Reply To: 56 Johnson Auction Find

[jarheaddoc]

I always wonder what happened to a motor when I see a fix like that.

The low compression could be any number of things, as I’m sure you know: rings stuck from sitting, worn cylinder(s), bad head gasket, other things I can’t recall right now…. I am a big fan of SeaFoam to give an engine a good internal cleaning. I have had good luck with it when it came to unstickifying rings from motors that have set for too long. Someone here, many many moons ago, told me that a quick down and dirty test for enough compression to at least start can be determined by if the motor makes a puck-puck-puck type sound when pulled over at cranking speed. (Frank Robb’s name comes to mind.)

Don’t forget to check the coils, as original ones of that era, even if they look good, can be defective due to the plastic covering.