can't find the recommended 11x10 break in prop anywhere
05-01-2003, 05:07 AM
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can't find the recommended 11x10 break in prop anywhere
Wow, all this reading and studying of post/threads. I didn't read this hard during my 4 years of college. 
05-01-2003, 06:12 AM
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can't find the recommended 11x10 break in prop anywhere
Forget going WOT using the needle to keep it under 4-5K RPMs for the break-in runs. This may not be possible.
Just open the needle up to slobbery rich requiring a glow heater to keep her running. 5 turns sounds good on the TT 91 FS.
Airflow over the engine will have a negligible cooling effect at the initial break-in settings. The heat generated running that slow won't be a lot. The cooling from alcohol evaporation running that rich will keep the engine so cool you can hold your hand on it for the whole tank-full.
Some things to do:
You might want to check for trash in the crankcase.
Check for loose screws. Tighten them up.
Be careful with the front valve cover screw. The metal in the head is thin where it's threaded to accept the screw. These strip easily.
Remove the valve cover and squirt some oil down the pushrod tubes and over the rocker arms - You don't need a lot but do get a few drops in there. Check the valve clearance while you have the cover off.
Run it on a bench. It's so much easier to manage that way.
Keep clear of where the prop may go if it comes off. Back-fires and pre-ignition will sling the prop off and you don't want to get in it's way.
Earplugs help, too.
Keep the RPMs down and the mixture REALLY rich for a few runs.
Let the engine COMPLETELY cool between runs.
Over several more runs gradually lean the engine out (what does the book say ? 1/4 turn per tank?) while gradually increasing the RPMs over several tanks. Take your time and use up some fuel doing this.
Once you have a 3/4 gallon or so through the engine (doesn't take so long running that rich) you're probably approaching some decent RPMs. This would be a good time to switch to a 14-6 or so prop to put some load on it. Otherwise you may over-rev while you're trying to find the proper needle setting. Do this before you over-rev.
I've broken in a couple and had to fiddle with one to get the cam timing right. I ran about a 3/4 gallon through each one before I leaned them enough to hit some decent RPMs. Then I started tweaking the low-speed needle for reliable idle. I believe I had about 5 quarts through each before I got both the low-speed and high-speed adjusted for optimum running with a stable idle without any load-up. At that point, it's time to re-adjust the valves.
I haven't tried any plugs other than OS F which works fine. Others may work, too - dunno.
If you've run several tanks through your 4-stroke and find that it runs great up to about 1/2 throttle then sputters and dies when you open it up regardless of needle settings, then your valve timing may be off. Remove the cam cover and check the marks. One of mine was off and I've helped a couple other people here already with the same problem. Seems that TT's ISO 9001 rating doesn't mean much with respect to valve timing correctness from the factory. :/
Boy that was long-winded...
Just open the needle up to slobbery rich requiring a glow heater to keep her running. 5 turns sounds good on the TT 91 FS.
Airflow over the engine will have a negligible cooling effect at the initial break-in settings. The heat generated running that slow won't be a lot. The cooling from alcohol evaporation running that rich will keep the engine so cool you can hold your hand on it for the whole tank-full.
Some things to do:
You might want to check for trash in the crankcase.
Check for loose screws. Tighten them up.
Be careful with the front valve cover screw. The metal in the head is thin where it's threaded to accept the screw. These strip easily.
Remove the valve cover and squirt some oil down the pushrod tubes and over the rocker arms - You don't need a lot but do get a few drops in there. Check the valve clearance while you have the cover off.
Run it on a bench. It's so much easier to manage that way.
Keep clear of where the prop may go if it comes off. Back-fires and pre-ignition will sling the prop off and you don't want to get in it's way.
Earplugs help, too.
Keep the RPMs down and the mixture REALLY rich for a few runs.
Let the engine COMPLETELY cool between runs.
Over several more runs gradually lean the engine out (what does the book say ? 1/4 turn per tank?) while gradually increasing the RPMs over several tanks. Take your time and use up some fuel doing this.
