1958 Johnson 35 water pump path

[fphowel]

Does anyone know the path, the water takes from the water tubes, up through the heads? I found the thermostat on top and wonder where the water is suppose to come out from. Is it from beneath the thermostat or the hole to the right of it that goes down the side of the power head?
I put in a new impeller in the water pump, but unsure if operating correctly.

 

[F_R]

Re: 1958 Johnson 35 water pump path

When the thermostat is closed, the water pressure overcomes the spring and valve below it and returns to the water pump and is then recirculated till it gets warm enough to open the 'stat. Once the 'stat is open, the hot water goes up through it and down thru the head and is discharged. At the same time, when the 'stat is open, the spring and valve prevents recirculation from occuring, so the water pump takes in fresh cold water from the lake. The 'stat continually opens and closes as required to maintain the operating temp.

 

[fphowel]

Re: 1958 Johnson 35 water pump path

Could I put in some compressed air into the water tubes where it connects to the water pump to see if it has an unobstructed path? That is with the thermostat out.

 

[F_R]

Re: 1958 Johnson 35 water pump path

Sure, why not. Or connect a water hose to it.

While you are messing with that thermostat, be aware that it won't pump correctly if you take the pressure valve out.

 

[justdaddy]

Re: 1958 Johnson 35 water pump path

new to iboats...love it so far....been working on a 1958 supersea horse....just a question.....what is the op temp for the stat??

 

[lindy46]

Re: 1958 Johnson 35 water pump path

new to iboats...love it so far....been working on a 1958 supersea horse....just a question.....what is the op temp for the stat??

You should start a new thread with your questions. I believe that thermostat opens between 140-150 degrees F.