115hp merc water pump?

[chrisausti]

I have a friend who has a 73 mercury 115hp. He is having trouble with it pumping water. He has replaced the water pump but still can't get any water to come out. Claims he has no thermostat. I am no mechanic but thought someone here might could help. He has a manual.

 

[WillyBWright]

Re: 115hp merc water pump?

He's right. No thermostat. There is a rubber gasket that fits snugly around the exhaust tube. If that is missing or leaking, exhaust pressure can overcome the pump.