Once you have a 3/4 gallon or so through the engine (doesn't take so long running that rich) you're probably approaching some decent RPMs. This would be a good time to switch to a 14-6 or so prop to put some load on it. Otherwise you may over-rev while you're trying to find the proper needle setting. Do this before you over-rev.
I've broken in a couple and had to fiddle with one to get the cam timing right. I ran about a 3/4 gallon through each one before I leaned them enough to hit some decent RPMs. Then I started tweaking the low-speed needle for reliable idle. I believe I had about 5 quarts through each before I got both the low-speed and high-speed adjusted for optimum running with a stable idle without any load-up. At that point, it's time to re-adjust the valves.
I haven't tried any plugs other than OS F which works fine. Others may work, too - dunno.
If you've run several tanks through your 4-stroke and find that it runs great up to about 1/2 throttle then sputters and dies when you open it up regardless of needle settings, then your valve timing may be off. Remove the cam cover and check the marks. One of mine was off and I've helped a couple other people here already with the same problem. Seems that TT's ISO 9001 rating doesn't mean much with respect to valve timing correctness from the factory. :/
Boy that was long-winded...
05-01-2003, 06:06 PM
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can't find the recommended 11x10 break in prop anywhere
Hello!
Come on guys!
If you have been around for many years in this wonderful hobby/sport you know that our glowengines get most of their cooling from the fuel and not the air!
A 14x6 or 13x8 APC prop is what nearly every sportplane pilot
will use for best performance. when it comes to flying ......yes I know that in pattern planes they used different size props like 11x10, 11x12 and so on but for running-in an sportflying with an ordinary .90 forstroke lika OS, Saito or TT a 14x6 prop would be much better to use than a 11" prop. It will be easier to flip start by hand ...I still do flip start my engines occasionaly and it will be a better "load"for the engine, steadier and have more mass, then a small 11" prop
When Saito says not to rew over 4000 or 5000 rpm initially is not written in stone ..what they mean by that ..their intention.... is that the owners of their engines should not put a too heavy load on the engine initially! That means that they does not want owners to rew their engines too much over 10000 rpm initially and and set the highspeedneedle too lean so the engine overheats.
They also want to protect the engine from too heavy handed fiddlers that dont know anything about engines, that put on too large props on their engines (load them down too much) so that the engine owerheats.
What is important with ANY modelglow engine using a ring is to run it rich at low rpm!! be it 4000 or 7000 does not matter!
It is also vital that that the rpm is set with the highspeed needle not with the throttle drum itself!
If you can't have the engine run as low as 4000rpm with the glowclip off ......then just lean the highspeed needle in somewhat so the rpm gets a little higher....!!!RPM is not that vital!!!
Using the throttle drum to adjust the rpm is bad because sometimes newcomers can't hear when the engine goes lean(get very warm).....and engine can go lean even at 4000rpm.
Running rich is vital to a ringed engine and to load the engine lightly at first ....be that at 4000 5000 or 8000rpm does not matter.
Regards!
Jan K
Sweden
20 years of pylonflying
Come on guys!
If you have been around for many years in this wonderful hobby/sport you know that our glowengines get most of their cooling from the fuel and not the air!
A 14x6 or 13x8 APC prop is what nearly every sportplane pilot
will use for best performance. when it comes to flying ......yes I know that in pattern planes they used different size props like 11x10, 11x12 and so on but for running-in an sportflying with an ordinary .90 forstroke lika OS, Saito or TT a 14x6 prop would be much better to use than a 11" prop. It will be easier to flip start by hand ...I still do flip start my engines occasionaly and it will be a better "load"for the engine, steadier and have more mass, then a small 11" prop
When Saito says not to rew over 4000 or 5000 rpm initially is not written in stone ..what they mean by that ..their intention.... is that the owners of their engines should not put a too heavy load on the engine initially! That means that they does not want owners to rew their engines too much over 10000 rpm initially and and set the highspeedneedle too lean so the engine overheats.
