3.0 operating temp

[gaj72]

Hi all. Have a question about my 2003 bayliner with 3.0 merc. Purchased this boat last summer and noticed engine temp would never get above 120- 130. Checked t-stat and sure enough it was stuck open. Replaced t-stat this spring and noticed operating temp to be 175 or maybe a needle width above. T-stat is a 160 degree( same as old). My question is is this normal operating temp for this motor? Just thought it should run a little cooler being a 160 t-stat and dont have anything to compare it to since old t stat was stuck when I bough the boat. Thanks! Gary

 

[kellmike626]

Re: 3.0 operating temp

With my 3.0 Liter Mercruiser (it's in a 2005 bayliner 175) I get a reading of 175-180 as well for temp.
I have not noticed anything out of the ordinary, so maybe you should be fine.

 

[tschmidty]

Re: 3.0 operating temp

Hmm, I have a 1988 3.0 with a 140 degree thermostat and it hasn't gotten past 150 yet. That does seem odd that you guys are running that hot. Have you double checked with an infrared temperature gun? They are relavtively inexpensive and I find it useful to check the temp directly to make sure it isn't the gauge or sender acting up.

 

[oldjeep]

Re: 3.0 operating temp

Mine always reads right around 175 degrees as well. 2005 bayliner 195 3.0L

 

[OJ_Simpson]

Re: 3.0 operating temp

My 2005 3.0 has run around 175 since the day i got it. Was even told by the marina mechanic that is where it should be. Not sure that i necessarily beleived him. I saw temp gauge moving up to around 200 earlier this year, and changed the impeller and thermostat and now back to 175. Glad to know everyone else is right around there too!

 

[Rocky_Road]

Re: 3.0 operating temp

Another 2005 3.0L that has run just a 'click' over 175...since it's birthday!

You are right in the ball park....

Happy boating!

 

[gaj72]

Re: 3.0 operating temp

Thanks guys, that puts me a little more at ease. Also forgot to add to my last post that I had my impeller changed out a couple weeks ago and didnt seem to make much difference in the engine temp.So as long as no other issues pop up I wont worry about it. Thanks again

 

[fat fanny]

Re: 3.0 operating temp

95 3.0LX running w/ the stock thermo and still hanging at 155 never moves above (when it's running!)

 

[JimS123]

Re: 3.0 operating temp

The 3.0 liter should be equipped with a 140 or a 160 degree F. thermostat, depending on the year of manufacture. Just look in the owners manual.

If it runs higher than that, the gauge or TS is defective, or there is a plug somewhere.