your burnable components are increased, namely the methanol. Some racing fuels on the market contain less than 16% total oil and some racers have mixed up fuel with very little oil such as 4-6%, all in an effort to get the extra edge. Fuel with low oil is great for speed but longevity will diminish rapidly. All out competition racers expect to win races at the cost of racing engines.
If you want to run your sport XX46XX engine with a competition type low oil fuel in an effort to gain more performance, you may in fact ruin it. If you want a high performance engine, buy a Nelson, Jett, Rossi, MVVS or a couple others. Most these engines makers offer a sport style engine that is very high in performance. But keep in mind that even these high performance "sport" engines require a higher oil content that what competition fules usually have.
The overall answer is if you want to go faster, buy a faster engine, but you still need to properly feed it. No such sport recipies exist.
I have made fuel to compare the performance gain by cutting down the oil content. On a Super Tiger 75, my traditional 20% ringed engine oil blend at 15% nitro only turned 40 rpms less than a fuel with 17% oil. Is that a significant amount?- definatly not! however, the down side was that the lower oil fuel ran 38 degrees hotter at the maximum rpm. That's Significant!!!!
Q: What type of glow plug works best with xx% of fuel.
A: General rule of thumb:
High nitro fuels need a colder plug and,
Lower nitro fuels need a hotter plug.
4-strokes need 4-stroke plugs, they are very hot.
Heli's usually fly hot plugs.
I have compiled a list of some common plugs and catagorized it by heat range as specified by the manufacturer. e-mail me if you want a copy.
Fuelman
__________________
Q: What makes my glow fuel go bad?
A: A couple of things can and will contribute to a glow fuel "going bad" First, lets talk about how you should store it; Fuel should never be opened untill you're ready to start using it, and after its opened it should have its exposure to the atmosphere limited as much as possible. This is because the methanol (alcohol) in our fuel is hygroscopic, which means it will soak up water like a sponge- even out of the air! To help limit the exposure, especially in warmer humid climates, once open and at the field, devise a system to block off or cap your vents to the bottle. Don't leave the vents open if you use a pump or something similar, air (and humidity) will pass through an open vent and the fuel is more exposed. Water in the fuel is not a good thing, if it gets exposed to air, it can get water in it.
Next, while storing fuel, it is important to limit the sunlight it is exposed to. During storage, for obvious reasons a cool dry DARK place is the best way to go. Nitromethane, one component that most of us have in our fuel, will for the lack of a better term degrade when exposed to sunlight. I'm not going to get technical here with the chemical reaction specifics, but limit the sunlight exposure to fuels containing nitro. But what about a trip to the field? Yes, it gets exposed to moisture (through the air) and to sunlight! So lets keep it simple: keep the lines pluged and toss a light colored cloth over the bottle so that it is shaded.
If your are a large glow fuel user, say a gallon per weekend or day, is this something to get concerned about- probably not. However if you are a less frequent flier and that gallon of fuel will last you many trips to the field, all this may help you keep your fuel as fresh as possible.
As a sidebar to this question, I have been asked numerous times if glow fuel has a shelf life. The answer is that I can not find any evidence to support weather it does or does not when it is kept unopened and tightly capped in a cool dry place. Once opened it can be a whole new ball game.
Below is a post that I will address one line item at a time. This may take a day or two to get it all together, so come on back and we'll have some answers for you.
A few more (taken from an e-mail by a new modeler)
Q: Can I add xxWxx motor oil to the fuel?- Why or why not?
A: Update to the previous answer; I actually tried mixing up a test blend and found that the generic motor oil will not stay in solution with the methanol and nitromethane. I called up Dave Geirke and he verified the fact.
Q: How come my fuel doesn't contain 2 stroke oil for my 2 stroke engine.
A: IT DOES!!! your glow fuel is designed with 2-stroke oils- the best ones out there for use in an alcohol based fuel. They are Castor oil and Synthetic Castors. Castor oil has been lubricating gasoline and alcohol based fuels since the internal combustion engine became viable. Widely used in WW I as the 2 stroke oil of choice in the rotary engines of the biplanes of the day. The 2-stroke oils you see on the shelf at the store for weed eaters and such will not work for our applications: that oil is designed to be used in gasoline in engines designed a little bit differently.
Q: Since I already left an open container of fuel out for two days in my garage should or could I use a commercial fuel stabilizer, say like the ones available to boat owners for winter storage?
A: Once glow fuel has absorbed water, its there for good for all practical purposes. The only way I know of getting absorbed water out of methanol is to use a molecular seive, something I have very little experience with. As far as fuel stabilizers go, they are designed to keep the gasoline from breaking down and turning into varnish and gumming up your boat, mower etc during long term storage. They will not absorb water, that is not the intended purpose of the stabalizer. This will not solve a glow fuel problem. If you are in a very humid area, the fuel will absorb much more water than in a dry arid climate. Run your fuel in your engine and decide if the fuel has been contaminated enough to warrant purchasing a new bottle. Keep your containers caped and in a cool dry dark place when not in use.
Q: If I add more castor oil to the fuel, will it reduce the fuels octane? or overall energy output?
A: If you add more anything to your jug of fuel, it will change the ratios of all other ingredients. For instance, you add 3 oz of castor to a new gallon of fuel, now that gallon is 131 oz, not 128. Your other ingredients are not added in proper proportion so they actually drop as a percentage of the whole. Will it hurt anything- probably not. The energy out put as you term it will be affected but if you even can notice it, it'll be a negledgable amount and not worth worring about especially since the engine will be happier.
Q: Why is it PINK?
