Medium and Heavy Trucks
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Thanks for asking your question. I can help you with this.
Those are heater core hoses. They run from the engine to the cab for the heater. THey can not cause coolant to enter the oil.
If you have coolant in the oil, you have either a failed water pump, cracked or leaking cylinder liner, a leaking head gasket, or a cracked head,
The best way to verify where the coolant is coming from is to drop the oil pan and pressurize the cooling system. You will see where the coolant is coming from.
Please reply back if you need more help or have more questions. I am happy to assist.
I see. Can you take a picture of the valve and hose? There should not be a valve that allows coolant to enter the oil.
I like to drop the pan and remove and inspect s few of the rod and main bearings. If they are worn, you will see it. IF they look OK, I would try a new oil pump.
Sorry. There is not a step by step. I wish there was. You just need to remove one at a time and inspect. The Mains torque back to 190 foot pounds, then turn an additional 120 degrees. The rods torque to 52 foot pounds and then turn an additional 60 degrees.
That looks like normal wear
NO way to test oil pump. Sorry.
Hi Ryan. My name is***** a Cooling system pressure tester with the correct adapter pressurize the cooling system with the oil pan down and inspect for leaks from underneath or through the exhaust manifold ports if you see white ash deposits in the exhaust or had excessive white smoke from coolant burning in the exhaust or combustion chamber. See if it is dripping from a cylinder, the front timing cover area, etc. Let me know
The first expert has many years experience as a trainer of Cat engines at the dealer level. I was field service for my local dealer and also have many years experience. coolant in oil is cracked liner flange/head gasket/head crack or liner seals most commonly, water pump, and in rare cases an air compressor failure.
An oil cooler almost always is oil in the cooling system and radiator. So the coolant will be sludge and black in the radiator
Thanks for the update. Hopefully this is not full of block sealer to mask that problem as coolant soaked bearings start a chemical process and eventually lead to a spun bearing.
3406E /C15 engines are known for cracked liner flanges and head gasket failures . There is a procedure for the liner protrusion and spacer plate inspection for the protrusion to be within specs or the result is a head gasket failure or cracked liner flange.
Check the backside of the bearing for a part number... See if its a Cat bearing or aftermarket and if its marked STD or oversized
On the oil filter housing remove the plugs and inspect the oil bypass valves in the housing for wear, debris, or damage.
If the liner flange is cracked it will leak coolant into the oil and you would loose coolant pressure with the pressure test
using a light look for scuffing or scratch marks on the liners and bar the engine over by hand so you can inspect all cylinders.... Also using a filter cutting tool open up the oil filter and inspect for metal or debris indicating a bearing failure possibly... It is possible you started to spin a bearing... Either rod, Main or possibly a Cam bearing in the head.
You can see the plugs.... They are sealed by o rings. i recommend replacing the o rings
If in the head a bearing could have moved enough to block the oil galley
bearing material found in the oil filter will confirm a bearing failure occurring....
thanks for the pictures....That is only marks from the o rings for the tube where they have set.
There are two allen head plugs to remove on the filter housing to access the bypass valve.
Thanks for the update. I do not like the look of that last bearing on the shop rag. I see pitting and uneven wear. This can be caused by the chemical process when bearings absorb the coolant and begin washing the bearings resulting in eventually a spun bearing. I doubt the water issue fixed itself either. There is another option if the pressure test is not showing. If this is a small leak or only when things are hot and expanded at running temp a dye leak test might be the next step and then you can pressure test and look from under with a UV light.
That you could see running down the front timing cover with the pan down and system pressure tested. Not likely but possible...
hi Ryan, Sorry for the delay. I help on here in between jobs and was on the road all day today unfortunately. Those are heater core hoses and it does not make a difference. That just shuts off flow to the heater core in the summer months for colder AC in the cab.
I dont believe I do have a flow diagram but I will see if it is in the shop manual once my family is settled in.
Thanks for the update. Yes, if you did a thorough cleaning it will take a bit longer for the soot to turn the oil but it will. Keep an eye for coolant. It sounds like so fat it is looking good. Let me know
Hi Ryan, I hope you had a great weekend. I just got your response. The electrical connectors should not take that much force unless there might be a bent or damaged pin or alignment problem. Let me know how you made out.
Hi Ryan, very odd but good news. Still keep a close eye on it. Its possible the truck was sitting and some of that could have been condensation if not leaks are revealed. Please take a moment and rate my service as that is how the site credits for our time helping on the site..