They also want to protect the engine from too heavy handed fiddlers that dont know anything about engines, that put on too large props on their engines (load them down too much) so that the engine owerheats.
What is important with ANY modelglow engine using a ring is to run it rich at low rpm!! be it 4000 or 7000 does not matter!
It is also vital that that the rpm is set with the highspeed needle not with the throttle drum itself!
If you can't have the engine run as low as 4000rpm with the glowclip off ......then just lean the highspeed needle in somewhat so the rpm gets a little higher....!!!RPM is not that vital!!!
Using the throttle drum to adjust the rpm is bad because sometimes newcomers can't hear when the engine goes lean(get very warm).....and engine can go lean even at 4000rpm.
Running rich is vital to a ringed engine and to load the engine lightly at first ....be that at 4000 5000 or 8000rpm does not matter.
Regards!
Jan K
Sweden
20 years of pylonflying
05-01-2003, 06:23 PM
#30
can't find the recommended 11x10 break in prop anywhere
Jaka,
The 11-10 prop is not my idea, it is the recommended break in prop by ThunderTiger. And when leaned out the air flow is the principle cooling medium. The TT definately runs hotter with the 14-6 ON THE BENCH than the 11-10 even though it turns more R's with the 11-10. I use the starter, especially when breaking in the engine.
The 11-10 prop is not my idea, it is the recommended break in prop by ThunderTiger. And when leaned out the air flow is the principle cooling medium. The TT definately runs hotter with the 14-6 ON THE BENCH than the 11-10 even though it turns more R's with the 11-10. I use the starter, especially when breaking in the engine.
05-01-2003, 08:21 PM
#31
Senior Member
Break-in
I can only agree with Jan K and with Sport_Flyer.
I also agree with Thunder Tiger about their specified break-in prop. While the methanol affects a good proportion of the cooling, by evaporating, the low load, high airspeed prop does have more than a marginal cooling effect.
I cannot agree on the 4,000-5,000 RPM "law". First because the cam and lifters can become galled and ruined from low RPM running when new. Also, when an engine is running very rich and directly cooled by methanol oozing all over the sleeve, even much higher RPM will not cause the engine any harm, whatsoever. Running as described, full throttle, the engine will probably get to about 7,000 RPM.
Providing TT has given the hardened steel sleeve, the correct crosshatch pattern, to retain oil properly and to enhance seating, the cast iron compression ring will have seated itself well enough after the first 20-30 minutes of break-in. If the TT's ring is of the chromed variety, 10 minutes longer will be in order.
I don't think anyone should just spill 3/4 of a gallon of fuel, through the engine, doing nothing.
After 30 minutes the modeler should try to see if the engine can hold a steady, long duration, correct mixture, idle. Without the glow starter on the plug and with a good recovery to higher RPM.
If it is affirmative, the next thing is to lean the mixture to max-minus-1,000 RPM, If the engine holds this RPM steady, without any signs of overheating, it is broken-in. It is recommended to keep it this rich for 4-6 flights. That is it.
If the engine cannot idle well yet, run rich for another 10 minutes and try again.
Still. I can't imagine why TT would describe the procedure as they do.
Sincerely,
I also agree with Thunder Tiger about their specified break-in prop. While the methanol affects a good proportion of the cooling, by evaporating, the low load, high airspeed prop does have more than a marginal cooling effect.
I cannot agree on the 4,000-5,000 RPM "law". First because the cam and lifters can become galled and ruined from low RPM running when new. Also, when an engine is running very rich and directly cooled by methanol oozing all over the sleeve, even much higher RPM will not cause the engine any harm, whatsoever. Running as described, full throttle, the engine will probably get to about 7,000 RPM.
Providing TT has given the hardened steel sleeve, the correct crosshatch pattern, to retain oil properly and to enhance seating, the cast iron compression ring will have seated itself well enough after the first 20-30 minutes of break-in. If the TT's ring is of the chromed variety, 10 minutes longer will be in order.
I don't think anyone should just spill 3/4 of a gallon of fuel, through the engine, doing nothing.
