Hello to all, I have a 2010 pete 386 with a cm871. I just bought this truck and changed out the oil and after 4k miles I was getting an alarm for low oil pressure. I changed the sensor and problem was still there. I changed the oil filter and pressure went back to normal 30-40 psi. 7K miles later same problem. I have a real good non visible coolant leak (1 gallon per 1k) and i'm afraid coolant is leaking into the oil. I just changed the oil and im waiting for the results of my sample. Any idea where I should start? oil cooler? Egr cooler? Thank you!
If you have coolant intrusion in the oil, knock a hole in the bottom of the oil filter, and see if coolant comes out.
this is what happened to mine when my oil cooler was leaking.
For the coolant loss, pressure up the cooling system, with a coolant pressure test kit. I found the one i have at harbor freight. Open the flange behind the erg cooler, and look for coolant.
you can also remove you crankcase filter, this filter is a tattle tail if coolant is present in your crankcase, this filter is located on the left side of your engine block to the front of your ECM.
if oil sample is good. pressurizes the cooling system unbolt the flex pipe at the end of egr cooler and check for coolant. orther thing to check is ur transmission oil maybe bad transmission oil cooler
It could be the headgasket blown putting pressure into the coolant system and pushing it out. The air compressor could be pressurizing coolant system and pushing the coolant out. I would check egr cooler first, being the most likely suspect.
Thanks for all the suggestions I'm at a standstill until the sample comes back. Thanks all!
If it is a measurable amount it would show up on dipstick
Being above full mark . ?
How many miles has this engine done? Im no CM871 expert but many moons ago i had an M11 do the exact same apart from the rapid coolant loss. It would shut down due to no oil pressure randomly, change oil and it'd go for a while and then start to shut down randomly again. Pulled the sump off and found the big ends and main bearings were worn and causing the low oil pressure. This was at about 600000 kilometers. Then at about 800000 it started randomly running rough. This was the cam hardening coming off and then we found the head gasket had gone as well while we had her apart
I have seen bubbles on the dipstick but never above full mark. Truck has 660 thousand miles on it now. Still waiting on sample from Polaris.