Reply To: Compression for 58 Johnson 10 hp?

[jeff-register]

With someone not putting seals on the drain / fill ports no telling what oil/fuel mix you motor has seen. Like others stated soak thu exhaust ports & use a small flat screwdriver to ,ightly push on the rings to see if they are stuck. My 58 Johnson ran very well on 75 compression & got better with proper oil/fuel mix with quality myl. I would replace the top cramkshaft seal to, my magneto looked like sprayed oil when I first got it.I used a tiny drill bit & made a hole in the seal metal 180 degrees out & used a drywall screw to get removal & grease to catch all the metal shavinge