A: Most fuel manufacturers use a dye in the finished product for a number of different reasons: Product Identity, different blends such as different uses or nitro contents. Allow the user to see how much is in his tank (important for heli's)
Q: What is the best oil ratio (castor to synthetic) mix for breaking in my xxx type engine.
A: I can see this question opening up a can of worms. Seems everybody has an opinion on the great ongoing debate of castor or synthetics.
In days of old, castor was the oil of choice with the lapped iron piston and sleeve engines and still is. Today, not as many engines are of that piston and sleeve metalurgy. Most today are either ringed piston in a steel or chrome sleeve or of an interference fit type commonly called ABC/ABN or AAC. In either type of the most modern offerings, too much oil will never hurt anything. I have, and always will recommend a minimum of 20% oil to all my customers with airplane or boat engines. Now too much castor will not hurt anything during the first gallon in any engine (break in period), after that feed your engine according to type. Ie: You're going to feed a ringed engine or an ABC type engine and in some cases a lapped iron engine.
In the ringed engines after break in (both two and four stroke) use 20% total oil with a little bit of castor (2% works great) and 18% synthetic. This is my prefered choice for any ringed engine since it is enough castor to help protect the rod journals and rust prevention on the bearings without being too much to gum up the ring after many many gallons. This holdes true for 4-strokes as well.
In ABC type engines, use more castor to offer greater scuff protection, I recommend 20% total oil with 4% of that being castor and 16% synthetic.
In lapped iron type engines such as the lapped Fox control line engines and the Fox 40 lapped engine, I recommend a very high content of castor for break in such as 29% all castor. After a thorough break in, some guys like to back down to 20% to 22% total oil with at least 50% of the oil content being castor.
Q: What is the best recipie for speed/ reliability?
A: Speed and reliability are two totally different subjects if you're refering to racing.
Obviously if you cut down on oil, your burnable components are increased, namely the methanol. Some racing fuels on the market contain less than 16% total oil and some racers have mixed up fuel with very little oil such as 4-6%, all in an effort to get the extra edge. Fuel with low oil is great for speed but longevity will diminish rapidly. All out competition racers expect to win races at the cost of racing engines.
If you want to run your sport XX46XX engine with a competition type low oil fuel in an effort to gain more performance, you may in fact ruin it. If you want a high performance engine, buy a Nelson, Jett, Rossi, MVVS or a couple others. Most these engines makers offer a sport style engine that is very high in performance. But keep in mind that even these high performance "sport" engines require a higher oil content that what competition fules usually have.
The overall answer is if you want to go faster, buy a faster engine, but you still need to properly feed it. No such sport recipies exist.
I have made fuel to compare the performance gain by cutting down the oil content. On a Super Tiger 75, my traditional 20% ringed engine oil blend at 15% nitro only turned 40 rpms less than a fuel with 17% oil. Is that a significant amount?- definatly not! however, the down side was that the lower oil fuel ran 38 degrees hotter at the maximum rpm. That's Significant!!!!
Q: What type of glow plug works best with xx% of fuel.
A: General rule of thumb:
High nitro fuels need a colder plug and,
Lower nitro fuels need a hotter plug.
4-strokes need 4-stroke plugs, they are very hot.
Heli's usually fly hot plugs.
I have compiled a list of some common plugs and catagorized it by heat range as specified by the manufacturer. e-mail me if you want a copy.
Fuelman
__________________
03-09-2002, 08:15 PM
#3
Rc Fuel Faq
Ricec5,
Your absolutly right, however, there are always exceptions to every general rule.
Many heli engines recommend a hot plug to keep the fire lit during idle and midrange and to help keep midrange transition as crisp and clean as possible. This is usually compensated for by richening up the needles so that detonation does not occur. I know some heli fliers that add an extra head shim to help compensate as well.
Can heli engines be run on colder plugs? sure but some of the charactistics of how the engine runs may change and retuning will definetly need to be done.
Fuelman
Your absolutly right, however, there are always exceptions to every general rule.
Many heli engines recommend a hot plug to keep the fire lit during idle and midrange and to help keep midrange transition as crisp and clean as possible. This is usually compensated for by richening up the needles so that detonation does not occur. I know some heli fliers that add an extra head shim to help compensate as well.
Can heli engines be run on colder plugs? sure but some of the charactistics of how the engine runs may change and retuning will definetly need to be done.
Fuelman
03-16-2002, 12:11 PM
#4
More Q&A
I am printing a list of some of the questions and my private replies that people have asked through e-mail to me.
Most of the questions were buggy/car engine specific but have relavance to all glow engines.
Q:Why use more nitro or why not...
A: Nitro is a fuel that caries its own oxygen, that is where the power comes from. You need to richen up the high speed needle if you run higher nitro contents since the fuel caries its own oxygen, you can burn more fuel and create more heat. The proper nitro content for an engine largely depends on the compresson ratio and to a lesser extent the needle settings. If your engine is not compressed for example 30% nitro, you can still run it and realize a gain in performance if you can control the detonation and excess heat. Richening up the needle to keep the heat inside its range will help you control detonation, but you may actually be chasing needle settings and be back to the performance of a lower nitro fuel. If you are going to run more nitro than what is recommended by the manufacturer, start off with the next higher nitro blend and see if it can be tuned to your engine. If you absolutly have to run more, and your engine is running unacceptably hot and/or detonating (frying egg sound) then add a head shim to lower your compression ratio.
Q: Effects of nitro content...(question from a buggy driver)
A: More nitro in the fuel means more heat produced which means more potential power. Since you are actually packing more fuel into the combustion chamber with more nitro (hence the richer needle settings) you are doing a couple things: creating more heat and burning more fuel which equates to shorter run times on a given tank of fuel. Higher nitro fuels may need a different glow plug, the higher the nitro the cooler the plug needs to be so the fuel is not pre-detonating before the piston is at top dead center causing detonation and ruining rods and melting down pistons. You may or may not need a different plug depending on how you tune the engine and how the engine is compressed.
