how to check if pinch is good on an engine?
#1
how to check if pinch is good on an engine?
i just received a hyper.21 that is used and would like to know how to check for pinch.
#3
thanks for the info
#6
thanks guys it seems to have a little pinch left in it then.
#7
Tech Regular
Not all engines are bad that have little pinch. I have a new picco that has little pinch out of the box compared to a RB. The picco breaks in much easier=faster.
#9
can i just ask what is pinch?
#10
Tech Elite
iTrader: (67)
Because nitro engines do not have rings, the piston and sleeve are very tight at the top of the stroke to keep a tight seal so power is not lost. When most engines are new they have alot of pinch and turn over very hard. With break in the piston and sleeve wear in together. After many gallons of fuel or if a motor gets dirt in it the motor will not run very good. This is because there is no pinch left and the piston is not tight in the sleeve anymore. Most times it will run but won't idle and will die. There are a few people like myself that can use equipment and squeeze the sleeve and make the fit tight again. So for only $15.00 you get a motor that runs like new again. (if everything else is good in the motor)
Rex
Rex
#11
Oh thanks. I noticed that with my new eb4. Was very tight to turn over, now a much better
#12
Do the flop test. Hold onto the flywheeland let the weight of the engine fall to the side. If the compression is enough it will not flop over, or turn over. It will stick and hold the weight of the engine.
#13
Thats how I usually check. If it falls right over with little or no hold. A tell tail sign also is the motor has a very erratic idle, or won't idle...
#14
Tech Rookie
When I do the flop test should the engine not roll over at all? Or is it ok if it falls over slowly? Thanks for the info.
#15
I wish someday an engine manufacturer use seal ring(s) on the piston head ( just like in real engines ), ..... so we don't have to replace piston sleeve frequently like we do today.