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70hp johnson compression

DOC30 I have just bought a 1978 70hp. Johnson Outboard and was trying to get info. on the compression.. What is the specifications for a compression test.. I check all three cylinders and they were from 90 to 120lbs.. Is this good compression for this motor?
The motor seems to run fine, but hasn't got alot of throttle.. After changeing the plugs I noticed that the top two are firing pretty good, they look like there fine.. The bottom one is clean as new.. I checked the firing and It's firing fine..I guess the carb maybe the problem.. What do you think?? I appreciate any help.. *** bless... DOC30
2001-07-11
J.B. Cornwell Howdy, Doc. Your compression is NOT-OK. Not only is 100# the minimum acceptable, 15# difference between high and low is minimum acceptable difference.

Until that is fixed, other issues are academic.

Good luck.
Red sky at night. . . .
JB

2001-07-11
DOC30 Hey, glad to get a reply... Thanks J.B.//
I decided to check the compression again after your reply.. I thought there for a minute I was going to try my first rebuild on a boat motor.. I wasn't real thorough with the first test I did.. On the second ti
2001-07-12
J.B. Cornwell Get your prop rehabbed at a local shop. Buy a cheap spare prop to keep on the boat. Congratulations on getting her going. That OMC triple has been one of my favorites since they were introduced.

Red Sky at night. . . . .
JB

2001-07-13

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