D6C running hot

[chickenminer]

I have a D6C ( ser#10K7399) has been running fine. Usually the temp gauge barely gets into the green. Went to use it a couple days ago and after running it for 30 mins noticed it was running hot.
I shut it down and let it cool off overnight. Next morning I took the radiator cap off to add coolant, noticed a little oil film on the cap. Added a gallon of
coolant to fill it. Started it up and within 15 minutes it was getting hot again! This time when I shut it down I had some watery oil spurting out the overflow tube.

So ... I am assuming I have a bad oil cooler and that is how oil is getting into radiator?! No water in crankcase.

But... would the oil cooler cause the overheating so fast ? I'm going to get a new thermostat for it and also wondering if the water pump went to hell ?

Any thoughts ?

 

[Dave Neubert]

Start it up with the cap off cold and watch as it is started see if you have any bubbles show up if so you got a cracked head or head gasket

 

[chickenminer]

No bubbles when I checked. Don't think it's cracked head or head gasket.
Any way to tell if the oil is coming from the engine oil cooler or the Torque converter oil cooler ?

 

[Dave Neubert]

if coming from engine cooler it should be black sludge in radiator you have to pull both to get to engine cooler so just have both checked

 

[chickenminer]

Okay thanks! It's not black, tan colored, so I suspect it's the torque converter cooler.
We'll see when I get them pulled.

 

[chickenminer]

What a mess this D6 is turning into! I got new oil coolers for this machine and in draining the radiator man there was a LOT of oil in the radiator/cooling system!
I'm going to need to flush this out several times and wondering what is the best way to flush the oil sludge out? Any kind of additive that will help? Can I flush it with some solvent?

 

[Nige]

Cascade (non-foaming) dishwashing detergent. Throw a couple of pounds in, fill up with water, and run as long as it takes to get the engine up to full operating temperature. Drain, flush with clean water, and repeat as many times as necessary until there is no trace of oil in the water you drain after flushing. It might take a while on a badly contaminated cooling system.

 

[Mcrafty1]

Cascade (non-foaming) dishwashing detergent. Throw a couple of pounds in, fill up with water, and run as long as it takes to get the engine up to full operating temperature. Drain, flush with clean water, and repeat as many times as necessary until there is no trace of oil in the water you drain after flushing. It might take a while on a badly contaminated cooling system.

Cascade works well, however it is a corrosive be sure when you do the final flush you flush it well, it's not something you want left in your cooling system for any length of time.

 

[chickenminer]

Great! I'll give the Cascade a whirl and be sure to final flush it well.
Appreciate the tips !

 

[Nige]

Every time you drain the Cascade/water mix from the cooling system you'll need to throughly flush the system with water. Look out for any signs of oil in the flushing water as it is draining from the radiator. The slightest visible trace of oil will require a repeat of the Cascade treatment (and run the engine up to operating temperature again) then flush once more. Once you are convinced that there is no more trace of oil in the system, flush one last time with water and then fill the system with your choice of coolant.