Oil temperature. Something new to worry about?

[VicS]

"The engine" doesn't exist, much less have a duff thermostat. He's addressing what he regards as inconsistencies in received wisdom.

??? surely the thread is about the Perkins 4108 in the OP's boat and the fact that he has noted that the oil temperature, determined by feeling the oil filter, is unexpectedly low.

The thermostat may be faulty but the OP has not commented on the temperature of the engine itself and the circulating coolant. If the engine temperature is low then by all means check the thermostat but I suspect the oil temperature may be low because the oil cooler is using raw water rather than engine coolant. The oil cooler may be completely unnecessary and could be bypassed / removed

The arguments about TBN are irrelevant cobblers as far as the original question is concerned.

 

[RichardS]

The arguments about TBN are irrelevant cobblers as far as the original question is concerned.

Well I thought Vyv had raised a relevant and interesting matter. It just shows that you can't please everyone.

As far as the original question is concerned .... that was answered in post #2.

Richard

 

[CalicoJack]

No there are two separate systems. One the heat exchanger which cools the antifreeze with sea water. Two an oil cooler cooled by sea water as well.

 

[CalicoJack]

The engine runs at 80 degrees centigrade and warms up quite quickly. If you open the the pressure cap on the heat exchanger you can see when the thermostat opens because the water starts to circulate.

 

[lw395]

No there are two separate systems. One the heat exchanger which cools the antifreeze with sea water. Two an oil cooler cooled by sea water as well.

Lots of engines have oil cooler thermostats. you could consider that, or just give it a bit more stick, or not worry about it. Do you often find you use the engine and the oil doesn't warm up, or was it unusual?
Is this an issue that's going to devalue the engine in the timescale you care about?

 

[CalicoJack]

Yes 4108’s are supposed to be able to rev to 3500rpm, but no one has ever been able to stand the noise for more than a few minutes. As I said originally, I hadn’t been worried, in fact I hadn’t given it much thought, but I had wondered whether the oil, even though it’s just mineral, ever came up to full working temperature. I do remember, now I put my mind to it, years ago visiting Lancing Marine in Shoreham and seeing them stripping oil coolers off these engines. With regards to whether it’s usual, I can only say that every time I have put my hand on the oil cooler I have thought how cool it was.