One hot 76 Johson 115

[rcollicott]

Put my boat in the water today and the over heat alarm went off in just a few minutes of running. I think my water pump impeller must have gone out. Could not see anything coming out of the pee holes when I started it after it cooled off. I believe the alarm comes on before any engine damage, Right?

 

[boobie]

Re: One hot 76 Johson 115

Correct. Do a water pump job on it before you run it again.

 

[emdsapmgr]

Re: One hot 76 Johson 115

How long since you replaced the vernatherm (thermostat?)

 

[rcollicott]

Re: One hot 76 Johson 115

I have only had this boat a couple month's now. Dont know when or if it the thermostat was ever replaced but was told they are pretty bullet proof and shouldn't worry about it. Is this true? Should I go head and replace it? Do they get damaged if over heated?

 

[rcollicott]

Re: One hot 76 Johson 115

Think I replyed in the wrong place. But to tell you I don't know if the t stat has ever been replaced. Was told they are bullet proof and didn't need to worry about it. Is that true?

 

[Coachjfk]

Re: One hot 76 Johson 115

I've had this same motor for about 5 years. Does yours have a retrofitted "pee hole"? I haven't gotten around to adding one yet, but I did change the impeller and pump as a precaution since I did not have all of the history on the motor. Get yourself a good manual. The procedure for adding the pee hole is well documented on the forums but won't be found in a book.

 

[iwombat]

Re: One hot 76 Johson 115

_I_ think vernatherms have a lower failure rate than the t-stats, but they will fail. On that motor, the problem you'll likely encounter replacing the vernatherm is not breaking the bake-o-lite housing the vernatherm sits in. It's really brittle, and the gaskets like to stick to it - use penetrating oil to try and soften everything up and don't pry.

 

[emdsapmgr]

Re: One hot 76 Johson 115

If you have an overheating issue, probably a good preventative maintenance task would be to replace the vernatherm. While you are inside the thermostat housing, you can check the other component, the pressure relief (check) valve.

 

[Solittle]

Re: One hot 76 Johson 115

I have only had this boat a couple month's now. Dont know when or if it the thermostat was ever replaced but was told they are pretty bullet proof and shouldn't worry about it. Is this true? Should I go head and replace it? Do they get damaged if over heated?

I'll bet it was the seller who told you that the thermostat was bullet proof. Do yourself a favor - get the omc service manual (not after market), replace the water pump and t-stat AND read about replacing the deflectors. Start with a compression check and go from there.

If the pee holes you mentioned are the two holes on the upper mid section on the rear you will not normally get a water flow out of them when running on muffs in the driveway. You should in the water with some power under load.