After 30 minutes the modeler should try to see if the engine can hold a steady, long duration, correct mixture, idle. Without the glow starter on the plug and with a good recovery to higher RPM.
If it is affirmative, the next thing is to lean the mixture to max-minus-1,000 RPM, If the engine holds this RPM steady, without any signs of overheating, it is broken-in. It is recommended to keep it this rich for 4-6 flights. That is it.
If the engine cannot idle well yet, run rich for another 10 minutes and try again.
Still. I can't imagine why TT would describe the procedure as they do.
Sincerely,
05-02-2003, 12:16 AM
#32
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Re: Break-in
Originally posted by DarZeelon
I can only agree with Jan K and with Sport_Flyer.
I also agree with Thunder Tiger about their specified break-in prop. While the methanol affects a good proportion of the cooling, by evaporating, the low load, high airspeed prop does have more than a marginal cooling effect.
I cannot agree on the 4,000-5,000 RPM "law". First because the cam and lifters can become galled and ruined from low RPM running when new. Also, when an engine is running very rich and directly cooled by methanol oozing all over the sleeve, even much higher RPM will not cause the engine any harm, whatsoever. Running as described, full throttle, the engine will probably get to about 7,000 RPM.
Providing TT has given the hardened steel sleeve, the correct crosshatch pattern, to retain oil properly and to enhance seating, the cast iron compression ring will have seated itself well enough after the first 20-30 minutes of break-in. If the TT's ring is of the chromed variety, 10 minutes longer will be in order.
I don't think anyone should just spill 3/4 of a gallon of fuel, through the engine, doing nothing.
After 30 minutes the modeler should try to see if the engine can hold a steady, long duration, correct mixture, idle. Without the glow starter on the plug and with a good recovery to higher RPM.
If it is affirmative, the next thing is to lean the mixture to max-minus-1,000 RPM, If the engine holds this RPM steady, without any signs of overheating, it is broken-in. It is recommended to keep it this rich for 4-6 flights. That is it.
If the engine cannot idle well yet, run rich for another 10 minutes and try again.
Still. I can't imagine why TT would describe the procedure as they do.
Sincerely,
I can only agree with Jan K and with Sport_Flyer.
I also agree with Thunder Tiger about their specified break-in prop. While the methanol affects a good proportion of the cooling, by evaporating, the low load, high airspeed prop does have more than a marginal cooling effect.
I cannot agree on the 4,000-5,000 RPM "law". First because the cam and lifters can become galled and ruined from low RPM running when new. Also, when an engine is running very rich and directly cooled by methanol oozing all over the sleeve, even much higher RPM will not cause the engine any harm, whatsoever. Running as described, full throttle, the engine will probably get to about 7,000 RPM.
Providing TT has given the hardened steel sleeve, the correct crosshatch pattern, to retain oil properly and to enhance seating, the cast iron compression ring will have seated itself well enough after the first 20-30 minutes of break-in. If the TT's ring is of the chromed variety, 10 minutes longer will be in order.
I don't think anyone should just spill 3/4 of a gallon of fuel, through the engine, doing nothing.
After 30 minutes the modeler should try to see if the engine can hold a steady, long duration, correct mixture, idle. Without the glow starter on the plug and with a good recovery to higher RPM.
If it is affirmative, the next thing is to lean the mixture to max-minus-1,000 RPM, If the engine holds this RPM steady, without any signs of overheating, it is broken-in. It is recommended to keep it this rich for 4-6 flights. That is it.
If the engine cannot idle well yet, run rich for another 10 minutes and try again.
Still. I can't imagine why TT would describe the procedure as they do.
Sincerely,
Breaking in my TT's for the first few runs the engines were so cool they didn't even feel warm to the touch. There is NO WAY airflow will have any significant cooling effect running like this. If there ain't no temperature differential, there ain't no thermal transfer. Once you start leaning them out, sure.
