How cool do you run?

[VanIslandGuy]

Your engine that is...

I've got a Yanmar 4jh2e, and I've never seen the engine warmer than 150-160'F, and normally 130'-140 is where it sits.

I've replaced the thermostat in May this year but no change. Can the cool waters we run in here in the Pacific NW be a reason for the engine coolant temps to be less than 180'F.

What are others in this area seeing when they motor? Especially with a fresh water cooled Yanmar.

 

[jssailem]

My Perkins at 80% runs 150-160 very steady. When I bought her she had issues. I had the fresh coolant pump fail. Had temp over the 200 level and alarm blaring before I could get into the slip. I replaced the pump, and all has been great, no more overheating. I check temps about every 45 minute of running. Check water flow. Even grab the infrared gauge occasionally to verify the engine temp gauge. Trust but verify.

 

[LeslieTroyer]

I was running in 180 at cruising speed if I pushed it it temps went up. Last winter I switched from a 2” to 3” heat exchanger and now only hit 150 when pushing it, and cruise in 130-140. I have a 160 Thermostat comming, I suspect a P.O. removed the stat because of overheating.

Les

 

[Benny17441]

Not surprising at your latitude. Here in the Gulf of Mexico during the summer the raw water temperature approaches 90F at the intake and engines run a little hotter. Diesels are heat machines and they run more efficiently when they are hot. Check your temperature after an hour of running at full throttle.

 

[Michael Davis]

they run more efficiently when they are hot.

My shop manual for Perkins 4-108 calls for a 190-200 thermostat. It was running really warm last year so I rebuilt the heat ex. and put a 180 thermostat in. This year it will run all day at 80% and stay at 180 but runs warmer if it sits at 15-1800 RPM. I'm thinking because of less raw water through the exchanger. (maybe?)

 

[VanIslandGuy]

Thanks for the replies everyone!

 

[BrianRobin]

My Perkins M30 runs no hotter then 175 all day long