Reply To: Advice please re purchase of 1958 7.5hp Johnson

[Don]

Like Bill says, the powerhead is suspect if it has been running on anything less than 16:1. The problem is you have no history on the engine so you just don’t know. Compression readings are one thing, but they won’t be affected much by leaner oil mixes, but the rods sure will be. You might try removing the recoil and the little inspection plate over the flywheel, then have a look at the coils. Seeing old/cracked coils may actually be a good thing, means it is a relatively low hour motor that probably has not been run on today’s leaner oil mixes.
As for the gearcase, I would definitely crack the lower drain screw. Milky or watery oil means trouble, and that shock thing is always suspect, especially on this engine that appears to have been used to dredge clams.
You mention that the engine is not in particularly great cosmetic condition, normal wear for its age. So, with all that said, I surely would not pay much for it. Needless to say, it will need all that work you mentioned to make it a reliable daily runner…