How do you know you engine is running perfect?
 

How do you know you engine is running perfect? 1. Like how many seconds should your engine run when you pinch the line? 2. And if it takes to long what do ya do? 3. Whats the best temp you should run it at and what nitro % do you use to get the longest life out of your engine?

Ok say if i got a new .21 engine and i am about to run it in using the new way. 4. Which needle do i need to lean? Just the high speed or both and how much?

Ok say if i got a engine running at 210 df, 5. Does this mean my engine is running good? 6. Or could my lsn be to leen and my hsn is a bit rich and is causing wear?

RE: How do you know you engine is running perfect?
 

O.K this can be a combination of things smoke level, performance, sound and heat your engine should have very little smoke at idle but plenty at high speed without bogging down, heat is personal preferance but i try to run my engines at about 95-100 degrees celsius for long life at maybe a slight but unnoticeable performance lag. If your car takes off like a rocket it's too lean at the bottom end or idling too high and riding the clutch if it idles inconsistently then settings are wrong if it suddenly rises then lowers and then rises etc. it's too lean if it chokes and splutters it's too rich. If it hits top end well then check temps, i use the spit test i try to get spit to not boil at all or at leat very slowly then it's about 95 c. for longest life use 0 nitro!!!! but for a .21 you can use up to 25 safely. If by the new way you mean the stephen bess method i would not reccomend it unless you have a picco engine, just take it slow run it rich and slowly increase performance over at the very least 6 tanks, but should be more.

Heat should be fairly stable across revs so if it overheats at low then i's too lean on the bottom if it overheats at high revs it's too lean on the top (Not completely sure about that last one, but fairly:D)

RE: How do you know you engine is running perfect?
 

thanks

RE: How do you know you engine is running perfect?
 

the piston wont stay silver forever, they will get a burnt color on the top so dont be alarmed if you see that, dont judge you tunning by pinching the fuel, that is very inaccurate because the time to kill the engine will vary depending on where you pinch the fuel line. the other guy covered tunning pretty good.

RE: How do you know you engine is running perfect?
 

Ok thanks for the tuning tips, as for running it in using Stephen Bess’s method, isn’t the main thing to do is get the engine up to operating temp, about 200 f, as quick as you can by preheating it or running it so it doesn’t cause premature wear? Just imagine the parts won’t be expanded and there will be allot of friction between the piston and cylinder causing wear. Then running it 1/4 a throttle for a couple tanks and shutting engine off until it cools with piston at bottom of cylinder, then running it 1/2 throttle for a couple tanks and so on... Makes sense to me.

Why don’t you recommend this way of breaking it in mk999? Allot of people said that this is the best way to get allot of power and a engine that will last a long time and they would never go back to the traditional method.

RE: How do you know you engine is running perfect?
 

JohnnyD. That is kinda the Stephen Bess Method. Check my posts earlier about it. And it IS IMO a Great way to break in a motor. ANd when you think about it, how a two stroke motor works, what is going on inside the engine, IT MAKES PERFECT SENSE!

RE: How do you know you engine is running perfect?
 

YEah it's basicly his method isnt it? I didnt have it on hand at the time i was writing it so i guessed it. lol
Thanks for the advice. My dad has got a 1/8 Swift coming from Hong Kong and should be here in a week or two so i decided to ask some questions and stuff.


Ok say i was running in .21 engine and i am about to run it in using the stephen bess's method. Which needle do i need to lean? Just the high speed or both and how much?

RE: How do you know you engine is running perfect?
 

YEah it's basicly his method isnt it? I didnt have it on hand at the time i was writing it so i guessed it. lol
Thanks for the advice. My dad has got a 1/8 Swift coming from Hong Kong and should be here in a week or two so i decided to ask some questions and stuff.


Ok say i was running in .21 engine and i am about to run it in using the stephen bess's method. Which needle do i need to lean? Just the high speed or both and how much?

RE: How do you know you engine is running perfect?
 

oh i see where i went wrong you need to run it with Wide Open Throttle!

RE: How do you know you engine is running perfect?
 

mk999 i take u perform ur test on the top of the heat sink

RE: How do you know you engine is running perfect?
 

I personally wouldn't use the stephen bess method because to me it sounds a bit harsh on a new engine and the other method I know works well and is used by a lot of people to great success. Think of it like this you are cutting a line into a piece of wood say, now the stephen bess method uses a chainsaw, quick, effective but there is a big chance you're going to cut too much much, now the tradional method does this with a nail file, takes longer, but just as effective and there is next to no chance you are going to take too much away. However this does seem to be down to personal preferance or wheteher you would like to try out a new method.

