1995 MercuryForce 120HP never warms up

" 1995 Mercury/Force 120HP nev

" 1995 Mercury/Force 120HP never warms up to operating temperature. Thermostat is good (opens at 130F in pot of water), spring for pressure relief is good and seal/seat for thermostat is good. Temp gauge never goes above 90F and engine head never gets above lukewarm to the touch. Did not used to be this way, temp gauge used to go to 130F like it should. Can't figure out what has changed. Problem is that engine is harder to start when it has already been run, like always starting a cold motor. Any suggestions "

Are you sure it has nothing t

Are you sure it has nothing to do with the temp. of the water? It's 40 degress F in my neck of the woods... that will keep an outboard pretty cool.

Jon

"Scott,

Does the engine see

"Scott,

Does the engine seem to have full power? Do you notice any difference in the way the engine runs now, other than what you have mentioned?

"

" Answer to above questions, w

" Answer to above questions, water temp is 75F and engine runs good at all RPMs. It just is not warming up at all. "

" Scott,

Strange problem.

" Scott,

Strange problem. Usually these engines have problems cooling, so I wonder if you should be concerned. If the head does not warm up, one thing you can say for sure is that water is flowing through the water jacket in the head freely.

The thermostat may be the problem, even though it tests okay. There should be a seal that fits into the recess in the head, and a spacer between the seal and the stat. Maybe the fit here is too loose? Also, the spacer is u-shaped, allowing a bypass which allows a little water to circulate when the stat is closed. Maybe the bypass area has become too large and is allowing the water to circulate freely at all times. I guess electrolysis in the stat region could also cause this to happen.


Tony "