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63 Johnson 75HP

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idozark

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"I'm back with another que

"I'm back with another question about my 1963 Johnson 75 horse. I checked the compression and have 93 to 95 psi on all 4 cylinders. Is this acceptable for this motor? I would normally think the consistency is a good sign but it does seem a bit low. Also this is a manual shift model, is it possible to add the alternator?"
 
"The compression may read high

"The compression may read higher with another gauge. If the engine runs as you would like it to run, I wouldn't be concerned about that reading. It also will vary with the speed in which it is cranked over. I assume that you have all of the plugs removed (all) when you check the compression?

1963 model..... Are you sure that it doesn't already gave a alternator?"
 
"Thanks for your response, I a

"Thanks for your response, I appreciate your help.

I did remove all the plugs to test compression.

When it is running it seems to run fine, but doesn't start if I shut it off and try to restart a few minutes later. Seems like lots of raw fuel in the intake at that point. I am putting in a carb kit tonight in hopes the float level/needle and seat is the problem.

I don't see an alternator or generator. It has the distributor magneto ignition. Would it have a stator mounted under the flywheel with this type ignition?"
 
"If it has the magneto , you w

"If it has the magneto , you will need a belt driven generator."
 
"Well thanks for the help but

"Well thanks for the help but I think this one just went to the big boatyard in the sky.

I rebuilt the carb and it fired right up, ran a couple minutes then kind of coughed and puffed out a large amount of smoke from what appeared to be the exhaust bypass hole and refused to start again. Re-checked compression, now down to about 62 psi on all cylinders, pulled head and found a large gouge in one cylinder that has obviously been there a while.

Bottom line, anyone know where I can get a reliable motor without breaking the bank?"
 
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