18hp johnson temperature

[thbtgold1]

I am not sure what the running temperature is on my 1958 johnson 18hp o/b. I have completely rebuilt it, but had some problems with the H2O pump. Also does anyone know if I can use a "temp-stick" on top of the thermostat?

Thanks,

Tom

 

[boobie]

Re: 18hp johnson temperature

Go to Harbor Freight and buy a temp gun and then check it. The sticks are a thing of the past. They were never that acurate anyway as I have used them yrs ago.

 

[HighTrim]

Re: 18hp johnson temperature

Can you give us some more info? What problems exactly are you having with the water pump? Is there a steady stream of water from the exhaust port?

Can you hold your hand on the head for a 1, 2, 3 count? If water sizzles when you splash it on the head she is too hot.

How deep do you have the motor submerged? The water line should be a couple inches below the exhaust port.

 

[Bob_VT]

Re: 18hp johnson temperature

I too use the scientific method of holding my hand on the motor for a 3 count.

 

[64osby]

Re: 18hp johnson temperature

Does the 58 - 18hp even have a thermostat? I don't think my 57 has one.

 

[Chinewalker]

Re: 18hp johnson temperature

No, 1958 does not have a thermostat. Motor temp should be warm, not hot, to the touch, unless you're running in a volcanic lake, then I suppose it might get hot...

 

[kfa4303]

Re: 18hp johnson temperature

I too use the scientific method of holding my hand on the motor for a 3 count.

+1. The exhaust water should be coming out about the same temp as cup a' tea. Make sure the lower end is well submerged in a test tank as well. You can't use muffs on these old vintage motors.

Here's a handy link too.

Maintaining Johnson E & FD Serie

Btw, I loooooove the way the '58 OMC motors look. Any pics?