1972 johnson 50 hp...overheat question

[bluebrownie]

could someone share with me the overheat sensor process in a motor like this... i am not sure i have the proper name, but the sensor on the back of the powerhead that will make an alarm go off in my throttle control box... my motor kicked off after a while of open throttle... seems to be an overheat thing...if i sit and wait 5 minutes or so, take the cowling off, it starts right up... if the sensor goes off, or it over heats, does it cut the engine off or do you turn it off manually... just trying to figure out that if that sensor is bad, could that be leading to the motor cutting off... when i ride with the cowling off, it never cuts out... any info would be greatly appreciated.

 

[bluebrownie]

Re: 1972 johnson 50 hp...overheat question

oh, and i forgot, i NEVER hear an alarm go off...

 

[tashasdaddy]

Re: 1972 johnson 50 hp...overheat question

sensor just sounds the alarm. i had the same motor, it was a powerpack heating up and failing, next time check your spark immediately. can you hold you hand on the top of the block for a 3 count. if so it is not overheating.

 

[bluebrownie]

Re: 1972 johnson 50 hp...overheat question

tx for the info... i have been having this problem since i got this motor 1 year ago... i replaced the stator, powerpack, rectifier.....all new...still conked out...but after apparantly cooling down, rode around with the cowling off, no problem... any ideas?

 

[tashasdaddy]

Re: 1972 johnson 50 hp...overheat question

possible gasket leak between powerhead, an mid section, allowing it to suck exhaust up to the carbs. they don't like there own exhaust.

 

[rebmo]

Re: 1972 johnson 50 hp...overheat question

I had this same thing happen on my 72 50 Johnson. For some reason I had a gas tank that failed to provide fuel, either the pickup filter was clogged or ???? I switched to another tank I just happened to have it went away. I flushed out the other tank and it seemed to work fine after that, so I assume the filter was plugged. It could have been from gunk freed up when the fuel in WI changed to 10% ethanol (sux). I was also able to keep the engine running by pumping the bulb, but it would die when I stopped pumping it.

BTW, I had a power problem with this motor that was solved by doing a carbon burn off using sea foam. I went from 22kmph to 28kmph with much better out of the hole performance. That process really works.

Reb