Idle Issues!!! I'm Stumped!

[Maldopa80]

The motor is a AE 15 team Associated.

Broke in the new piston this morning, ran like a champ, wheelies and dirt rooster tails. No stalls nothing. used 2 fill bottles worth of gas. Idles great. take a good break ran some errands and come back to kill out some more fuel and get some jumps in and the car starts this idle issue that has happen before but i thought i had fixed it with a clean rebuild and tune.

When the rpm's are up the idle seems to stick a bit high when i release the trigger that said gotta hold the break to keep still. It will return to normal idle after bit then go back to the higher rpm's and run away again. its erratic on how long it will stay in a normal idle state and a higher Rpm state but it will flip flop back n forth.

I've watched the servo for "twitching" and the tune on the car is spot on, release the trigger servo go's to neutral hit the brakes the idle remains the same. full throttle on trigger and carb opening is fully open. Really faint smoke on idle, good smoke on acceleration. Hottest temp on Head was 176f Normally ran 130-150f.

Go easy on my if its somethin simple I'm only 2 months in this hobby!!!! Please HELP!!!!

 

[avelciario]

check the idle gap its seems too big plus your lsn on the rich side. Try to make idle screw 1mm then if the idle drops lean the lsn to the desired idle. Your temp is too low but don't tune your car on temp its just a guide. For me all my engine runs 220-240F only. Don't worry too many guys out there to help you about rc problems and I've learned to tuned my rigs with all the suggestion and comments. Thanks to all.

 

[Phins Fan]

Did you seal the motor after the rebuild? Airleaks can develop quickly and over time that will cause erratic tunes/idles. Just a thought anyway

 

[Maldopa80]

No i didn't seal anything, just put it all back to together. ill check the tune settings once more. then if that does not work ill do a air leak test. thanks fellas!!!

 

[Phins Fan]

When I first got into Nitro RC I learned how to seal using this vid:

[ame="http://www.youtube.com/watch?v=6xwDy-I0Z4I"]How to seal an RC engine from air leaks - YouTube[/ame]

 

[joshman1204]

Sounds like the LSN is lean. If it is revving up on your and trying to run away that would indicate a lean LSN assuming you have the proper idle gap.

Try leaning your LSN in small increments until the idle drops to a reasonable level.

Check out the tuning flowchart on this site and also the performance tuning guide on the ERCM site. Those two guides combined will make your life a lot easier.

 

[Maldopa80]

Fixed the air leak fellas! Man it was easy. All I had to do was adjust the motor lean. So lean I locked the piston broke the rod burned out a crank shaft barring. Best 45 min I had RC'n ever! All that said I just went ahead and bought a new motor... funny thing tho, loved every min of it!