1999 Evinrude ficht 150

Had the boat out this week for first time in 6mos. (but started every 2 wks. or so) and the overheat buzzer went off and i shut it off instantly. Waited about 10 min. and fired up with no problems and buzzer never went off again. Didnt make any long runs but enough running for it to get hot. I've had this motor since new and all the up grades were made after about 40 hrs on it and now has over 500hrs. Question is it was peeing plenty of water but the temp of the water coming out was hot to the touch then seemed to get cooler then hot sorta back and forth. Pulled the original t-stats out and put yhem in a pan of hot water at the same time and one opened up about a minute before the other and the valve on the one that took longer to open looked lopp sided compared to the other. Am i on the right track with saying they should be replaced? Thanks!

Re: 1999 Evinrude ficht 150

If you're in a hot climate the best thing to do is change the water pump impeller. When they sit, they want to set up.

Re: 1999 Evinrude ficht 150

I've pretty much been starting this motor up every couple weeks even though it hasnt seen the bay and the water pump probably has about 50hrs on it. Didnt see thermostats for a 99 Evin. 150 in the parts section here is there another site anyone can recommend to look at!

Re: 1999 Evinrude ficht 150

You may go here:
http://www.marineengine.com/parts/j...rer=Evinrude&section=Cylinder+&+Crankcase

Re: 1999 Evinrude ficht 150

Or try shop.evinrude.com.

Re: 1999 Evinrude ficht 150

Looks like 2 different thermostats listed but don't know which one. Not listing specifically for 99 model the one i pulled out is ceramic looking. This motor had allthe upgrades and want to make sure i get the right one.

Re: 1999 Evinrude ficht 150

Scroll down and look at the specs, then you will find the one you need. Stay away from the 'Sierra' type shown in the pic if that is the one you are looking for.

Re: 1999 Evinrude ficht 150

The sierra is whats in it now does the other one use a different spring or can i use the original.

Re: 1999 Evinrude ficht 150

To be sure what you have, change both spring and thermostat as one unit and use 'OEM'. In engines with the Sierra type, even used as OEM for some time, I always cut away the bottom part to increase the flow-through.