I'm no supporter of the "RPM law" but if the manufacturers (all of them) tell you this, I'll play nice and abide by it. Keeping the revs down certainly doesn't hurt anything during the early runs, either. Nobody is going to accuse me of having to send one back because I over-revved it on the first few runs. Nope. Not gonna happen. Give those newly-machined surfaces a chance to get to know each other.
No way are pushrods and lifters going to get galled at slobbery rich temperatures. It just ain't gonna happen.
'scuse me? Did I say spill 3/4 gallon of fuel through the engine doing nothing? Duh..... Why not just pour a whole gallon over it? I believe what I was saying is: if you take your time the engine will be leaned out enough to be hitting some decent revs after 3/4 gallon or so. It will take at least a half gallon to get the engine leaned out if you take your time and don't lean the engine out too quickly. The fuel is sucked down quickly when they're slobbery rich
Your ringed engine will appreciate it if you don't rush the break-in. If you want to proceed more quickly, have fun!
cheers.
05-02-2003, 03:50 AM
#33
Senior Member
can't find the recommended 11x10 break in prop anywhere
BGI,
In past times auto manufacturers told you not to exceed 50% of maximum RPM, during the first 1,000 miles.
Now, when crosshatch honing is fully evolved, the same manufacturers tell you, not to excite 75% of maximum RPM and not to use full throttle for more than a few seconds, during the first 500 miles... Some, wrongfully, do not tell you anything...
The TT has a great crosshatch treated bore. What method would you choose?
When you broke-in your TT, you didn't do it without a propeller on, did you? You were noticing the cooling effect of both the rich mixture and the prop.
Camshaft(s) and lifters are not in a place that gets doused with raw fuel. Read what cam manufacturers say about initial break-in in http://www.cranecams.com.
Running an engine slobberingly rich is good (for the engine) for the first 20-30 minutes. After that, it is good for no one and nothing.
Being overcautious beyond the necessary duration, will only waste fuel. It will not break the engine in better.
For most ringed two strokes, only the first two-three tanks should be slobberingly rich. That is less than a quart of fuel.
A four-stroke .90 doesn't eat more, perhaps even less.
Your ringed engine will not appreciate an extra rich mixture after it no longer needs it. It will not thank you.
Sincerely,
In past times auto manufacturers told you not to exceed 50% of maximum RPM, during the first 1,000 miles.
Now, when crosshatch honing is fully evolved, the same manufacturers tell you, not to excite 75% of maximum RPM and not to use full throttle for more than a few seconds, during the first 500 miles... Some, wrongfully, do not tell you anything...
The TT has a great crosshatch treated bore. What method would you choose?
When you broke-in your TT, you didn't do it without a propeller on, did you? You were noticing the cooling effect of both the rich mixture and the prop.
Camshaft(s) and lifters are not in a place that gets doused with raw fuel. Read what cam manufacturers say about initial break-in in http://www.cranecams.com.
Running an engine slobberingly rich is good (for the engine) for the first 20-30 minutes. After that, it is good for no one and nothing.
Being overcautious beyond the necessary duration, will only waste fuel. It will not break the engine in better.
For most ringed two strokes, only the first two-three tanks should be slobberingly rich. That is less than a quart of fuel.
A four-stroke .90 doesn't eat more, perhaps even less.
Your ringed engine will not appreciate an extra rich mixture after it no longer needs it. It will not thank you.
Sincerely,
05-02-2003, 01:53 PM
#34
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can't find the recommended 11x10 break in prop anywhere
Dar,
I'd choose the manufacturer's recommended method. I believe they know more than me. After all, they designed and built the engine.
For the cooling, I'll just be stubborn and repeat that if the engine doesn't feel warm (at least for the first few tanks) then airflow isn't cooling it. If it doesn't feel warm then how can airflow cool it?
I looked around on crane's site and searched a bit and didn't find much about break-in which would apply here except confirmation that we need to run some oil down the pushrod tubes. Maybe I missed it?
With the needle set 5.25 turns out, my TT's were sucking down a 14 oz tank in 5 mins. Gradual leaning reduced the fuel consumption to something reasonable, so a half gallon was gone pretty quickly. Further tweaking of the idle and high-speed needles will take some fuel, too.