Q: Effects of oil content... (question from a buggy driver)
A: Oil is Life Insurance for your engines! Although most car & buggy engines run just fine on very low oil (usually under 14%), more oil will never hurt anything. Oil does two things for your engine- it lubricates and it carries away heat. When oil content is reduced to enhance top end power (less oil means more burnable components), proper break in and needle settings become critical. When an engine is leaned out for performance, you are actually supplying your engine with less oil and creating more heat. Thats fine untill you get to a certain lean point where the heat is too high and their isn't enough oil to keep the engine from rapidly accelerating its wear or coming apart. Not enough oil between moving parts (primarly the piston and sleeve and rod journal) will cause the metal parts to actually be scrubbing against each other. Don't run it too lean and run at least what the manufacturer recommends for oil contents, even more for break in is fine. I have found that a fuel containing significantly more oil than the average buggy fuel runs just fine in buggy engines and they last a long time. Competition drivers will probably want the low oil high performance fuels but for the average sport driver the higher oil contents run great.
(This was from a buggy guy, but it applies to all ABC Type engines)
Q: Engine temp...
A: Engine operating temprature is dictated by design type. Car/buggy engines are of ABC or ABC type construction. this means that there is an Aluminum piston riding in a Brass sleeve that is Chrome plated. ABC engines are of an interference fit, the cylinder sleeve is actually tapered so the piston pinches the further up the sleeve it travels. With ABC engines, you get excellent compression as long as you can maintain the tight tolerences. These engines are designed so the top of the cylinder sleeve expands faster than the piston itself so the fit is optimal at operating tempretures. The engine needs to come up to tempreture real fast in order for the sleeve to properly expand to acheive optimal fit, otherwise the piston will be wearing real hard against the sleeve and the precision fit will be lost and the engine will lose most of its compression and performance. The sleeve will start expanding to design peramiters at around 230 degrees F. Anything less the piston will be scrubbing hard against the sleeve and rapidly wear the piston and sleeve which will loose that nice tight compression. When running your engine, keep the engine at least 230 deg. Your engine will last much longer and give more performance.
Q: Needle settings...(from a buggy driver, applies to all ABC type engines)
A: When breaking in an engine, put the needles where the manufacturer recommends and use the nitro & oil content they recommend for break in. When needling an engine, never let your ABC engine run blurbbry rich- that does not allow the piston and sleeve to heat up. As far as needle settings go, when running at high speed if the engine sags or looses power you are too lean, you must richen it up some. On the other side if your engine does not clean out and is stumbling at wide open, lean it a touch. Off idle response after break-in should be crisp and even. If your are getting a slow spitting or stumbling type of acceleration you are too rich on the idle mixture, lean the idle mixture an 1/8 turn until it cleans out. If your getting a sagging response off idle where the engine sounds like its starving for fuel it is too lean, richen idle mixture about an 1/8 turn. It is important to make mixture adjustments a little at a time, especially on the idle side. Never try adjusting a carburator based on how it runs when its not to operating tempreture- you'll be chasing the needle settings all over the place. Weather changes have significant affects on the needles, changes in weather may require you to adjust the needles.
Q: Tuned pipe info...
A: Tuned pipes allow the exhaust pressure waves to actually suck more fuel mixture into the combustion chamber and scavange more exhaust out while the exhaust port is still open. Tuning the length of the pipe and having the correct volume are essential for maximum efficiency. Numerous variables have to be taken into consideration such as: engine, gear ratios, torque band
your looking for (high end, low end or mid range), type of racing or runing (or type of flying). It is sometimes best to follow the engine manufacturers and pipe manufacturers instructions for tunig a pipe to your application.
Q: Why coil the pressure line on car & buggy engines...
A: I can not think of one valid reason why. Some prominate "Car" expert probably did it just to see if everybody else would follow. Or it could have probably been cooked up by the fuel tubing manufacturers. Just my opinion. (a little humor here folks)
Q: What about break in for my car engine...
A: NEVER NEVER run your engine so rich it hardly runs. This will do more damage to ANY ABC engines piston to sleeve fit than you want. It is critically important to get that engine up to at least 230 degrees as fast as you can to minimize that wear, even on initial start-up. Do not let the engine sit and idle for the first tank. Start it up, bring the speed up (not necessarly wide open), get the temp up and get the needle to where it will hold that 230 degrees. Run your engine in short runs of 2 or 3 minutes for the first couple of tanks with letting the engine cool down completly between runs, this heat cycles the engine and makes for a longer lasting engine. You should run at least the amount of oil in your fuel that the manufacturer recommends for the first quart or so, you can even run more oil than what is recommended for break in, it will only allow your engine to last longer. Before starting your engine for the first time, take out the plug and put in 2-3 drops of oil and do the same thing down the carburator- this gives your engine some additional initial lubrication for its first startup. Always run a fuel filter and an air filter.
Keep sending me the questions to my e-mail. I will answer them the best I can and in time post them to this forum.
Fuelman
Most of the questions were buggy/car engine specific but have relavance to all glow engines.
Q:Why use more nitro or why not...
A: Nitro is a fuel that caries its own oxygen, that is where the power comes from. You need to richen up the high speed needle if you run higher nitro contents since the fuel caries its own oxygen, you can burn more fuel and create more heat. The proper nitro content for an engine largely depends on the compresson ratio and to a lesser extent the needle settings. If your engine is not compressed for example 30% nitro, you can still run it and realize a gain in performance if you can control the detonation and excess heat. Richening up the needle to keep the heat inside its range will help you control detonation, but you may actually be chasing needle settings and be back to the performance of a lower nitro fuel. If you are going to run more nitro than what is recommended by the manufacturer, start off with the next higher nitro blend and see if it can be tuned to your engine. If you absolutly have to run more, and your engine is running unacceptably hot and/or detonating (frying egg sound) then add a head shim to lower your compression ratio.
