72 65hp johnson cuts out

[dumbboatguy]

I have a 1972 65 hp johnson that i took out on the water last week. It starts up no problem. But taking off, the engine cuts out. It will do it all the way through full throttle. It will cut out but then come back and sometimes eventually it will go wide open only to cut out a second later. It doesnt seem to cut out at say less then 1/4 throttle. Sometimes it even cuts out enough for the engine to die out. Brought it home hooked up hose and checked for spark which all 3 had. Did compression check and one was alittle lower then the other two which were identical. Next tried grounding out each plug while running and the one that didnt effect the running of the motor was the one that had alittle lower compression. Please Help!

 

[tashasdaddy]

Re: 72 65hp johnson cuts out

read carb cleaning and adjusting in the TOP SECRET FILE > http://forums.iboats.com/showthread.php?t=299680

 

[dumbboatguy]

Re: 72 65hp johnson cuts out

Brought boat in finally and they said the thermosta was bad and the syncronized the carbs. Took it out and it still does the same. Brought it home and decarded it with seafoam. Then tried it out again and still the same result. So they pretty much charged me 250 to change the thermostat. Any other ideas?

 

[tashasdaddy]

Re: 72 65hp johnson cuts out

check your timing, it has to be pretty precise on those motors.