I believe I left out some detail by not explaining enough in that super-long-winded post. A good portion of the bench time I used up tuning and continuing break-in for a good reliable idle. While 30 mins is excessive time running slobbering rich, it's not enough break-in to obtain a reliable idle. I don't like dead-sticks in planes I've spent months building, so I get an engine running at reliable idle and good transition before it goes on the plane. From my limited experience, this isn't possible until you've put about a gallon through the TT 91's. Someone more skilled than me might do better.
cheers.
I'd choose the manufacturer's recommended method. I believe they know more than me. After all, they designed and built the engine.
For the cooling, I'll just be stubborn and repeat that if the engine doesn't feel warm (at least for the first few tanks) then airflow isn't cooling it. If it doesn't feel warm then how can airflow cool it?
I looked around on crane's site and searched a bit and didn't find much about break-in which would apply here except confirmation that we need to run some oil down the pushrod tubes. Maybe I missed it?
With the needle set 5.25 turns out, my TT's were sucking down a 14 oz tank in 5 mins. Gradual leaning reduced the fuel consumption to something reasonable, so a half gallon was gone pretty quickly. Further tweaking of the idle and high-speed needles will take some fuel, too.
I believe I left out some detail by not explaining enough in that super-long-winded post. A good portion of the bench time I used up tuning and continuing break-in for a good reliable idle. While 30 mins is excessive time running slobbering rich, it's not enough break-in to obtain a reliable idle. I don't like dead-sticks in planes I've spent months building, so I get an engine running at reliable idle and good transition before it goes on the plane. From my limited experience, this isn't possible until you've put about a gallon through the TT 91's. Someone more skilled than me might do better.
cheers.
05-02-2003, 02:22 PM
#35
Senior Member
Cam break-in
BGI,
Sorry about the referral. The changed the sit long ago, but I must have fallen asleep since my hotrodding days.
Try: http://engineparts.com/Motorhead/tec.../cambreak.html
It states the engine must be run at relatively high speed, because low speeds cause wear and galling.
Models have not yet resorted to roller cams...
I said I don't agree with TT about that extra long, extra slow ring and sleeve break-in. You can follow their instruction if you feel safer doing it.
Sincerely,
Sorry about the referral. The changed the sit long ago, but I must have fallen asleep since my hotrodding days.
Try: http://engineparts.com/Motorhead/tec.../cambreak.html
It states the engine must be run at relatively high speed, because low speeds cause wear and galling.
Models have not yet resorted to roller cams...
I said I don't agree with TT about that extra long, extra slow ring and sleeve break-in. You can follow their instruction if you feel safer doing it.
Sincerely,
05-04-2003, 08:49 PM
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brake in
recommended engine brake in sequence
fill fule tank start engine run low seed for 2 Minuit's and take off.
climb untill air is clear and cool.repeat until gas can is empty
fill fule tank start engine run low seed for 2 Minuit's and take off.
climb untill air is clear and cool.repeat until gas can is empty
11-14-2003, 07:26 AM
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RE: can't find the recommended 11x10 break in prop anywhere
Hi!
Thunder Tiger has these thourough recommendations so that no heavy handed fiddlers shouldn't do anything wrong with their engines and then blame TT for selling a bad product.......
Running in is NOT ..I repeat not rocket sience...running in could be done in several ways!
The most important thing to remember when running-in an engine is to let it reach working temperature fast ...and let it have enough lubrication so that the inner, working parts receives enough lubrication and to have all the working parts(piston/pistonring -cylinder) get mated to each other.
Wheter you use a 11x12, 13x8, 14x6 or 15x4 APC is not that important. But I do recommend APC props! Master A is no good!
Rpm is not critical 5000rpm or 7000rpm is of no importance..... the important thing to remember for every ringed or lapped engine is that you run it at a fairly rich setting the firtst fueltanks...And that you always adjust the rpm with the highspeed needle. Not with the throttle drum!