Q: Effects of nitro content...(question from a buggy driver)
A: More nitro in the fuel means more heat produced which means more potential power. Since you are actually packing more fuel into the combustion chamber with more nitro (hence the richer needle settings) you are doing a couple things: creating more heat and burning more fuel which equates to shorter run times on a given tank of fuel. Higher nitro fuels may need a different glow plug, the higher the nitro the cooler the plug needs to be so the fuel is not pre-detonating before the piston is at top dead center causing detonation and ruining rods and melting down pistons. You may or may not need a different plug depending on how you tune the engine and how the engine is compressed.
Q: Effects of oil content... (question from a buggy driver)
A: Oil is Life Insurance for your engines! Although most car & buggy engines run just fine on very low oil (usually under 14%), more oil will never hurt anything. Oil does two things for your engine- it lubricates and it carries away heat. When oil content is reduced to enhance top end power (less oil means more burnable components), proper break in and needle settings become critical. When an engine is leaned out for performance, you are actually supplying your engine with less oil and creating more heat. Thats fine untill you get to a certain lean point where the heat is too high and their isn't enough oil to keep the engine from rapidly accelerating its wear or coming apart. Not enough oil between moving parts (primarly the piston and sleeve and rod journal) will cause the metal parts to actually be scrubbing against each other. Don't run it too lean and run at least what the manufacturer recommends for oil contents, even more for break in is fine. I have found that a fuel containing significantly more oil than the average buggy fuel runs just fine in buggy engines and they last a long time. Competition drivers will probably want the low oil high performance fuels but for the average sport driver the higher oil contents run great.
(This was from a buggy guy, but it applies to all ABC Type engines)
Q: Engine temp...
A: Engine operating temprature is dictated by design type. Car/buggy engines are of ABC or ABC type construction. this means that there is an Aluminum piston riding in a Brass sleeve that is Chrome plated. ABC engines are of an interference fit, the cylinder sleeve is actually tapered so the piston pinches the further up the sleeve it travels. With ABC engines, you get excellent compression as long as you can maintain the tight tolerences. These engines are designed so the top of the cylinder sleeve expands faster than the piston itself so the fit is optimal at operating tempretures. The engine needs to come up to tempreture real fast in order for the sleeve to properly expand to acheive optimal fit, otherwise the piston will be wearing real hard against the sleeve and the precision fit will be lost and the engine will lose most of its compression and performance. The sleeve will start expanding to design peramiters at around 230 degrees F. Anything less the piston will be scrubbing hard against the sleeve and rapidly wear the piston and sleeve which will loose that nice tight compression. When running your engine, keep the engine at least 230 deg. Your engine will last much longer and give more performance.
Q: Needle settings...(from a buggy driver, applies to all ABC type engines)
A: When breaking in an engine, put the needles where the manufacturer recommends and use the nitro & oil content they recommend for break in. When needling an engine, never let your ABC engine run blurbbry rich- that does not allow the piston and sleeve to heat up. As far as needle settings go, when running at high speed if the engine sags or looses power you are too lean, you must richen it up some. On the other side if your engine does not clean out and is stumbling at wide open, lean it a touch. Off idle response after break-in should be crisp and even. If your are getting a slow spitting or stumbling type of acceleration you are too rich on the idle mixture, lean the idle mixture an 1/8 turn until it cleans out. If your getting a sagging response off idle where the engine sounds like its starving for fuel it is too lean, richen idle mixture about an 1/8 turn. It is important to make mixture adjustments a little at a time, especially on the idle side. Never try adjusting a carburator based on how it runs when its not to operating tempreture- you'll be chasing the needle settings all over the place. Weather changes have significant affects on the needles, changes in weather may require you to adjust the needles.
Q: Tuned pipe info...
A: Tuned pipes allow the exhaust pressure waves to actually suck more fuel mixture into the combustion chamber and scavange more exhaust out while the exhaust port is still open. Tuning the length of the pipe and having the correct volume are essential for maximum efficiency. Numerous variables have to be taken into consideration such as: engine, gear ratios, torque band
your looking for (high end, low end or mid range), type of racing or runing (or type of flying). It is sometimes best to follow the engine manufacturers and pipe manufacturers instructions for tunig a pipe to your application.
Q: Why coil the pressure line on car & buggy engines...
A: I can not think of one valid reason why. Some prominate "Car" expert probably did it just to see if everybody else would follow. Or it could have probably been cooked up by the fuel tubing manufacturers. Just my opinion. (a little humor here folks)
Q: What about break in for my car engine...
A: NEVER NEVER run your engine so rich it hardly runs. This will do more damage to ANY ABC engines piston to sleeve fit than you want. It is critically important to get that engine up to at least 230 degrees as fast as you can to minimize that wear, even on initial start-up. Do not let the engine sit and idle for the first tank. Start it up, bring the speed up (not necessarly wide open), get the temp up and get the needle to where it will hold that 230 degrees. Run your engine in short runs of 2 or 3 minutes for the first couple of tanks with letting the engine cool down completly between runs, this heat cycles the engine and makes for a longer lasting engine. You should run at least the amount of oil in your fuel that the manufacturer recommends for the first quart or so, you can even run more oil than what is recommended for break in, it will only allow your engine to last longer. Before starting your engine for the first time, take out the plug and put in 2-3 drops of oil and do the same thing down the carburator- this gives your engine some additional initial lubrication for its first startup. Always run a fuel filter and an air filter.
