Compression check?
Compression check? Just like the title says, ive been lookin through forums trying to find a post and can not find one. My car was miss shifted 2-3-2 and over revved. Bent 7 pushrods which i have replaced already but im afraid of wether or not a valve has been bent. So i was wondering just exactly how and what is the easiest way to do a compression check. Also if im in the wrong forum or this another post about this please point me in that direction. Thanks for any help
Staging Lane
Joined: Jul 2006
Posts: 81
Likes: 0
From: Atl. ga
How is the engine running after you replaced the bent pushrods? If it runs smooth, I would say you probably didn't bend any valves. You can buy compression gauges at pretty much any auto parts store. Take each spark plug out, remove the fuel pump fuse. Thread the tester gauge in the plug hole and crank engine over to get the reading. Repeat this on each cylinder. If you find one that is considerably lower, you may have bent valves. Good luck.
Just like the title says, ive been lookin through forums trying to find a post and can not find one. My car was miss shifted 2-3-2 and over revved. Bent 7 pushrods which i have replaced already but im afraid of wether or not a valve has been bent. So i was wondering just exactly how and what is the easiest way to do a compression check. Also if im in the wrong forum or this another post about this please point me in that direction. Thanks for any help
Go buy a compression check tool. It's a hose with a fitting on one end that screws into your spark plug hole & a guage on the other end.
If you have a bent valve it should be running terrible.
To answer everyones questions, after replacing the rods the motor ran great no misses and smooth as it was before. On the other note when all this happened it also messed up the internals on the tranny causing the tranny to knock, so it has been taken out and is gonna be on its way to sixspeedsinc. Thanks for all your help I will most likely go buy the tool soon and check it out while im tearing everything apart. What should average compression be at for each?
Yeah, get some really thick arm gloves to, since you won't have any skin left on your arms and fingers once you are finished. Compression checking no 8 would be lots of fun w/ a hot motor.
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Well thats why ill start with that plug first and work my way around to the easy side. Also ill have a friend there to read the guage and write down the compression so we dont have to run the car very long and try to keep it cool otherwise itd take me all day cuz it be to hot 
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i'd pull the heads... check your valves and LIFTERS! I just bent 3 pushrods, and apparentley it took out my lifters as well...
at first i just changed the pushrods out and all ran fine... but since i had a damaged lifter or two, I bent another pushrod within a few weeks... and that was baby driving....
at first i just changed the pushrods out and all ran fine... but since i had a damaged lifter or two, I bent another pushrod within a few weeks... and that was baby driving....
ok heres what im curious about this still, from my understanding you dont need to run the car you just take the plugs out and insert the guage. Then turn the motor over a few revolutions and read the gauge for each cylinder. Also to pull the fuel pump fuse to stop it from running during each check. Is this correct?
I would also do a Leak down test.. it will tell you more on any problems that you might have.. bent/leaking valves or guides, Compression Rings bad.. General health of the engine.
Compression test will only tell you the static compression, Ok.. but not much else from it.
Compression test will only tell you the static compression, Ok.. but not much else from it.
Make a chart for cylinders 1 thru 8 with 2 columns labeled: DRY and WET. Do the dry check on all 8 cylinders then do it again wet on any cylinders that test inordinately low during the dry test. Write down the dry results and compare the dry and wet readings. You can prove that the valves are the problem(if there is one) once you do the wet test. If the wet values don't go up the valves are bad on the cylinders that tested low on the dry test.