The fuel itself is the most impotant cooling medium for glowengines...not the air!
Regards!
Jan Karlsson
Thunder Tiger has these thourough recommendations so that no heavy handed fiddlers shouldn't do anything wrong with their engines and then blame TT for selling a bad product.......
Running in is NOT ..I repeat not rocket sience...running in could be done in several ways!
The most important thing to remember when running-in an engine is to let it reach working temperature fast ...and let it have enough lubrication so that the inner, working parts receives enough lubrication and to have all the working parts(piston/pistonring -cylinder) get mated to each other.
Wheter you use a 11x12, 13x8, 14x6 or 15x4 APC is not that important. But I do recommend APC props! Master A is no good!
Rpm is not critical 5000rpm or 7000rpm is of no importance..... the important thing to remember for every ringed or lapped engine is that you run it at a fairly rich setting the firtst fueltanks...And that you always adjust the rpm with the highspeed needle. Not with the throttle drum!
The fuel itself is the most impotant cooling medium for glowengines...not the air!
Regards!
Jan Karlsson
11-14-2003, 07:58 AM
#39
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RE: can't find the recommended 11x10 break in prop anywhere
ORIGINAL: jaka
Wheter you use a 11x12, 13x8, 14x6 or 15x4 APC is not that important. But I do recommend APC props! Master A is no good!
Wheter you use a 11x12, 13x8, 14x6 or 15x4 APC is not that important. But I do recommend APC props! Master A is no good!
The fuel itself is the most impotant cooling medium for glowengines...not the air!
11-14-2003, 08:41 AM
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RE: can't find the recommended 11x10 break in prop anywhere
One thing you don't want to do is use Jazzy's method, if you run it wot with the mixture richened down to 5,000 rpm, the engine will be so cold it won't break in a hundred years. It needs to be somewhat warm to simulate the tolerances it will run at after break in. I set the high speed mixture for each rpm that I run the engine as someone suggested above, that way I don't have fuel just going through the engine for nothing.
11-14-2003, 10:08 AM
#41
Senior Member
RE: can't find the recommended 11x10 break in prop anywhere
I agree with all here that think the method of break-in from Thunder Tiger unnecessary and wasteful (in both time and fuel).
Thunder Tiger engines are made from materials, no different from those used by other model engine manufacturers.
The tolerances they use are also identical. Their engineers studied in the same universities as all other engineers.
I invite Thunder Tiger to prove to me, that if I do the break-in at 7,500 RPM, with a low load prop, extremely rich for the first 10 minutes (with glow power) and just rich for the next 20-30, it will not be as well broken-in, or will not have as long a life, or will not have the reliability that is achieved with their method.
Thunder Tiger engines are made from materials, no different from those used by other model engine manufacturers.
The tolerances they use are also identical. Their engineers studied in the same universities as all other engineers.
I invite Thunder Tiger to prove to me, that if I do the break-in at 7,500 RPM, with a low load prop, extremely rich for the first 10 minutes (with glow power) and just rich for the next 20-30, it will not be as well broken-in, or will not have as long a life, or will not have the reliability that is achieved with their method.
11-14-2003, 01:28 PM
#42
RE: can't find the recommended 11x10 break in prop anywhere
ORIGINAL: DarZeelon
I agree with all here that think the method of break-in from Thunder Tiger
unnecessary and wasteful (in both time and fuel).
I agree with all here that think the method of break-in from Thunder Tiger
unnecessary and wasteful (in both time and fuel).
myself, or why it would take almost a gallon of fuel to get those things to idle.
Running that sloppy rich....it would take forever to seat the ring. [X(] Maybe
it's all just a product liability thing....they don't want the motors cooked by
new "needle tweakers"....right off the bat....
Dave.
11-14-2003, 01:59 PM
#43
RE: can't find the recommended 11x10 break in prop anywhere
Thunder Tiger engines are made from materials, no different from those used by other model engine manufacturers.
The tolerances they use are also identical. Their engineers studied in the same universities as all other engineers.