Keep sending me the questions to my e-mail. I will answer them the best I can and in time post them to this forum.
Fuelman
04-09-2002, 06:40 PM
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Rc Fuel Faq
Fuel Facts from Don Nix, good general reference from a former fuel manufacturer.
http://home.tampabay.rr.com/tbrhodes/fuel
http://home.tampabay.rr.com/tbrhodes/fuel
04-09-2002, 08:54 PM
#6
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Don K Fuel Facts
I take exception to Don Nixes fuel facts when he states that 4 strokes need less oil than 2 strokes.
Here is my reason why I feel that 4 strokes need as much oil as a 2 stroke.
4 strokes actually run hotter in my opinion than 2 strokes because they do not have the cooling effect of the fuel vaporizing in the crankcase (latent heat of vaporization) before it is burned.
4 stroke engine bearings are not lubricated directly as they are in a 2 stroke (induction of fuel through a hollow crankshaft). 4 strokes rely on blowby past the piston ring for lubrication.
My hypothesis that 4 strokes run hotter than 2 strokes is supported by emprical data: 4 stroke heli engines all overheat in hot weather and 2 stroke heli engines hold up fine in helis regardless of outside temp. This is why 4 stroke heli engines aren't popular though a 4 stroke motor would be better suited for a heli than a 2 stroke in maintaining constant rotor rpm over various loads imposed by the rotors system.
Here is my reason why I feel that 4 strokes need as much oil as a 2 stroke.
4 strokes actually run hotter in my opinion than 2 strokes because they do not have the cooling effect of the fuel vaporizing in the crankcase (latent heat of vaporization) before it is burned.
4 stroke engine bearings are not lubricated directly as they are in a 2 stroke (induction of fuel through a hollow crankshaft). 4 strokes rely on blowby past the piston ring for lubrication.
My hypothesis that 4 strokes run hotter than 2 strokes is supported by emprical data: 4 stroke heli engines all overheat in hot weather and 2 stroke heli engines hold up fine in helis regardless of outside temp. This is why 4 stroke heli engines aren't popular though a 4 stroke motor would be better suited for a heli than a 2 stroke in maintaining constant rotor rpm over various loads imposed by the rotors system.
04-10-2002, 10:33 PM
#7
Rc Fuel Faq
Right on Homebrewer,
I do not subscribe to Don Nix's rationalle either.
I have run various 4-strokes with various oil quantities and blends and most of the popular fuels manufacturered out there.
What I've noticed is that lower oil fuels 16-17% do run and do run just fine. They actually can run a few rpms more (generally well under 100) than 20% oil fuels of the same nitro content. The downside is decreased longevity of the enigne, much hotter running and less steady needle settings.
A 20% oil fuel is just as easy to run as a low oil fuel. 99% of fliers out there will never notice anything but a little better smoke trail, a little friendlier engine to run and adjust and one that runs much cooler, especially in tightly cowled applications.
Here's the best part- 20% oil fuel does not cost any more than low oil fuel (at least with a few manufacturers) even though it is more expensive to make.
Good philosophy Homebrewer.
Fuelman
I do not subscribe to Don Nix's rationalle either.
I have run various 4-strokes with various oil quantities and blends and most of the popular fuels manufacturered out there.
What I've noticed is that lower oil fuels 16-17% do run and do run just fine. They actually can run a few rpms more (generally well under 100) than 20% oil fuels of the same nitro content. The downside is decreased longevity of the enigne, much hotter running and less steady needle settings.
A 20% oil fuel is just as easy to run as a low oil fuel. 99% of fliers out there will never notice anything but a little better smoke trail, a little friendlier engine to run and adjust and one that runs much cooler, especially in tightly cowled applications.
Here's the best part- 20% oil fuel does not cost any more than low oil fuel (at least with a few manufacturers) even though it is more expensive to make.
Good philosophy Homebrewer.
Fuelman
04-27-2002, 10:03 PM
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Re: More Q&A
Originally posted by Fuelman
Q: Why coil the pressure line on car & buggy engines...
A: I can not think of one valid reason why. Some prominate "Car" expert probably did it just to see if everybody else would follow. Or it could have probably been cooked up by the fuel tubing manufacturers. Just my opinion.
Fuelman
Q: Why coil the pressure line on car & buggy engines...
A: I can not think of one valid reason why. Some prominate "Car" expert probably did it just to see if everybody else would follow. Or it could have probably been cooked up by the fuel tubing manufacturers. Just my opinion.
Fuelman
04-28-2002, 04:38 AM
#11
Rc Fuel Faq
Gubbs3,
I knew that being a bit of a "wise guy" in that part of the Fuel FAQ's would generate some feedback.
Good reasoning Gubbs3. I was very interested in learning more about the idea of coiling the pressure line but could not find anything in hard data in print. To say the least, I was very skeptical about exactly what you mention- reducing pressure to the tank at high rpm's. So I devised a test.
I took an my off the shelf buggy with a very popular 15 engine in it with a tuned pipe and coiled up a long piece of fuel tubing going from pipe to tank. Result- No difference in running. Not convinced, I then made a second pressure tap in the pipe and hooked up the second tap to a calibrated pressure guage (0 to 5 psi). Running the engine at wide open with short and long pieces of fuel tubing, coiled and straight, I did not see a difference in line pressure. The only time I saw reduced line pressure was when I purposely restricted it by pinching.
Now, is my simple test flawed? Sure it is, i only used one type of engine and a stock tuned pipe on an off the shelf RTR buggy. Is that indicitave to all car/buggy applications?- no, however i feel it is an adequate representation to the average sport car/buggy driver that runs off the shelf equipment. Will a high dollar racing engine and pipe act differently?- maybe, however I'm not going to purchase one to find out.
