4HP Johnson cooling problem

[theonn]

I have a 1978 4 HP Johnson that has been overheating. I removed the water pump, it looked ok but will replace it. I hooked a water line to the water tube and got no flow through the engine. Then removed the exaust and water tube assembly the hole in the block si blocked. Is this a thermostat or a blockage I need to clear? Roger

 

[wilde1j]

Re: 4HP Johnson cooling problem

No thermostat on that one.

 

[Zeeter]

Re: 4HP Johnson cooling problem

They get clogged where the powerhead attaches to the leg. Take off the powerhead and youll see it. Its an easy fix all you need is a new gasket.

 

[pacman77]

Re: 4HP Johnson cooling problem- mine 6hp

Re: 4HP Johnson cooling problem- mine 6hp

does a 1972 6hp CR72D have a thermostat??

 

[Vic.S]

Re: 4HP Johnson cooling problem

6R72D you mean!

Yes under the cover held by three bolts on the top of the cylinder head.
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