engine temperature

[Denny]

Has anyone had this happen before?  I live aboard and run my engine a lot.  About once a year I have a change in engine temperature that lasts for about a month to six weeks.  My engine temp usually runs at 162 but during this period it floats between 170 and 180.  It may run at 180 for a few minutes and then drop back to 170 in say 10 seconds, then back to 180 a half hr later, etc, etc.  After a month or so the whole thing clears up and runs at 162 again.  I have cleaned the heat exchanger, added new antifreeze, had the whole impeller rebuilt for another reason because it leaked.  Nothing seems to clog the exchanger like broken fins from the impeller.  The whole problem seems to have a mind of its own.  I have the Universal M-25, 21 hp, 1986 #142 hull.  Right now the "wild thing" is behaving great at 162??????  Any similar experiences?
Denny #142 Turning Point

Denny

[tandm]

A wild guess but have you change the thermostat yet?

td
Peregrine #543

[Denny]

Thanks guys for the info.  I have treated myself to a new expensive Universal thermostat but have it in the ready position, meaning engine parts drawer.  I guess I am operating dangerously "if it isn't broke don't fix it yet"  I do have an extended stay coming up in July so that will be the time.  Thanks for all your help.
Denny

Denny

[rwilkinsii]

I would like to know what the temp should be on the m25; when i am running it for extended time it doesn't seem to go above 130 and there is a thermostat in it.

Rich Wilkins
Houston Tx
86 c34
S/V Lil Tiger
Geaux Tigers!!

[rwilkinsii]

Ron, Is this something i should worry about? or just leave well enough alone?

Thanks for the help

Rich Wilkins
Houston Tx
86 c34
S/V Lil Tiger
Geaux Tigers!!

[Stu Jackson]

Running Cool

...is not good for diesel engines.  Rich, it's not something to worry about, it IS something to take care of.  It could be something as simple as a new thermostat.

Stu

[rwilkinsii]

Should I get a higher temp thermostat? If so what should I get.. This weekend is project weekend for what ever shows up. Main thing is the alt brkt and stuffing box and wiring a plug under the setee for the battery charger.

Rich Wilkins
Houston Tx
86 c34
S/V Lil Tiger
Geaux Tigers!!

[rwilkinsii]

Thanks Ron.. I will get one today as it is my shopping day for the boat.

Rich Wilkins
Houston Tx
86 c34
S/V Lil Tiger
Geaux Tigers!!