Re: Motor too low causes backed up exhaust?

[johnyrude200]

I agree with everyone.

Fleetwin, you are correct. Neutral it’s pumps plenty, anything much above high idle in gear, water starts to get sporadic, than stops. Shift into neutral and voila, water pumping is restored. If the water supply stops again I’ll look at that shift rod seal. That would be pretty annoying if that is all it was.

Chris P – I use test props on anything over 8hp otherwise I’ll get soaked…fast!

FrankR – this does have gaskets on the water pump plate.

Good thing this motor has an overheat alarm on it. I was running it the first time at WOT in my 275 gallon test tank with a test prop (wearing ear protection), and that alarm sounded. Shut it down in time to prevent damage, but it had climbed up to 210° in a matter of seconds! Shut it down, started back up with water pumping, temps dropped back to norm quickly.

I tore the exhaust cover off and didn’t really see anything that indicated exhaust making it into the water inlet to stop water flow with this 2nd 35hp motor (which coincidentally is an ’81). The stainless steel baffle appears OK. I am going to button up the motor tonight with new gaskets to be safe (originals seemed to be just fine, peeled off in one piece and were still pliable/strong), run it in the test tank, and if it overheats/stops water flow again, mount it on my boat tomorrow and try it on the river. If it overheats again, well then we know its a faulty seal in the impeller housing or something related to that.

This is my first short shaft 35 I’ve run in a test tank, but I have run into overheat problems due to air bubbles getting into the water inlet at the gearcase with motors as small as 3hp. With the smaller ones, I usually just turn the motor to get the water swirling and the cooling system keeps up fine at WOT.

I will say it’s getting old lugging a 135lb motor everytime I have to tear it down…I’ll be installing a winch system soon…a lot more of these motors to work on this off-season for next year!