how to check water pump/t-stat

[Sarge]

I have a 1979 85HP johnson. how do I check to see if the water pump or thermostat are working properly. engine seems to run ok. I notice that there used to be a small stream/jet of water from bottom of motor/power head but it is not there now. I don't know what it is called sorry. I am mechanically inclined, just don't know much about boat motors. first one.
thanks in advance.

[Sarge]

anyone??

[RUSTY63]

Sorry you haven't been answered yet but lets see if I can help.

The small stream of water is called the overboard discharge, it may be plugged, dirt dobbers, a form of wasp, like to make nests in this tube, use a small stiff wire to poke in the tube to see if you can clear the debris.

To check the thermostats you will need some way of checking cylinder head temperature, you can get a hand held temp gun at most auto parts stores for around 40 bucks, start the motor with water attached via garden hose on in the lake, run motor at idle, BE Carefull, the motor cover is a machinery guard and Flywheels Eat flesh, when the motor is at operating temp, the cylinder heads should be at 140 to 160 degrees, you can use the temp gun to watch the temp climb and fall, this will show you the thermostats are working as is the water pump.

If you have not had the water pump replaced in 3 to 5 years, fresh water, you should have it replaced.

Hope this helps.

[wecker20]

1st thing I'd do is replace the water pump. You'll have to drop the lower until but that's about all I can help w/. Don't run the motor until you do. No water = upset motor.

[wecker20]

[Sarge]

Thanks guys, I think I will replace the pimp just to be safe. I have no idea when it was replaced before.
thanks again


I meant I will replace the pump.


Modified by sarge at 4:06 PM 5/21/2005