waterpump problem pls help!

[john888]

I am currently working on a 35hp 1978 evinrude motor and can't seem to get water pumping out of motor. I have replaced old impeller and also installed a new thermostat. After doing this the engine is still overheating and is not pumping water. I have connected hose to pipe and water comes flowing out of thermostat so i take it there is nothing blocked up there. I'm just totally out of answers to where the problem could be. Any heads up to what i could try to rectify this problem would be greatly appreciated.

 

[Joe Reeves]

Re: waterpump problem pls help!

If you didn't replace the complete water pump, therein may lie your problem. A scoring of the water pump plate or housing is enough to create a air pocket. Also.... did you seal the water pump so that it cannot draw air between the housing and plate, or plate and lower unit?

The water level must be a few inches above the joining surfaces of the lower unit to the long exhaust housing when in a barrel or at idle on a boat. Is it? If on a boat, the cavitation plate must be approximately 3/4" below the bottom of the boat at the transom. Is it?

Check to make sure that the water tube(s) have not been inserted into the water pump grommets incorrectly which would fold the grommet over, effectively creating a shut off valve scenario.

 

[john888]

Re: waterpump problem pls help!

Thanks Joe after using your information provide i have been able to get the motor running without it overheating. Pumps water fine now.

 

[Randybeall]

Re: waterpump problem pls help!

Please elaborate. Joe's information covered the entire water pump system. What was the problem you had so that future first timers might not make the same mistake. Glad you found it!

 

[Joe Reeves]

Re: waterpump problem pls help!

John..... Yes, please do let us know exactly what the problem was.