Overheating Evinrude 4.5 1980

[Murray C]

I have a 1980 Evinrude 4.5 mod ER5CSS that overheats. I took off the gearcase and found the impeller is ok. I was careful to reconnect the little drive pin on the drive shaft and reconect the tube from the power head to the pump on re-assembly. Still no water comes out the vent below the power head.

 

[Murray C]

Re: Overheating Evinrude 4.5 1980

Is there a thermostat in this engine? could it be the problem?<br />Murray

 

[Paul Moir]

Re: Overheating Evinrude 4.5 1980

Blow up the copper waterpump tube to check for restrictions. Attaching some flexible tubing to the copper line makes this a little more appealing. If it's blocked, try forcing it by attaching that little tube to an old garden hose, and blowing it out with street pressure. Failing that, you'll probably need to remove the exhaust cover and head to get at the water passages to unclog them manually. There's a number tiny water passages that get blocked pretty easily.<br /><br />EDIT: No thermostat. And the good stuff Solittle posted below.

 

[Solittle]

Re: Overheating Evinrude 4.5 1980

Murray - Do you have the motor submerged below the top of the water pump?<br /><br /><br />Best to replace the complete water pump whether you think it needs it or not. Often they will look OK but not pump well.

 

[Chinewalker]

Re: Overheating Evinrude 4.5 1980

The passages in the powerhead on those tiny twins are quite small and easily plugged with sand, silt, corrosion, etc. If you can't blow through with the compressed air, pull the head and exhaust cover and clean it out...<br />- Scott

 

[Murray C]

Re: Overheating Evinrude 4.5 1980

REPORT<br />Water pump works fine.<br />Hooked up plastic tube to water feed pipe going up to engine. Complete blockage! Took off exhaust cover plate. Poked around with a wire and found hole in the water passages going down. Eventually extracted a piece of wood just small enough to get through the screen. Clear now. Hope there is not more inside the passages. A new gasket and I will probably be back in business. Thanks to all who offered advice. Murray