E120TLERC continious warning horn

[jimbobcooter]

I have a 94 Evinrude E120TLERC. We were out on the lake today for about 4hrs. She ran great until we went to run home. We idled out of the cove we were in and then cranked her up to about 80-90% of WOT. After about maybe 3-5min a continuous alarm sounded. My brother was driving so I told him to shut it down immediately. He came to a safe stop and shut the engine off and the horn stopped. When I put the key back in the ignition and turned it to the on position the alarm sounded continuously again. When I pulled the cover the starboard side had a tacky liquid on it b/w the two plugs (not sure if it was oil or paint from the head).

After using the trolling motor to get back to the dock (~15-20 min) I tried starting the engine again. No alarm and water from tell tale. Shut it down Retrieved the trailer from another launch (~30-45 min). Decided to let it idle for a bit at the dock before leaving. No alarm and the port head seemed to get hotter than the starboard. I let it idle for a good 5 min with no alarm. I let it continue to idle while I backed the trailer in. With still no issue I took it for a quick spin to get her up to speed. Maybe a 5 min ride with no alarm or noticeable change in performance.

I am thinking this is an overheating issue, but I would think that it would have repeated. Could it have just been some trash that was blocking the intake grate? When the alarm initially sounded we quickly raised the engine and there was nothing around the intake on the lower unit.

Note: Water pump was changed this past winter. Carb cleaning planned for this winter as I have had some coughing at idle. Oh and this debacle http://forums.iboats.com/forum/engi...weak-out-of-the-hole-evinrude-e120tlerc/page3

 

[jimbobcooter]

I finally got to the t-stats. I found that the spring on the starboard side (the hotter of the two) was bent and deformed when compared to the port side. I am going to be replacing them both...but wanted to see if that could be the cause of my overheat?

I tested the t-stats suspended in a pot and both opened (there was a small rod that extended from one end), but neither closed once the water cooled. Sometime after taking them out of the water I was able to push the rod back down. Is typical operation?

Lastly, I found a small piece of debris (3cm x 2cm) in the spring behind the diaphragm on the port/cooler side. While everything is apart I was going to drop the lower unit and run some water through the cooling system. Would it be best to flush from the bottom up or the top down or both?

Thanks for all the help!

http://tinypic.com/r/qsnmrq/9 (pic of spring)

 

[Bosunsmate]

I flush from top down then reverse it and then reverse that again.
The t stat on mine, a 1982 60hp closes by itself. That might not mean yours are abnormal especially if they are working against the waterpressure to open. So you should check that out. But they wouldnt cause the overheat, id be more inclined to blame it on the spring since that comes into play at the high speeds you mention you were at when it overheated.
Goodjob turning it off quickly. Make sure nothing is warped, t stat, t stat housing and or vermatherm/poppet valve if that motor uses those

 

[jimbobcooter]

Thanks for the flush suggestion. I might just go ahead and replace the tstats since I am there. Everything else looks good besides that spring. Could the spring have become distorted causing the overheat? Or did the overheat cause the spring to distort? Just curious if I should keep digging or if I should feel confident that the spring was the culprit?

Thanks,
Joe

 

[Bosunsmate]

Hard to say, id imagine the spring distorted first but thats one for the unsolvable files.
Id put it back together and test it out, odds a that it wont happen again and it will just end up a faint distant memory