RE: How do you know you engine is running perfect?
 

yeah, i test on top of the heat sink, why? should i be testing somewhere else

RE: How do you know you engine is running perfect?
 

mk999 on my first engine i spent 3 hours running it in using the method on OFNA's site which is the old method. I was 4 stroking it but i didnt know, it was to rich, and after i finished running it in i thought it was hot ( didnt have a temp gun) and richend it up and the engine lost all compression after about 7 tanks of running it. Because of running it to cold...


Doesnt this tell you that the colder it is the more wear it is causing!! There for Stephen bass method is a better off way. The old way might work good for some but dout it is as good as Stepen Bass's method.

RE: How do you know you engine is running perfect?
 

OK, that is quite scary actually to think that running it in cold helps and then to find that out, are you sure you had no dirt get into the engine etc.

What do you mean 4-stroking?

RE: How do you know you engine is running perfect?
 

Yeah I know I couldn’t understand why it died. I am sure no dirt got in there. I thought it would last for ages running it that rich that’s why I had it rich. 4 stroking it is when the engine fires every 2nd time the piston is done its revelation. 2 Stroking it is, every time the piston comes up(smooth running). You know its 4 stroking it when it has a popping sound and there is a lot of smoke. Because it is firing every 2nd time it runs even cooler which causes more wear and uses more fuel.

Read this!!

By the way i didnt write this.

"This is from the engines page:

Idling an engine, letting it run slow, 1/4, 1/2 throttle is all incorrect. You want WOT after it warms up. YES WOT, even when it is brand new. This is in order to bring it up to the temp and fit the sleeve was designed to run at. Anything less and you are just leading your engine to an early death.

Yes, running at WOT slightly rich, but not 4 stroking rich is the proper way to do it. This explains the proper way and WHY it is the proper way. Here is some further explanation I wrote a while ago for newbie nitro guys that were still doing that incorrect idling method:

As for break-in, there is a whole lot of misunderstanding about this and basic engine operation. I have read and studied a lot of information on this and also by Dave Gierke who writes in RCCA and Model Airplane News (also by AirAge) about RC airplane and buggy engines and he's an expert. As well as Paris Racing, Stephen Bess, Clarance Lee, etc, in the research I have done over the last few years. It will take some time to convince yourself to bring a new engine to WOT but when you start to understand it and why it is correct, you will realize just how many people are completely breaking the engine totally incorrectly.


It’s important to learn the theory about how these engines run (2 stroke ABC, ABN, AAC), and how to break-in, especially because I see WAY TOO MANY people using the wrong procedure of idling many tanks of fuel through the engine. That is unnecessary and damaging which I will explain. Although we use the term “break-in”, by its word alone it is misleading because people wrongly assume it means to slowly and gradually bring an engine to tune by idling tanks of fuel but you will see why this is incorrect and unnecessarily wastes fuel too! Please be patient and read further to understand.

These engines use a sleeve around the piston to make the seal (piston doesn't have a ring) and it operates properly only with sufficient heat so that the sleeve can expand to its designed operating size and fit. All engines will be tight, especially when new, so on the initial runs, you want to have it get up to temp, so it can run how it is was designed to. By idling tanks and tanks through, overly rich and cool, the sleeve just wears MORE against the piston because it is not hot enough to expand to its operating size. And by doing that you are prematurely wearing out and ruining your engine. The piston/sleeve is designed to operate at running temps. Not doing this by running cool and rich on the bench leads to premature wear. By idling away tanks of fuel I GUARANTEE you are doing more harm than good. As long as the engine is warmed up first, you don’t have to drag out bringing it up to temp when it is brand new. It wont hurt or damage the working parts. These engines are very simple 2 stroke machines. They do not have extensive moving parts such as valves, cams, lifters, springs, etc. (like 4 strokers) so all this extra gentle, rich, cool operation is completely unnecessary (and worse it’s harmful). HOWEVER, the sleeve around the piston can be a delicate thing to maintain and it is not forgiving of improper treatment. And improper treatment of a piston and sleeve is running it at a temp it is not designed for. (either too cold or too hot, both are just as detrimental) Most often this is done by running it too rich which makes it too cold because the rich mixture doesn't generate enough combustion heat for proper sleeve expansion. Just as damaging can be an excessively lean run. If it is run overly lean for any length of time it will destroy the sleeve. (that is why fuels with castor oil as part of the lube mix are very good because they tolerate the too high heat of a very lean run and will help to save the sleeve if it is not run too lean for too long. but avoiding a lean run is essential when you know enough enough about engine tuning to avoid it)

