1992 Evinrude 115 overheating

[jembar]

I'm having overheat issues with my 1992 Evinrude 115 at high RPMs, 4500 and over. Seems to run fine till it gets to 4500 rpms. Water coming out of the pee hole is cold when alarm comes on. When I disconnect temp sensor on starboard side alarm stays on. Disconnect port side temp sensor and alarm goes off. So the issue seems to be on the port side. I have checked the thermostats and the poppets and they check out good. Also changed the water pump and have around 16 psi at 4500 rpms. Need help in what to try next.
Thanks
Jembar

 

[oldboat1]

Have you checked the tops of the heads to see if there is overheating? Too hot to touch? Or with IR sensor, 160F.

 

[jembar]

yes. differently too hot to keep your finger on and checked it with IR sensor and it was reading 190 when the alarm sounded. Also, the alarm went off fairly quickly and I was able to run back to the ramp at 3500 rpm.

 

[jembar]

This is what I found when I removed the port side head. The middle water deflector created a blockage in water flow. I'll be replacing the deflectors on both sides just to be on the safe side.

 

[boobie]

Let us know what happens when you get it back together.

 

[boobie]

Did you ever get it fixed ??

 

[ct1762@gmail.com]

isn't the purpose of a deflector to "block" water flow and redirect it through the heads? am i missing something?

 

[jembar]

Okay so I installed the new water deflectors and sealed everything up. Now it's over heating at idle and the pee stream was steaming before the alarm went off. So I'm still over heating but it's different than the original issue. Also, the RPMs are higher at idle that before. Would run around 1000 to 1200 cold and 800 when warmed up on muffs. Now it's running 1200 cold and goes up as it gets hot, 1500. Never had this happen before. Any help would be appreciated.

 

[jembar]

Also the springs for the poppets were a half inch shorter than the originals and the air gap hole in the thermostat valve body was enlarged to 1/8".
Just wanted to make sure you guys had all the info.

 

[racerone]

The deflectors GUIDE the water around for proper cooling.----Water does NOT go through those rubber tubes.

 

[tblshur]

if yours has a rubber hose coming out the bottom of head remove one at a time if you have iots of water flow then your theromostats faulty blocked or something just my thoughts hope you get it fixed

 

[jembar]

Thanks for the info on the hoses. That was mu next step. I ended up taking it to the local pond and idled it at the ramp and it ran perfect. It seems that since everything was cleaned out and the deflectors were replaced, I wasn't getting enough water from the hose/muffs to cool the motor. I know that's strange but that's what happened. I still need to take it out and run it hard to tell for sure if it's fixed . I'll post when I get the chance to get out.

 

[oldboat1]

Sounds like progress. Comment is a little late to the party, but when you say everything was cleaned out, do you mean you scraped around the cylinders. It looks like there is a pretty substantial build up.

 

[jembar]

Sounds like progress. Comment is a little late to the party, but when you say everything was cleaned out, do you mean you scraped around the cylinders. It looks like there is a pretty substantial build up.

Yep. Scraped around cylinders and heads and thermostat housing and associated thermostat parts. Just took it out for a hard run and it ran like new. Temp was the same at idle as it was at 5300 rpms. Ran at 5300 rpms for about 5 minutes and and was good. Water pressure was 18 psi before clean out and water deflector replacement and is now running at 13 psi at same rpms. Here's a pictures of the starboard side, which was just as bad, after I cleaned them up and installed new water deflectors..

 

[oldboat1]

looks good!