checking compression

[44sparky]

what is the proper procedure for checking compression on a rope start(rewind) older outboard? car engines require a wide open throttle to get the highest reading, as well several strokes are necessary, each one higher than the last. true of outboards??

 

[S.T. Marine]

Re: checking compression

Take all the plugs out. Attach the comperssion tester. Pull the motor over several times untill you get your higest reading. Do it to all of the cylinders. ITs very easy.

 

[44sparky]

Re: checking compression

thanks for the advise but still wondering whether having the throttle open when checking compression would give a higher reading. taking in a full charge of air would seem to indicate a higher reading. thanks.

 

[S.T. Marine]

Re: checking compression

Nope has nothing to do with it. Compression reads in the cylinders not out of them.

 

[44sparky]

Re: checking compression

yeah, i guess 2-strokes are different, i know on 4-strokes, they recommend open thottle plates for compression check. thanks again.

 

[S.T. Marine]

Re: checking compression

Any time...