Strange waterpump problem

[Skippy123]

Greetings, longtime reader 1st time poster. Ok, I am working on a 1991 Force 50HP (Model #508F91A) that has a good waterpump and key (just re-inspected) but has no water coming out of the tattle tail and is overheating. I have re-verified my alignment of the water tube during installation and have installed a new thermostat and checked the lower unit for any blockages via the screen (nasty mud dawbbers). Initially I ran the motor with the thermostat cover off to see what my flow was and seems minimal, would not pee unless I put my thumb over the thermostat hole and give the water enough time to rise. Ok, perhaps a blockage. I flushed the motor with the lower unit off from the hole where the tattle tail fitting was attached to the motor and got flow thru the exaust and the water tube. No water on the spark plugs so I don't suspect the head gasket. Runs great other than that. Any theories or ideas to try? Thanks, Skippy 123

 

[Matthew A.]

Re: Strange waterpump problem

It could be there is blockage within the powerhead somewhere. Recently a used powerhead I picked up on eBay had passages within the powerhead that were packed with particles of sand. I am not familiar with your particular powerhead. However, there maybe a pressure relief spring/valve located on the powerhead block that you may wish to remove for inspection for possible obstructions. You may also be able to attach a hose fitting where the plug is used on the pressure relief valve since many times this plug is threaded for IPS 1/2". Doing so may enable you to flush the block of debris. Whenever you flush a motor via garden hose, be careful that you do not accidently allow too much water pressure. The gaskets and seals are not designed to withstand a lot water pressure [20 psi or so] as is common on garden hose connections which maybe as high as 150 psi.

 

[bowhuntrrl]

Re: Strange waterpump problem

I just bought a boat with a Force 50 hp on it. I was told it's a '92 but can't verify the year because the serial number tag is missing. Anyways, i went to check the thermostat and it's missing. So looking at the parts breakdown while ordering a thermostat, I discovered that there is a rubber washer that sits under the thermostat, and a spring that sits behind it. This makes it function as a poppet valve. Does yours have all three parts under the cover ?? This would adversely affect watering ability if missing the spring and rubber seal.