Compression Test: Manually Turning Crank?
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I guess the title pretty much sums things up. Let's say you've found a long block, but want to run a compression check. Can you just manually turn the crank with a wrench to get readings?
If not, I'm going to go ahead and pull the heads off of it and tear it down without the test.
Any help would kick an *** or two
If not, I'm going to go ahead and pull the heads off of it and tear it down without the test.
Any help would kick an *** or two
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Yeah it wouldnt work. Even after an engine has sat. My engine sat for about a year or so with no oil in it when i was working on it. I first thing i did was make sure i had oil pressure when i was cranking it with the starter. I got readings from 15psi to 135psi. People said my engine was shot. I continued the build and started it up anyway and after about 3 heat cycles i did another compression check, semi warm. all were 155psi within 2psi of each other. So no, not without having an actual running and warm engine is there anyway you can take an accurate compression test. you would also need to crank it over about 4 times to get a good reading at the rate a starter does it which is like 250rpm or so which is like 4 rotations a second.