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b94 Johnson 40 hp cuts out at high speeds

cs01ba

New member
"I've had this since new a

"I've had this since new and rarely used but always winterized. Starts and idles fine, but power would cut back at high speed, then engine would quit. Would start back up but had no power and would quit again then wouldn't start until a few hours later (heat problem?) Managed to get it to a marina. Top spark plug was loose, but was also chared grey and dry. Bottom way black and oily. Upon compression check, top was 130 and bottom was 150 psi. Mechanic then said the engine was on frits as top cylinder would need rebuild. Alarm has been sounding sporatically, but goes away after restarting. Any suggestions? Things I can check to provide more info? Mechanic said job would be $1500!!! and I shouldn't use it anymore."
 
"If that compression reading i

"If that compression reading is accurate, there is a psi reading difference of 20 psi between the lowest and highest reading... Not Good! Your mechanic is telling it like it is UNLESS the head gasket is faulty.

I'd suggest that you remove the cylinder head in order to inspect that head gasket first."
 
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