Does anyone here know the symptoms of a failing oil cooler? In this case, it would be on a Yanmar 3JH3e diesel.
Oil Cooler Failure?
- Thread starter Kings Gambit
- Start date
I think (may not remember correctly?) that the engine oil cooler on that Yanmar is at the base of the oil filter and is cooled with engine coolant.. so should be coolant on one side and oil on the other.. Usually oil is at a good bit more pressure (when engine is running) than the coolant so engine oil-to-coolant would one failure path.. both sides are (should be) non-corrosive so the failure would most likely be mechanical, like a defect at a tube connection (welded or brazed) usually you'd see a loss of engine oil level and oily coolant in the expansion bottle. (oily coolant bottle could be several other things as well) .. another kind of failure would be fouling of the coolant side from bad antifreeze that would be overheating with no loss of oil.
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On my 50 hp Volvo Penta, Model A had an Oil Cooler, Model B has no cooler. My MD22L-B had no other change to Engine Cooling. I suspect they found that the Oil Cooler was worthless when compared to just engine cooling alone.
That is not an answer , but my 16hp Yanmar Genset has no oil cooler either.
If no engine overheat or as @kloudie1 noted, then I would not worry to much.
Jim...
That is not an answer , but my 16hp Yanmar Genset has no oil cooler either.
If no engine overheat or as @kloudie1 noted, then I would not worry to much.
Jim...
The 3JH2 does have an oil cooler, at least according to the manual, but at least one manual for the 3JH3 does not show an oil cooler. On the 3JH2, the oil cooler is located at the aft end of the engine above the bell housing for the transmission. In the 3JH3 manual it looks like there is a place for an oil cooler, but it isn't listed in the drawing. (https://www.yanmarshop.com/Media/De.../3JH3E 4JH3E Owners Manual (49961-302780).pdf)
Check the oil, either on the dipstick or draw some out with a pump. If coolant is getting into the oil it will be milky and light brown. If oil is entering the coolant, the oil levels should be dropping.
Check the oil, either on the dipstick or draw some out with a pump. If coolant is getting into the oil it will be milky and light brown. If oil is entering the coolant, the oil levels should be dropping.
Is it possible that this is a transmission oil cooler? Some engines have both. Failure symptoms would be the same though, oil in the coolant or more unlikely coolant in the oil, as the oil system has a higher pressure than the coolant system.
if you have even one overheat alarm on theses Yans, check the oil cooler feed tube which can deform from heat then start to slowly leak coolant. so the oil temp gets higher and the coolant level gets lower. carry some silicon tape to do a temporary repair, because these cheap tubes are a long wait to order from yan mar and are different sized inlet and outlet so hard to jerry rig.