6.2 diesel coolant in oil

[CUCVmike]

I got a M1009 and that had no coolant or oil pressure gauges functioning or reservoir tank when I got it. I immediately bought a reservoir tank for the radiator. I then noticed some of the coolant was missing and then a little more and a little more. I had numerous leaks fluid leaks and began fixing them. I wound up pulling the motor and going through all the seals on the motor. I couldn't find any cracks or blown head gasket with a diesel mechanic checking my work. I was nervous when he thought everything was good and told me to put her back together, not ever knowing a cause. I drove her twice about 15-20 miles round trip after getting the coolant and oil gauges fixed and adding a tach as well as a banks turbo kit which also has a exhaust temp and boost gauge. The first two times she took a little coolant and I noticed a little moisture around the two caps on the intake that are installed as part of the banks kit. Then the third time it was half a reservoir tank and the forth and fifth time we went 15-20 miles round trip it was an entire reservoir tank. I then was told to take the head off by my diesel mechanic and have them pressure checked at a local machine shop. I also took the radiator to a radiator shop. The machine shop said they tested good and showed me where to look at the block for any rough areas that could pass water from the coolant passage to the block. The radiator shop tested the oil cooler on the tank up to 25 psi. I know that the oil pressure would be 40-50 psi so I am not convinced that test was any count. Radiator shop tended to think that the machine shop didn't do a good job. The machine shop charged me $135 for pressure testing the heads. Seems like the crack would open up when the head was hot so the cold head wouldn't necessarily leak? I am at a loss for what to do next. I have access to another motor and this sick motor has a lot of coolant in the oil when you pull the oil drain plug. I just don't want to have to pull the block/turbo and reseal the other diesel that may have issues too. Please advise me what to do next. I bought new Fel-pro head bolts last time and torqued them per the instructions and marked my head and bolts for the last turns. I did purchase studs this time and I do have the older 1984 head with the extra rear coolant passage. The 6.2 fel-pro head gaskets didn't have the extra coolant passage as I was told they would and I don't have nor could find any of the plugs mentioned to buy from years ago. I went ahead and bought the ARP studs and 6.5 fel-pro head gaskets for this time, but am not comfortable putting it back together not knowing what the problem is. Yes, I cleaned everything with a razor blade, fine 1" dia. steel wheel, sand paper, and degreasers. I also didn't touch the gaskets with my hands either. Please advise me as I am grasping at straws.

 

[cpf240]

First tip: Use paragraphs - makes it much easier to read

Now, when you tore down the engine, did you pull the water pump? As I recall, there could be a place there where water can get into the block, as some of the bolts go right through some passages. Extra care is needed when installing the water pump. Don't know if that is the cause of your problem, but knowing what was done with the water pump may help others diagnose the problem.

 

[AECS]

Have the heads and block NDI tested, ie magnaflux, edy current or Xray, Xray being the best and most expensive.

 

[CUCVmike]

Sorry was in a hurry and typing away. The water pump I didn't mess with. It was in good shape as far as I could tell. May not be original.

 

[Skinny]

I would think that if the radiator didn't bleed down with 25 psi, it won't with anything higher. I could be wrong but I would think it should be ok. Maybe install a remote oil cooler temporarily to bypass the one built in the radiator.

I would pull the oil pan and pressure test the cooling system. Maybe you will be able to visually see where the coolant is infiltrating.

 

[Speddmon]

First tip: Use paragraphs - makes it much easier to read

And here all this time I thought people were just giving us a hard time about being grammer police and trying to run newbies off because they won't punctuate and use proper sentence structure and punctuation.

Apparently, proper grammer/punctuation does serve a purpose.


To the OP, I hope you get your issues fixed, this is the best resource you'll find for these vehicles.

 

[doghead]

I would go with a radiator pressure/leakdown test.

 

[markg]

I had the same problem with an 09 i picked up from ft hood several yrs ago. the truck was nice and had low miles (less than 20k) but it would eat coolant and make milk shake in the crank case. long story short is that i went through all the steps you did, and at the point i was about to give up i pulled the heads one last time. the piston in the bad cylinder happened to be down, i ran my fingers down the bore and found a hair line crack wich you could not see but could feel. i put a different motor in that truck and went on down the road.

 

[Barrman]

I concur. Pump the system up to 15 psi in a nice noise free environment. You will be able to hear air leaking.

 

[nyoffroad]

Did you do a pressure test on the coolent system BEFORE removing the heads? If so what did you see?
The water pump bolts is an idea I wouldn't have thought of, but if they leaked I think it would be at the same steady rate.

 

[Patattack]

You blown a head gasket or warped One of your heads. It can't be your cooler because oil and coolant would be mixing in the radiator and there no way it's the water pump, yes it bolts to the block but none of the bolts go throw the water passage in the pump. Look at the exhaust coming out of the back, if white is coming out more then usually, then your burning green. Take each injector out and check for coolant residue on the tips. If you still can pin point it, then pull the heads of check to see we're they failed, its usually in the back, then take a strait edge and a flashlight and check for warp edge on the heads and block. If the head is warped... Well find some good ones then. If the gasket failed then put a new gasket in. But remember to put new head bolts in because there torque to yield. Also pull your dipstick out and check for sludge at the top that's also a tall tale sign.

 

[CUCVmike]

I already had the heads and radiator out. Saturday I pulled the block out. Sunday I started to take down a 6.2 out of a m1008 with 37k miles that someone put a cummins in that I got for $250. I going to fix the rear main and put all new seals in it while it's out and put it in my m1009. I still can't find any cracks in the original block and don't trust it or the heads. I know this motor doesn't have coolant in the oil just slightly higher miles than mine had. I didn't due a leak down test before pulling the heads off and since its tore down I'll just go with this other motor. When I get it back to life I'll investigate the original block and let you all know what I find. Thanks for all the great help!

 

[ranger1950]

Was in the process of changing the coolant in my m1009 , noticed what looks to be oil in the coolant. No coolant in oil and no white smoke. Back flushed several times with clean water. Water clear until I ran the engine. After cooling down the water got dirty again. Suspect heads. Any thoughts?

 

[cucvrus]

Pressure teat the cooling system. Could just need the heads machined and the head gaskets changed. It happens that way at this point.

 

[Barrman]

Double the pressure test suggestion. Maybe it had a bad head gasket 20 years ago and residual oil is what you are dealing with. Don't make a problem until you confirm you have a problem.

 

[911joeblow]

99% of the time the heads crack around the #7 or #8 cylinders and the same goes for the head gaskets, cylinders, lower end issues etc. These engines run 50deg-60deg hotter at the back of the engine vs the front. So spend your time searching there.

When you get this fixed look at putting a cooling upgrade kit on there to balance the temps for the future.

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