I just bought a 75 Johnson 115. Runs good. Forward and reverse works. All seems good, but compression seems a little low. 90# on all cylinders. Any thoughts on this?
That engine would have had compression over 125 when new from the factory. I'd do some additional checking before I ran it very much with that compression. Esp check the top ring on each piston.
Variations in gauges, conditions and technique make a lot of difference in results. If all cylinders measure within a 10% span on an engine that runs and performs well it is most likely a healthy engine.
I would run it without any thoughts what so ever!!! Sound like it will preform very well for long time yet. JMHO! Why go into it for a few more PSI compression numbers...?