Maybe thats why the Saito break in proceedure is almost the same? I think over reving it may not be so good for the cam. The initial run for our automobiles is done at the factory. I recall lubing the cam with moly grease and letting it run at a fast idle for a few minutes. I agree that you can probably do just fine without it or with a differant prop, but it works fine so why mess with it? You only run a tank or so at a very rich mixture. Then you start leaning it out. It still takes well over a gallon of fuel to break in a TT 4S, same with Saito.
The tolerances they use are also identical. Their engineers studied in the same universities as all other engineers.
Maybe thats why the Saito break in proceedure is almost the same? I think over reving it may not be so good for the cam. The initial run for our automobiles is done at the factory. I recall lubing the cam with moly grease and letting it run at a fast idle for a few minutes. I agree that you can probably do just fine without it or with a differant prop, but it works fine so why mess with it? You only run a tank or so at a very rich mixture. Then you start leaning it out. It still takes well over a gallon of fuel to break in a TT 4S, same with Saito.
11-14-2003, 02:09 PM
#44
RE: can't find the recommended 11x10 break in prop anywhere
ORIGINAL: Flyboy Dave
Dar's....I've never been able to understand the crazy break-in procedure
myself, or why it would take almost a gallon of fuel to get those things to idle.
Running that sloppy rich....it would take forever to seat the ring. [X(] Maybe
it's all just a product liability thing....they don't want the motors cooked by
new "needle tweakers"....right off the bat....
Dave.
ORIGINAL: DarZeelon
I agree with all here that think the method of break-in from Thunder Tiger
unnecessary and wasteful (in both time and fuel).
I agree with all here that think the method of break-in from Thunder Tiger
unnecessary and wasteful (in both time and fuel).
myself, or why it would take almost a gallon of fuel to get those things to idle.
Running that sloppy rich....it would take forever to seat the ring. [X(] Maybe
it's all just a product liability thing....they don't want the motors cooked by
new "needle tweakers"....right off the bat....
Dave.
11-14-2003, 02:43 PM
#45
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
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RE: can't find the recommended 11x10 break in prop anywhere
Hi!
Okey, Okey guys!
I was in a hurry when I sent my latest message....Ofcourse APC props is no better then any other prop when running in an engine.
But hope that you use them afterwards or any other GOOD propeller...like the Graupner Cam-prop or the Australian Bolly props or German Menz wood props or Chech Mejzlic carbon props ...but please not Master Airscrew props.......Can't understand why people use inferior propellers when there is such good props on the market.......Have heard a sport pilot saying:
" MA prop looks like the real thing" ...Who cares if it so........Do some of you like bad performance??! it's what happens in the air what counts and MA props are not I repeat not as good performance wise as the other props mentioned both regarding noice and general flying performance.
Regards!
Jan Karlsson
Pylonracer
Sweden
Okey, Okey guys!
I was in a hurry when I sent my latest message....Ofcourse APC props is no better then any other prop when running in an engine.
But hope that you use them afterwards or any other GOOD propeller...like the Graupner Cam-prop or the Australian Bolly props or German Menz wood props or Chech Mejzlic carbon props ...but please not Master Airscrew props.......Can't understand why people use inferior propellers when there is such good props on the market.......Have heard a sport pilot saying:
" MA prop looks like the real thing" ...Who cares if it so........Do some of you like bad performance??! it's what happens in the air what counts and MA props are not I repeat not as good performance wise as the other props mentioned both regarding noice and general flying performance.
Regards!
Jan Karlsson
Pylonracer
Sweden
11-14-2003, 11:19 PM
#46
RE: can't find the recommended 11x10 break in prop anywhere
...Who cares if it so........
11-16-2003, 07:50 PM
#47
Senior Member
Join Date: Dec 2002
Location: md.
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RE: can't find the recommended 11x10 break in prop anywhere
I firmly believe one of the most important steps in break in of any four stroke that was not mentioned in this thread is to really lube up the bottom and top end before the initial run. Other than that I never ran in my tt 91 as richly as they recomended or with the 11/10 prop.
