traxxas 3.3 piston locked up

[rchambers]

I purchased a new 3.3 installed on t max i put on and electric start so i cranked it over a few times just to make sure all ok. when i got all finished and ready to start the beak in the motor was locked up. I took off the head and tried to crank it and it cranked but the sleeve moves up and down if i put the head back on it locks up. Whats happened? Its never been started.

 

[Scrogg]

The piston is stuck at the pinch zone of the sleeve. Take the head back off and let it push the sleeve up. Heat up the sleeve with a hair dryer or heat gun, drop some oil on the piston top. GENTLY try top pull the sleeve off the piston and out of the engine.
Do not use pliers on the sleeve, you'll ruin it.
OR put it all back together. Heat it up and put a set of channel locks on the flywheel and rotate the piston back down.
To prevent this from happening again, preheat the engine before you start it. Sounds like you got a nice tight one there, nothing wrong with it.
Make sure you EZ start battery is a strong one fully charged.

 

[rchambers]

thanks, i'll let you know tommorrow the out come,

 

[rchambers]

it worked thanks for the info.

 

[olds97_lss]

It's a good idea to put the piston at BDC (bottom dead center) of the stroke when it's not running. As the engine cools back down, the sleeve shrinks a bit. Keeping the piston at the bottom below the pinch zone in theory helps prolong engine life. If for nothing else, it helps avoid getting the piston stuck for the next run.

 

[KROGOTH]

I had the same issue with the TRX 3.3 on my Slayer. Once break in was done, it wouldnt do that anymore. Its just a problem caused by a tight pistion. All it took for me was a well charged EZ Start battery and when it locked at the top, turning the flywheel to put it at BDC and trying again.