I am looking at purchasing an 1984 johnson commercial 40hp. My concern is the compression it shows 112 psi and 110 psi. It seems too low. What do you all think?
Welcome!!<br /><br />A lot depends on the gauge and what head is on it. The commercial heads sometimes have more cc's than recreational heads. If its been sitting and the cylinders are dry -- that will have an effect too. Also a good decarb may improve the numbers some.<br /><br />The compression is even. Overall I'd say it was pretty good so far.
