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Compression Check

50 Coupe

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Jan 17, 2020
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Location
Indianapolis
Is it possible to check compression by hand turning the crank using a breaker bar or does it need to be spun up faster via a starter?

(My motor is on a stand and I don't have a starter yet but when I tried turning by hand I couldn't get any readings. However, the timing chain is really stretched, maybe that could be the problem. I will put the new one this weekend.)
 
I would imagine the engine needs to turn faster than possible using a breaker bar. What you see on the gauge is a culmination of several rotations.
 
You need a starter in it to spin the motor fast enough to get a proper reading. To much air bleed by to get a reading by hand turning.
 
If you are just checking condition of rings, valves and head gaskets a leak down tester would work if you have the tools. It wouldn't tell you anything about comp ratio.
 
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