Question: What should my compression readings be on each cylinder of my yanmar diesel engine model 2gm?

(Posted by: Pinky on 2010-08-13 04:59:03)

Anyone know? anyone know a website to find this for free? this is a marine engine. thanks!

Posted by: 45 auto on 2010-08-13, 09:23:53

Here is a site that tells about the 2gm and what I found is over 200 lbs on each cylinder. U do know to turn the water off and disconnect the exhaust and check the Exhaust elbow as they plug up with carbon and lose of power black smoking. boatpoint.com.au/ print.aspx?TabID= 804587 &R= 1960607 &ModID= 1612404

Posted by: HHMM on 2010-08-13, 06:13:58

I dont know the PSI but PSI should be over 200 and all cylinders should be within 40 psi of each other

Posted by: ricsudukai on 2010-08-13, 06:20:34

Within 5 % of each other. The workshop manual will show an allowable range, and a service minimum, but it is more important that the readings be pretty close, than an absolute number.