Johnson 20 hp seems hot, actually has steam.

[Bearcamp]

Have a 1971 Johnson 20 hp with new thermostat and water pump. Had it out today and running at full throttle for 5 minutes the water felt hot and had some steam with it. But when I idled down it cooled real quick. Is it normal to run like this? The water wasn't that hot you couldn't touch it but I just thought it felt hotter than normal. You could hold your hand in it.

 

[fireman57]

Re: Johnson 20 hp seems hot, actually has steam.

You may have a partial restriction in the cooling system. Your water should not have steam in it. Do you have a telltale on this engine? I don't have a manual for yours but you should. If you exhaust your water out of the top of the lower unit you will have some steam and smoke with it.

 

[Bearcamp]

Re: Johnson 20 hp seems hot, actually has steam.

No telltale. It comes out above the lower unit. Pumps plenty of water. Comes out in a spray above the lower unit and below the motor cradle.

 

[REELSPORT]

Re: Johnson 20 hp seems hot, actually has steam.

check the intake screens on the side of the motor where the muffs go and make sure they are not stopped up.

 

[Bearcamp]

Re: Johnson 20 hp seems hot, actually has steam.

I didn't think about the intake screens, but I'll check.Isn't there a wax stick you put on the motor to see if they're runnin too hot? And like I said, I really don't know if it is runnin hot.

 

[Bearcamp]

Re: Johnson 20 hp seems hot, actually has steam.

I guess the bottom line is, How do I know if it's runnin too hot? Or is what it's doing normal? How do I find out for sure before I do damage? Who really knows?

 

[Solittle]

Re: Johnson 20 hp seems hot, actually has steam.

Get some temperature sticks from your dealer.