OS 15 Tuning Problems

[DarthRacer]

Ok fellas, I need a little help here.
My OS .15 is giving me some problems.
1) Difficult to start
2) Stalls after letting off the throttle after a quick high speed run (tried adusting the idle to prevent this, but this makes the Maxx tranny want to engage)
3) Difficult to re-start when hot

Notes:
1) I have checked for air leaks - haven't found any (used air pressure from mouth)
2) Using a new OS A3 plug
3) Engine is easy to start when a lean condition is produced when all fuel is taken out of the tank and the engine is started to burn the fuel in the lines
4) LSN is set so the engine stalls after pinching the fuel line for 4 seconds
5) I am using a TRX .15 HSN because my OS needle broke
6) Using fuel from last year stored in a low humidity / room temp area - 10% Nitro

 

[KMN]

How was it broken in?

Sounds like a bad break in, or a mistuned engine... My first engine did the same thing since, being a man, I didnt bother reading the directions.

How little I knew about breaking a motor in.

 

[AoD]

Sounds like it could be on a last leg. Check the compression.. If the flywheel turns over really easy while cold, might as well rebuild. If not.. Set the carb up to stock, and restart the tuning process. Clean everything up, and try again.

Good luck

 

[DarthRacer]

It still has great compression.
I have started at factory specs - still not there yet.
Since my engine dosen't seem to be going over 220 degrees, maybe I'm running too rich.
I'm wondering about using the TRX HSN though. I have an OS carb layin around I should try out.

 

[AoD]

That would be the best bet. You never know if there is a "perfect" fit. Just a little difference can make a huge hassle. Try the other carb. That would be the best bet since the compression is good. Since you have taken the right procedures on everything else, that may be the cause.

Remember this little helpful hint. The most obvious reason, is usually the problem.

 

[Nitroaddict]

i agree - seems the problem is being caused by the traxxas part. Also - if it quites off throttle from a high speed run, and also at idle - it is TOO LEAN. i just had this problem, at a race last thursday. replace the traxxas part with the correct OS part. Would u put a chevy carb. on a Ford mustang? no. Also, reset the engine's settings to factory BREAK IN settings, and then begin to tune from there - using SMALL changes 1/16th at a time. read the thread i posted from a little while ago, listing the same problem u have. It is in this section with the title "I'm stumped! help me understand". The hints i got from it solved my problem. good luck ,and this should work.