Can anyone tell me what the compression readings should be on a 1996 Johnson Ocean Runner 150HP 60deg looper? I right about 90 on all 6 cylinders. It is good that they are all close, but is 90 low?
It depends on a lot of things; You want to have the engine warm and well lubricated, and have all the spark plugs out when you do the test. You need to use a good screw-in tester. The battery needs to be fully charged so that you are cranking fast.
90psi is not low on a 60* looper. Sometimes I feel like a broken record. . ."it is the spread that matters . . .click. . .it is the spread that matters. . . it is". . .etc.
This was the first time doing this test myself and I was unsure of the procedure. I did not remove all plugs when testing - removed one at a time. Engine was cold, but battery was fresh. Would this skew the results?
