This is a weird one.

Forum member "alwaysworking" came out this afternoon with a turbo for me to bolt my 16cm exhaust housing onto. We put it together, and got ready to fire it up.

Engine started up with a jump, was idling low. But it's been idling low since I bought it.

The radiator and plastic filler immediately was pumped full of thick sludgy motor oil.

Shut the motor off, and and checked engine oil. It was totally clear.

Drained radiator, cleaned it out with water, drained it again, filled with water.

Started the engine up, let it run for a few seconds, and same thing. Coolant pumped full of oil.

This time when we checked the engine oil, it was milky, not clear like it had been a few minutes earlier.

Blown head gasket, right ?

It was running just fine until I pulled the turbo. No white smoke, it would do 70 down the highway easy.

What on Earth could cause this to happen so quickly ? I'm genuinely stumped.

Guess I'll get busy pulling the head tonight, try to figure out what happened...this would be the first time I've ever replaced a head gasket, if I wind up going that route. I had always heard these engines were the very definition of reliability and ruggedness. Now I'm not so sure.

 

You must not have good luck.

Headgaskets usually just don't blow outta the blue, expecially if your not over boosting and romping on them with high egt's.

Strange

don't give up though....i know thats hard to do when you're having these problems. Maybe its good it blew now and not when you were on the road.

 

Don't pull that head too quick!, there are a couple other things to check first. Like the oil cooler.

I haven't had the need to muck with the oil cooler so I don't have first hand advice, so do some searching around this forum before you start taking things apart.

I'm sure that some others with more experience will speak up soon.

Good Day,
JP.

P.S.: Just another thought, are you sure that you reconnected the turbo oil drain to the correct spot?

JP.

 

I was just thinking the same thing..... It's odd that it would happen like that. I'd look at the heat exchanger first.

 

Where is the heat exchanger ?

Is the oil cooler built into the radiator ? I don't see lines, I'll look again. The drain tube from the turbo was never disconnected from anything but the turbo. Loosened the clamp at the bottom, tightened it back up.

Alwaysworking said that from the way it sounded, lugging a little as it started up the second time, he was almost certain it's the gasket. There is a bit of oil at the rear of the motor on the outside.

 

Well Always has blown a few of his own. He most likely knows what to look for. I thought the oil cooler ( heat exchanger ) in question was the one for auto trannys not hooked to the engine oil. I was unaware of a oil cooler for the motor.

 

I'm gonna pull the assembly the oil filter mounts to. Maybe something went wrong in there ?

 

That's where the engine oil cooler is, the thing the filter screws onto is the cover plate. The cooler sits in the water jacket on the block.

You can kind of see it on here:

 

I learn something every day.

 

How do I know if it's kaput, and can it fail suddenly, causing oil to gush into the coolant like that ?

OK, I have a hot thermos full of tea now, time to remove plate.

 

the way it sounded was like it it was sucking water, i thought about the heat exchanger/oil cooler but i dont think it would pressurize the radiator so fast.

if it is the heat exchanger thats good.
the exchanger could crack if the casting is bad, maybe since the oil was colder making higher oil pressure it could crack it?

 

I removed the plate that the oil filter screws into. It is secured by a number of 10mm bolts around the edge and one in the middle.

Looks similar to the underside of an automatic tranny. I take it this is where the oil flows around and is cooled ? I can see milky white oil burbling out of what looks like a plate underneath the top plate, but I don't know how to remove that.

Is this a thick gasket of some kind under the plate ?

Could it have failed ?

Maybe some water got down the tube that mounts to the bottom of the turbo and caused problems ? I did wash down the side of the block while the turbo was off, but I'm pretty sure no water got in there.

If it did, could that be the cause ?

Also, now I see some dripping marks at the head where it mounts to the block, but since the valve covers are now off, I don't know if that's from the contaminated oil dripping down from above or what.

So is this a gasket of some kind under the plate the oil filter mounts to ?

 

Found something interesting in the Cummins B series manual I have in PDF. Check out the images from it I attached. Describes symptoms exactly. Oh yeah, Thomas, I'm mailing this PDF to you right now. Check out section 2 page 2-11

EDIT: Shoot, the PDF is too big to email. I'll try to find where I downloaded it from.

 

can you see any cracks in the oil cooler?

 

Is there a way to pressurize oil passageways with compressed air to check cooler?