Fuelman
I knew that being a bit of a "wise guy" in that part of the Fuel FAQ's would generate some feedback.
Good reasoning Gubbs3. I was very interested in learning more about the idea of coiling the pressure line but could not find anything in hard data in print. To say the least, I was very skeptical about exactly what you mention- reducing pressure to the tank at high rpm's. So I devised a test.
I took an my off the shelf buggy with a very popular 15 engine in it with a tuned pipe and coiled up a long piece of fuel tubing going from pipe to tank. Result- No difference in running. Not convinced, I then made a second pressure tap in the pipe and hooked up the second tap to a calibrated pressure guage (0 to 5 psi). Running the engine at wide open with short and long pieces of fuel tubing, coiled and straight, I did not see a difference in line pressure. The only time I saw reduced line pressure was when I purposely restricted it by pinching.
Now, is my simple test flawed? Sure it is, i only used one type of engine and a stock tuned pipe on an off the shelf RTR buggy. Is that indicitave to all car/buggy applications?- no, however i feel it is an adequate representation to the average sport car/buggy driver that runs off the shelf equipment. Will a high dollar racing engine and pipe act differently?- maybe, however I'm not going to purchase one to find out.
Fuelman
06-04-2002, 03:51 PM
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H2o.
FuelMan,
Excellent Faq about fuels. I'm adding it to my "favorites" list.
I have a question about the very first one you posted to do with water in our fuel. It sounded like once fuel is contaminated with water (or absorbed) into the fuel there is little you can do. It seems to me that it simply falls to the bottom of the container and you can just pour off the good and leave the water behind. Is there more water in the fuel that I can't see??
I pour my fuel into a one of those Dave Brown 1 gal cans and the little beads of water become very visible after a while so I just dispose of the last 1/4 inch or so before I refill. Is this not a good method?? Thanks for your effort we all appreciate it
Excellent Faq about fuels. I'm adding it to my "favorites" list.
I have a question about the very first one you posted to do with water in our fuel. It sounded like once fuel is contaminated with water (or absorbed) into the fuel there is little you can do. It seems to me that it simply falls to the bottom of the container and you can just pour off the good and leave the water behind. Is there more water in the fuel that I can't see??
I pour my fuel into a one of those Dave Brown 1 gal cans and the little beads of water become very visible after a while so I just dispose of the last 1/4 inch or so before I refill. Is this not a good method?? Thanks for your effort we all appreciate it
06-04-2002, 08:53 PM
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Freezing
Heard a similar method, namely cooling of your jug in the freezer to below 0°C (32°F for the rest of you non metric) and pouring of the unfrozen alcohol and oil, leaving the ice behind. And the big question is ...
06-06-2002, 03:57 PM
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Rc Fuel Faq
What fuel do you recomend for the Weston 50V1 Engine.
I cant not import any fuel and the hobby shop here dont want to bring any special order.
The only fuel available here were I live Panama Central America is:
Byron Castor/Synthetic Blend 10% Nitro 16% oil
Byron Castor/Synthetic Blend 15% Nitro 16% oil
Wilcat 100% Synthetic 15% Nitro 18% oil
I think the Weston 50 Engine dont like high Nitro.
I actually using Byron 10% Nitro 16% oil in my regular airplanes Webras 50GT Aero Speed with 11 x 5 APC props but they dont get more than 14.5K RPM and they are doing good and there is not problem with bearings. BUT what about doing more than 20K RPM on the West 50V1 with this fuel???
THX,
Isaac
I cant not import any fuel and the hobby shop here dont want to bring any special order.
The only fuel available here were I live Panama Central America is:
Byron Castor/Synthetic Blend 10% Nitro 16% oil
Byron Castor/Synthetic Blend 15% Nitro 16% oil
Wilcat 100% Synthetic 15% Nitro 18% oil
I think the Weston 50 Engine dont like high Nitro.
I actually using Byron 10% Nitro 16% oil in my regular airplanes Webras 50GT Aero Speed with 11 x 5 APC props but they dont get more than 14.5K RPM and they are doing good and there is not problem with bearings. BUT what about doing more than 20K RPM on the West 50V1 with this fuel???
THX,
Isaac
06-07-2002, 09:05 PM
#15
Rc Fuel Faq
Ninefingers:
You live in a very humid area, it is very hard not to get any water alcohol comtamination.
Water and methanol have an attraction to one another (so to speak). To the best of my knowledge, once methanol and water are combined, it is rather difficult to separate with common means. I'll have to talk to my chemist to get his input. He has used molecular seives to extract the water from methanol, however that does not mean that other methods do not exist.
As far as pouring the fuel off the water, I'm afraid that once that amount of separation occurs (oil separates from the combustables), you may be beyond the point of saving any remaining fuel in that container. Small amounts of moisture in fuel will not separate out and fall to the bottom.
I hope that answers your question.
DerFly:
Old moonshiners trick, freeze the hard cider and pour off the apple jack! You can try it, and post your results, I'd love to hear the results.
Please keep us posted.
IssacF:
Not familiar with that engine or its oil & nitro requirements.
please send me a web site link where I can find more info.
Fuelman
You live in a very humid area, it is very hard not to get any water alcohol comtamination.
Water and methanol have an attraction to one another (so to speak). To the best of my knowledge, once methanol and water are combined, it is rather difficult to separate with common means. I'll have to talk to my chemist to get his input. He has used molecular seives to extract the water from methanol, however that does not mean that other methods do not exist.
