What is ideal temp for engine?

(AndersonMC) · (AndersonMC) **Join Date: Mar 2010** 06-28-2011, 9:54 AM

What range should my temp be in?

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 06-28-2011, 10:01 AM

165 -175

(razzman) · (razzman) **Join Date: Dec 2006** 06-28-2011, 10:15 AM

Depends on the engine. The mercruiser on my last boat averaged around 170 which is ormal. My Indmar 325 averages around 180 which is normal for them.

(migs)

172-175 on my merc black scorp
162-164 on my PCM excal

(bill_airjunky) · (bill_airjunky) **Join Date: Apr 2002** 06-28-2011, 3:10 PM

Depends on the thermostat thats installed in it. Seems like 160s come from the factory a lot. Heatercraft usually bumps that up to a 170 or 180 if their heater is installed.

(cadunkle)

180-195 is where engines are most efficient and wear the cylinder walls the least. If you have a closed cooling system with heat exchanger, run a 180*. If you have open/raw water running through your block keep it 145* or whatever your engine manufacturer recommends. One of the main reasons for keeping temp lower in raw water cooled is if you boat is salt or brackish, the salt will crystallize at higher temps and build up on your coolant passages, causing issues long term.