compression readings good?

just bought a 1970 65hp off ebay and was told it had low comp (but it had tilt/trim which i wanted) i tested it dry and cold and got 40 in 1 and 65 in 2 so i stopped and put a little oil in all 4 cyls and spun it for a while to clear the oil out retested and now have 135,145,148,135 are these good since its wet comp?

Re: compression readings good?

eschesworld said:

just bought a 1970 65hp off ebay and was told it had low comp (but it had tilt/trim which i wanted) i tested it dry and cold and got 40 in 1 and 65 in 2 so i stopped and put a little oil in all 4 cyls and spun it for a while to clear the oil out retested and now have 135,145,148,135 are these good since its wet comp?

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yep, should run fine. Rings were probably stuck a little from sitting.

Re: compression readings good?

It'll probably be hard to get an accurate compression reading until the motor's been run and fully warmed up. Also be sure to open the carbs' throttle plates fully when taking the check or it'll probably be low.

And once you get it going, give it a decarbonizing treatment using Seafoam "Deep Creep" www.seafoamsales.com , OMC "Power Tune", Berryman's "B-12", or other major outboard mfr's decarbonizing stuff. Seafoam is probably the best out there, "Deep Creep" is the spray-can version which makes it real easy to spray into the carbs.

Search this site for "Seafoam" or "Decarbonizing" and you'll find plenty of info on the topic.

Old Merc piston rings definitely hate carbon buildup!

HTH.........ed