1986 Evinrude 40hp temp alarm goes off

[digger658]

First post and first boat in a very long time.

Just bought a SeaArk with the above motor. Sunday took it out on the river and trolled (opened it up a couple times) about 3 miles then stopped to fish for about 1 hour using the trolling motor.

Started the motor and at idle speed went for about 100 yards and the high temp alarm sounded. shut the motor off for about 5 minutes and restarted it. At idle speed again went about 50 yards and the alarm goes off again. We set for 5 minutes started again and I went to 1/4 thottle and the way back to the ramp with no alarm.

Always had good solid stream of water coming out of the tell tale. Took the cowling off and felt the top cylinder (second time the alarm went off) and it was pretty warm to the touch, don't want to leave my hand on it for very long.

Where would you start to troubleshoot this problem? I did ground out the sensor with the key on and the alarm sounded.

Thanks for the help.

 

[Silvertip]

Re: 1986 Evinrude 40hp temp alarm goes off

A thermostat that is stuck closed will likely set off the alarm at slow speeds. A stuck bypass valve will set off the alarm at high speeds. If either is stuck open, it won't overheat but it may run funny because it is not coming up to proper operating temp.

 

[digger658]

Re: 1986 Evinrude 40hp temp alarm goes off

Silvertip you my just be right about the lower speed. When I run full thottle would that help force water into the intake and up into the motor to help cool it? Also, wouldn't a stuck close thermosat regulate how much water comes out the tell tale?

 

[EN2]

Re: 1986 Evinrude 40hp temp alarm goes off

The water that comes out of the tell tale,is plumbed to exit before the water is pumped to the engine.

 

[digger658]

Re: 1986 Evinrude 40hp temp alarm goes off

The water that comes out of the tell tale,is plumbed to exit before the water is pumped to the engine.

I think I'm going to put a new water pump and thermostat. Is the water pump a 2 man job as I have read?

 

[geoffwga1]

Re: 1986 Evinrude 40hp temp alarm goes off

So what you're saying here is that water coming out of the telltasle is no indication that water is going through the motor,right.
Geoffwga1.