As far as pouring the fuel off the water, I'm afraid that once that amount of separation occurs (oil separates from the combustables), you may be beyond the point of saving any remaining fuel in that container. Small amounts of moisture in fuel will not separate out and fall to the bottom.
I hope that answers your question.
DerFly:
Old moonshiners trick, freeze the hard cider and pour off the apple jack! You can try it, and post your results, I'd love to hear the results.
Please keep us posted.
IssacF:
Not familiar with that engine or its oil & nitro requirements.
please send me a web site link where I can find more info.
Fuelman
06-07-2002, 10:08 PM
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IssacF: IssacF:
Not familiar with that engine or its oil & nitro requirements.
please send me a web site link where I can find more info.
Not familiar with that engine or its oil & nitro requirements.
please send me a web site link where I can find more info.
This engine is a Webra 50 GT AeroSpeed modified with Weston UK spec to get aound 22,000 RPM with a Weston Pipe. They recomend to use a Synthetic fuel with 20% oil but as my last post say I can not get that fuel here in Panama.
I am actually using Byron 10%Nitro 16%oil Castor/Synthetic fuel in my regular airplanes with Webras 50GT Aero Speed with 11 x 5 APC props BUT they dont get more than 14,500 RPM and they are doing good and there is not problem with bearings. BUT what about doing more than 20K RPM on the West 50V1 with this fuel???
Maybe I can buy here Wilcat 100% Synthetic 15% Nitro 18% oil
and add oil.
Now what oil I have to add and how many ounces to the gallon to be safe.
I also has write to Weston with this question but they have not answer me
Here is the address: http://www.westonuk.co.uk/west.html
THX,
Isaac
06-08-2002, 01:00 AM
#17
Rc Fuel Faq
Isaac:
I e-mailed you privately with some thoughts.
In a nutshell for everybody else; In the smaller Webra's I prefer low nitro and high winding props. Webra engines tend to be higher in compression to many other offerings and are well suited to low or no nitro fuel. Most Webra's are big bore and short stroked which means they like to wind up rather than be lugged down with a larger diameter prop. For instance on a Webra 50, I liked 10x6 props and a 5% nitro/ 20% oil fuel with at least some castor in it. I can't recall or find my spec sheets, but that combo turned considerably more than 14.5K, with incredible throttle response and all around friendly running habits.
Fuelman
I e-mailed you privately with some thoughts.
In a nutshell for everybody else; In the smaller Webra's I prefer low nitro and high winding props. Webra engines tend to be higher in compression to many other offerings and are well suited to low or no nitro fuel. Most Webra's are big bore and short stroked which means they like to wind up rather than be lugged down with a larger diameter prop. For instance on a Webra 50, I liked 10x6 props and a 5% nitro/ 20% oil fuel with at least some castor in it. I can't recall or find my spec sheets, but that combo turned considerably more than 14.5K, with incredible throttle response and all around friendly running habits.
Fuelman
06-16-2002, 02:30 AM
#19
Rc Fuel Faq
Jack Jet,
I assume you are refering to Mobil Jet II and all the Exxon and Shell variations?
I have experimented around some with Jet Turbine oils as a glow fuel lubricant. Although it does work in low percentages of oil (around 5% give or take), it does have some very serious drawbacks. First of all, turbine oil is a carcinogen and what are the burnt byproducts of those carcinogens doing?, I don't know. Second, it will turn the fuel mixture dark to black in very short time. That tells me that some very interesting chemical reactions are going on that are outside of our control. Too many unknowns for me to suggest anybody using it.
We already know its a carcinogen and thats bad enough.
Hope that helps you out.
I assume you are refering to Mobil Jet II and all the Exxon and Shell variations?
I have experimented around some with Jet Turbine oils as a glow fuel lubricant. Although it does work in low percentages of oil (around 5% give or take), it does have some very serious drawbacks. First of all, turbine oil is a carcinogen and what are the burnt byproducts of those carcinogens doing?, I don't know. Second, it will turn the fuel mixture dark to black in very short time. That tells me that some very interesting chemical reactions are going on that are outside of our control. Too many unknowns for me to suggest anybody using it.
We already know its a carcinogen and thats bad enough.
Hope that helps you out.
06-16-2002, 02:51 AM
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Turbine oil ?
Fuelman,
you are 100% right about some bad stuff in turbine oil (Exxon2380)-when it burns as when I run my Ram 500 turbine and you breathe even just a little of the exhaust gas-it gives a me a major headache-and it lasts all day too-I just put only 1oz. of it in my glow fuel-so maybe it wont be as bad..............anyway thanks for your reply-you are doing the modeling world a great service.
Jackjet
you are 100% right about some bad stuff in turbine oil (Exxon2380)-when it burns as when I run my Ram 500 turbine and you breathe even just a little of the exhaust gas-it gives a me a major headache-and it lasts all day too-I just put only 1oz. of it in my glow fuel-so maybe it wont be as bad..............anyway thanks for your reply-you are doing the modeling world a great service.
Jackjet
07-01-2002, 01:18 AM
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Rc Fuel Faq
Hello Fuel Man, how you doing?
Just to be sure I understand your last recomendation.
If I use a Castor/Synthetic Blend fuel like Morgan Omega Fuel I have to add Klotz 100% Synthetic Oil (Original Techiplate KL-200)
If I use a 100 Synthetic fuel like Morgan Cool Power fuel I have to add Klotz Castor/Synthetic oil (Super Techniplate KL-100)
Is this is correct????
Thank you for you help and time.
Isaac Fajgenbaum
Just to be sure I understand your last recomendation.
If I use a Castor/Synthetic Blend fuel like Morgan Omega Fuel I have to add Klotz 100% Synthetic Oil (Original Techiplate KL-200)
If I use a 100 Synthetic fuel like Morgan Cool Power fuel I have to add Klotz Castor/Synthetic oil (Super Techniplate KL-100)
Is this is correct????