Running a 2 stroke engine slow and rich makes it '4 stroke' which means it fires every other revolution, and that generates even less heat. It causes damage and wastes fuel as well! Using a fan is absolutely not necessary on it. Most important is to 'heat cycle' the engine at least 10 times to relieve the parts of manufacturing stresses. HEAT CYCLING REALLY IS WHAT BREAK IN IS ALL ABOUT. (I even think break-in should be called “Initial Heat Cycling” instead so that people understand what and why they are doing it.)

You run the engine in the car for 2 - 3 minutes at full throttle (yes, WOT, don’t baby it), ideally on a smooth paved level surface, after briefly warming up of course, and then shut down and repeat after the engine has fully cooled. Let it cool down completely. Heat cycling is the name of the game. You want it to come up to temp for a brief time, and cool down and repeat. After shutting down, adjust the flywheel so that the piston is at BDC (bottom dead center) so that it does not get stuck in the contracting/cooling sleeve, as can often happen. (If the piston should accidentally get stuck in the sleeve, preheat the cylinder to free the piston from the sleeve.)

During these initial runs YOU WANT the temps to be at least 200 F but not above 230-250 F. After break-in, running temps above 230F is fine. (in fact nitro engines perform best when run 250-300. below those temps they are less efficient and less powerful. However, going by the mixture is more important than trying to measure temp with heat guns, etc. which you may wind up doing inconsistently. The mixture setting on the High Speed Needle is critical in the first runs. It should be a rich and not lean setting. However it should not be so rich that it 4 strokes.

Also, to start a brand new engine it is very worthwhile to preheat the engine with a heat gun or hair dryer if it has a very tight piston/sleeve fit and you are having trouble turning it over to start it up. This will expand the sleeve some, and when you turn it over the piston will not excessively rub, or even get stuck in the sleeve (as sometimes can happen). Preheating really works well. You do want to run it on the rich side, but you want it to come up to temp also, just not more than 2-3 minutes in beginning runs, in order to keeps temps around 230F. Listen carefully to the exhaust noise or ‘note’, as you do not want it to be ‘4 stroking’. If it is, it needs to be leaned slowly until it runs 2 stroke. You can tell it is 4 stroking if it is very “boggy” and “hesitant” in acceleration and running. If it is making that “burbling” sound then it is 4 stroking which means it is running too rich and therefore too cold.

Everyone thinks they have to run it super cool and check to be sure temps are low. That's not what it is about. The reverse is true! Cool operation is damaging operation. Little, if any, break-in will occur unless it is heat cycled properly.

The manufactures can’t make a piston/sleeve turn over smoothly at room temp, because when the engine runs the sleeve will expand and there will be no seal at operating temp. See how that makes sense?!

So preheat it if necessary and don't run it cool, and heat cycle it, and you'll be good to go! After you have done this several times then you can gradually lean out the HSN to get best performance, but it should then be richened up just rich of peak to ensure it lasts long too. Running it at max peak rpm will lead to the shortest useful life of the piston and sleeve. If racing that is fine but if you are just playing you may want to run just a little richer than that peak setting. After the HSN is set then it is time to set the low and/or mid range needles and idling setting.

I see a lot of people idle the engine for a tank and then they let it cool off thinking that they are "heat cycling" it. However, because they are not running it up to WOT it is not generating enough heat to be of any use to a breakin/heat cycle. So, inadvertently by idling they are just letting the engine sleeve and piston wear away from the cold tight fit that they are allowing to happen when idling away on the bench. Research has shown that basically no breakin effect takes place AT ALL unless the engine is allowed to come up to operating temp for 2 minutes. So if you are idling away and then let it cool there is zero breakin/heat cycle benefit. But if you want to wear away the sleeve and piston fit then idling will definitely do it for you.

I hope this is helpful!!

P.S. If you want to hear it from him, read Dave Gierke’s article in the January 2002 issue of “RC Nitro” magazine! "


Convinced?!!!

Jon

RE: How do you know you engine is running perfect?
 

