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Tuning help

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B

black4x4

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Ok i got a huge problem with tuning today i went out with my t maxx to have a little fun but I have to tune it and this happens, when I start the truck the motor is pushing a lot like it wants to move but the idle is a stock setting (everything is at stock setting) and it wants to move and I shut it off and un-tighten the slipper clutch cause i thought it was grabbing and trying to move so after I started it back up and and let it warm back up a little and put it on the ground and started to rev it and it was sitting still so i went back to tighten it, start it up and same thing happen it was trying to move. I think i saw some smoke coming from the motor I don't know if it was the motor it self or burnt fuel from the pipe but it was around the motor. I was watching the temp but I think my temp reader thing is broken because i keep getting odd numbers

I think I will take to my local hobby shop let them tune it or whatever because I'm scared of my noob-ish skills that I'm gonna cook the motor

Specs if this helps
Tmaxx 4908
Trx 3.3
All around RPM arms
All around RPM shock towers
everything else bone stock

plz guys help me :(:(:(

-Thomas
 
Sounds like a case of the new engine break-in's. What does it do under throttle??? What it does at idle is of little use. It could be that the idle is a little high. Could be a rich LSN. Could be that your throttle trim isn't zeroed out. Please be a little more specific, and maybe think about loosing the "experienced RC driver" tag. JMO...
 
I am an experienced RC driver not tuner lol no i know my way around everything but tuning
ok my trim is on zero, I dont move it but the truck trys to move move not like creep a little, isn't it suppose to creep a tiny bit when the idle is close to tuned, but its trying to really move. I think Metalhead Matt is right its a air leak, everything is at stock settings I don't understand Hsn is 4 turns out from close and Lsn is flush with inner rim and Idle is 1mm-1.5mm open i know all this. How can I tell if its a air leak? When its under throttle it speeds up and stuff but it keeps going if I release the trigger

I'm gonna try that air leak test with the soapy water
 
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Air leaks do not generally manifest themselves at idle that way--unless the RPM's are screaming at idle. It is normal for an overly-rich tuned engine (read new engine) to "surge" at idle. If you are just breaking in the engine DO NOT worry about it right now. You want a slightly rich condition to do your break-in. If the engine is broken in--and I don't know 'cause you never said--then you can start to lean it out a 1/16 at a time to tune for speed and that SHOULD get rid of the "surge" at the same time. If it doesn't then look for an air leak, but keep in mind air leaks usually show themselves by leaning your tune out on the top end.

I would still not proclaim myself as experienced. Again, JMO...
 
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So did you lean the tune a tad to see if that helped??? If it didn't did you perform the leak test (although I still don't think it is an air leak but anything is possible)?
 
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I'm gonna try the leak test one day I dont have much homework and Ill write back thanks for the help
 

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