Thank you for you help and time.
Isaac Fajgenbaum
08-26-2002, 02:39 PM
#22
Rc Fuel Faq
Separating contaminating water from glow fuel
Water and methanol are completely miscible, meaning that one dissolves the other in any proportion. Freezing the mixture, letting it settle, etc., have no effectiveness at all. The oil and nitro may separate during such efforts, but the water and methanol stay together. There is no way to remove the water from contaminated fuel since distillation would destroy the nitromethane, and the presence of oil in the mix would make it a difficult, greasy process. With oil and nitro, the molecular sieve would be similarly ineffective.
If your fuel gets contaminated with water, the most cost- and time-effective approach is to throw it away and buy some more.
If your 55 gal drum of pure methanol gets contaminated, maybe distillation offers hope in restoration. No moonshiner that I know would allow you to use his still, though, since methanol is very poisonous, and his customer base will be reduced if his product (ethanol) is contaminated with methanol.
BTW--since gasoline and water do not have a significant affinity for each other, settling and freezing methods do work.
Water and methanol are completely miscible, meaning that one dissolves the other in any proportion. Freezing the mixture, letting it settle, etc., have no effectiveness at all. The oil and nitro may separate during such efforts, but the water and methanol stay together. There is no way to remove the water from contaminated fuel since distillation would destroy the nitromethane, and the presence of oil in the mix would make it a difficult, greasy process. With oil and nitro, the molecular sieve would be similarly ineffective.
If your fuel gets contaminated with water, the most cost- and time-effective approach is to throw it away and buy some more.
If your 55 gal drum of pure methanol gets contaminated, maybe distillation offers hope in restoration. No moonshiner that I know would allow you to use his still, though, since methanol is very poisonous, and his customer base will be reduced if his product (ethanol) is contaminated with methanol.
BTW--since gasoline and water do not have a significant affinity for each other, settling and freezing methods do work.
08-28-2002, 03:01 AM
#23
Rc Fuel Faq
W4KV:
Interesting post! Thank you.
The key to keeping water out of the methanol or glow fuel is to prevent it in the first place. As discussed in much earlier posts, keeping glow fuel water contamination to a minimum mostly resides with the end user's field box. Having it tightly caped and preventing ambient air from entering is the best measure of defense. Obviously, not much can be done while refuling or defueling a tank, but that is only a few minutes out of the entire time you own the bottle of fuel. The remaining time, it should be tightly caped and I would recommend you have a refueling system that can be caped off as well.
Remember to minimize the sunlight on the fuel bottle as well.
As far as manufacturing goes, I seriously doubt that any manufacturer of glow fuel is careless with methanol storage.
Fuelman
Interesting post! Thank you.
The key to keeping water out of the methanol or glow fuel is to prevent it in the first place. As discussed in much earlier posts, keeping glow fuel water contamination to a minimum mostly resides with the end user's field box. Having it tightly caped and preventing ambient air from entering is the best measure of defense. Obviously, not much can be done while refuling or defueling a tank, but that is only a few minutes out of the entire time you own the bottle of fuel. The remaining time, it should be tightly caped and I would recommend you have a refueling system that can be caped off as well.
Remember to minimize the sunlight on the fuel bottle as well.
As far as manufacturing goes, I seriously doubt that any manufacturer of glow fuel is careless with methanol storage.
Fuelman
08-28-2002, 05:47 AM
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Just For Info
I have been using turbine oil in my fuel for about ten years now, in about a 2% concentration (2.75 oz per gall) because it greatly extends the life of the bearings. It will turn black relatively quickly, and even faster when exposed to sun light. I try to use the fuel within seven days of mixing. Any and all exposed brass tubing will also turn black. If I wind up storing a gallon over winter, and use it in the spring, I find that the black fuel runs just fine. I also run low oil fuels in all of my engines around 14%, with a 50/50 Castor synthetic blend, but I never run my engines lean. I also make a habit of running larger than normal props, and never running my engines over 10,000 revs. I have never had to replace a connecting rod because of a warn out big end. Since I quit using OS engines about nine years ago, I have had not to replace a single ball bearing in my Super Tigres, or MVVS engines. I do find that the Turbine oil seams to increase the flame speed, and hence, carbonize the Castor oil in the combustion chamber. But because of the low oil content of the fuel, the engines do not detonate.
For what ever this info is worth, I hope it helps to answer some questions. I am not trying to start any arguments or not trying to disprove anything. I am just simply stating what works for me.
Thank You for Listening.
Otto
For what ever this info is worth, I hope it helps to answer some questions. I am not trying to start any arguments or not trying to disprove anything. I am just simply stating what works for me.
Thank You for Listening.
Otto
08-30-2002, 12:33 AM
#25
Rc Fuel Faq
Fuelman said:
As far as manufacturing goes, I seriously doubt that any manufacturer of glow fuel is careless with methanol storage.
I agree. But I read some of these posts, and I get the impression that there are guys who buy methanol by the drum so that they can formulate their own glow fuel. Unless they do something about the air at the top, they could experience a problem if it sits around for a month or so and is opened very many times. Of course, if one makes a batch of 70 gallons or so at a time, no problema!
As far as manufacturing goes, I seriously doubt that any manufacturer of glow fuel is careless with methanol storage.
I agree. But I read some of these posts, and I get the impression that there are guys who buy methanol by the drum so that they can formulate their own glow fuel. Unless they do something about the air at the top, they could experience a problem if it sits around for a month or so and is opened very many times. Of course, if one makes a batch of 70 gallons or so at a time, no problema!