1989 evinrude outboard temp alarm.

[rmhbass]

Hi.
I recently purchased a boat that was sitting in a barn for a few years. The motor seems to run pretty good until I go to full throttle. After a few minutes the temp alarm goes off and the boat shuts down until it cools off. I was planning on installing a new impeller even though water is running through it. I was wondering what else may be causing the alarm to activate. I was told the motor does not have thermostat just a temp sensor. I'm new at boating and would appreciate any help.
Thanks.
Rob

 

[iwombat]

Re: 1989 evinrude outboard temp alarm.

What exactly are we working with here? I'm pretty sure that '89 - whatever has a t-stat.

 

[rmhbass]

Re: 1989 evinrude outboard temp alarm.

sorry. I forgot to mention the motor is a 25hp evinrude.
Rob.

 

[kskomro]

Re: 1989 evinrude outboard temp alarm.

I have a 1988 Johnson 25HP, almost the same motor. And I have the same problem today as you have. I took off the head to find a old rusted, not working thermostat. I will be off tommorw to buy a new one, along with new gaskets. My motor got so hot, it actually was smokeing and the wires were melting.

 

[rmhbass]

Re: 1989 evinrude outboard temp alarm.

Thanks for the info. I replaced the impeller and the thermostat is next.

 

[kskomro]

Re: 1989 evinrude outboard temp alarm.

UPDATE, I did not change thermostat, I was going flat out on lake, motor overheated and fried! I dis assembled to find part of the Theromostat lodged in the water passage, It blocked the water, and now is TOAST

 

[WTL]

Re: 1989 evinrude outboard temp alarm.

Thats awful news. I'm really sorry to hear it.

I dont know whats going on, but I had the same problem - today - with my 1986 28 horse. Its peeing a little out of the top, not so much near the midsection - but it overheats after going full throttle and the alarm goes off - it smokes some too. I'm gonna check the stat tomorow - do I need to take off the cylinder head or is it just the water jacket?