Compression Check

[50 Coupe]

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.)

 

[Red63440]

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.

 

[69 Sleeper Bee]

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.

 

[50 Coupe]

OK, thanks for the info!

 

[bobsgtx]

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.