Correct way to test engine pinch?
03-18-2009, 11:32 AM
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Correct way to test engine pinch?
I have a mach 427 with a truck I recently got. Was told the engine was just broken in. So with the glow plug out, I can turn the engine all the way over with just a little resistence at the top. Then with the glow plug in and I turn the engine over its pretty tight at the top. That sound good? Or should it be tight without the plug also. Thanks
03-18-2009, 12:09 PM
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RE: Correct way to test engine pinch?
It should be reasonably tight with the plug out. However, that's pretty subjective.
The only real way to check pinch is to remove the piston and sleeve from the engine, push the piston up into the sleeve and see where it stops. It should stop about 1/8" or so from the top of the sleeve. If it goes farther into the sleeve or even with the top or sticks out the top then the pinch is going or gone.
Does the engine run? If so is it easy to restart when it's hot? Running good cold but difficult or impossible to restart when hot would be a bad sign too.
The only real way to check pinch is to remove the piston and sleeve from the engine, push the piston up into the sleeve and see where it stops. It should stop about 1/8" or so from the top of the sleeve. If it goes farther into the sleeve or even with the top or sticks out the top then the pinch is going or gone.
Does the engine run? If so is it easy to restart when it's hot? Running good cold but difficult or impossible to restart when hot would be a bad sign too.
03-18-2009, 12:21 PM
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RE: Correct way to test engine pinch?
Ya it runs. Also it starts up fast when hot. I am having some tuning issues. So im going down the list of things it might be. Im sure I need a new clutch. It has the stock plastic shoes and one of the springs did look as tight as the others. They looked pretty beat up. I was thinkin about going back to platic ones just cause there alot cheaper, but they prob wont last long in this engine?