Not yet!!! surely if an engine gets hot the piston and cylinder expand both ways, see crudely drawn microsoftpaint pic;)

so keeping it cool reduces this expansion and therefore reduces wear

RE: How do you know you engine is running perfect?
 

Yes but the materials have different expansion rates.

BTW If you use the Stephen Bess (cowboy) method on a Hyper 21, don't come crying to me when your looking for a new crankshaft.

RE: How do you know you engine is running perfect?
 

Why did i have no compression after about 8 tanks of running it very rich after break in, using the old method? Doesnt this say somthing.

RE: How do you know you engine is running perfect?
 

Get it hot and get it hot quickly. The only way to do this without a heat gun is with lean mixture and high RPM. If you understand physics then you will know you are doing it right.

A cylinder will always increase in diameter when heated. Its all to do with Mass, Density and Volume. When a metal is heated it expands thus increasing its volume, Its mass cannot change so the density has to decrease, see formula below


Mass = density * volume
density = mass/volume
volume = mass/density

For the cylinder diameter to get smaller, the metal its made out of would have to be made more dense and thus be colder.

With the different metals in use, the rates of expanding metals are calculated to give the best fit when the engine is at normal opperating temp. I cant say no more so I repeat, Get it hot and get it hot quickly!!!!!!!

RE: How do you know you engine is running perfect?
 

Because you ran it very rich for too long.

RE: How do you know you engine is running perfect?
 

Yeah there for thats what happens when you are running it in using the old method. You may not notice it but it would probably wear the piston and sleeve more then stephen bess's mothed there for more compression after run in, therefore longer engine life.

RE: How do you know you engine is running perfect?
 

Maybe that's true but i ran my engine in a week ago it's had near enough to a gallon through it but i still can't turn the flywheel with my finger because of the pinch and compression and it is fully run in. I may be wrong but i'd say it meant that the 'traditional' method does a pretty good job[8D]

Edit:thanks for the explanation FaF was a little confused about that:D

RE: How do you know you engine is running perfect?
 

man, I read the best bit of info on the different break-in methods. I don't think I can find it though. The bottom line comes down to this:

1.) You have break-in methods for Pro racers that race an engine 1 day.

and

2.) You have break-in methods for folks that want to get the most life from their engines.

The WOT break-in and or idle X number of tanks through it, is for the folks in camp number 1. These guys want 100% power RIGHT NOW! They don't want to wait a gallon, they need power today. The sad part is that an engine broken in this manor will only last 2-3 gallons if even. ( I can bare witness to this because I followed the "idling" break-in for my hyper engine. It lasted 3 gallons.)

The heat cycle break in or the "Bess break-in" as it's been dubbed is for the folks that want the most life from their engines. The down side to this break-in method is that the tight seat between the piston and the sleeve can hold the engine back until it reaches about a gallon of fuel. After that gallon, it's fully broken in and will start to produce 100% power. The obvious advantage is that you'll be able to enjoy that $300 gem for 6-8 gallons if not more. You must, however, treat it well and supply it with well filtered air and fuel and you have to make sure it doesn't develop a leak in the case and "eat dirt". (My Top P5 has 1.5 gallons and it's really ripping, but turning the engine over by hand when it's cold is impossible. Hell, it's hard for the starterbox to do it even. That engine was heat cycled.)

In the end, you can pick how you want to break-in your engine. Personally, I want to get the most life out of my engine as possible even if it means a little handcap for the first gallon of life. (Beside driving skills win races not big engines.)

RE: How do you know you engine is running perfect?
 

Well i really don’t know which is best anymore. [&:] When idling the tanks what temps your engines get up to? I think this is the main point of running it in, Getting the temp up then letting it cool with the piston at bottom.

But doesn’t Stephen Bess’s method sound correct and makes perfect sense? Like what’s the theory to the traditional method? I have heard no theory backing the traditional method.

How do you guys know Stephen’s method lasts only 3 gallons? It depends on what fuel, and how lean and how hard someone pushes their engine.

I need answers! Because i have waisted about $500 AUD on eninges because of running it in wrong? and running it too rich. I want to get it right next time!
Jon

Thanks!

RE: How do you know you engine is running perfect?
 

the idea of the 'traditional' method is to keep it fairly cool but not cold and circulate plenty of oil to act as a barrier to the metal-metal contact and the stephen bess or picco method is to keep this contact to a minumum