Sudden Oil Spray After New Turbocharger Install

[billfz]

This was a sudden event, I never observed any oil spray prior to this occurrence.
Shop tells me the engine needs a rebuild!
Cummins 400 ISl, 55,000 Miles

Just picked motorhome up from repair shop after: turbocharger replaced! Drove 25 miles and noticed oil spray all over front of the toad.

Shop thinks it's the new turbo that's causing blow-by, blowing oil out of crank case vent tube. This is because the new turbo is providing more boost. I never had any oil spray before the new turbo installation even with normal turbo boost while climbing steeper grades (about 28 lbs).

Turbo Boost on the way to the shop before new turbo 25 lbs.
Turbo Boost after new turbo 25 lbs (grades not steep enough to require full boost).

Why is there oil spray now, even though boost pressure is about the same?

Could it be a problem with the new turbocharger (maybe a failed seal) forcing pressure back through the oil drain hose and over pressuring the crankcase? Or could it be something else?

Thanks, Bill

[palehorse89]

Originally Posted by billfz

This was a sudden event, I never observed any oil spray prior to this occurrence.
Shop tells me the engine needs a rebuild!
Cummins 400 ISl, 55,000 Miles

Just picked motorhome up from repair shop after: turbocharger replaced! Drove 25 miles and noticed oil spray all over front of the toad.

Shop thinks it's the new turbo that's causing blow-by, blowing oil out of crank case vent tube. This is because the new turbo is providing more boost. I never had any oil spray before the new turbo installation even with normal turbo boost while climbing steeper grades (about 28 lbs).

Turbo Boost on the way to the shop before new turbo 25 lbs.
Turbo Boost after new turbo 25 lbs (grades not steep enough to require full boost).

Why is there oil spray now, even though boost pressure is about the same?

Could it be a problem with the new turbocharger (maybe a failed seal) forcing pressure back through the oil drain hose and over pressuring the crankcase? Or could it be something else?

Thanks, Bill

Bad rings on the piston's will make/create crankcase pressure, the turbo will not cause this............as it seems the boost pressure is about the same as it was.
Where is the oil coming from?
What year engine is it?

[Tony Lee]

I'd be driving 25 miles back to the shop and getting them to fit another new turbo without an oil leak from the turbo bearings.

[dennis45]

Bill, you have two problems.

One, your new turbo is NFG.

Two, your repair shop is also NFG.

A new turbo won't cause a worn out engine in 25 miles. Not sure how you can resolve this but I think I would start with the Service Manager and insist the problem be rectified No Charge.

[Unplanned Tourist]

Originally Posted by dennis45

Bill, you have two problems.

One, your new turbo is BAD.

Two, your repair shop is also BAD.

A new turbo won't cause a worn out engine in 25 miles. Not sure how you can resolve this but I think I would start with the Service Manager and insist the problem be rectified No Charge.

I agree, sounds like the turbo is leaking boost back into the drain, pressurizing the crankcase, forcing oil out the breather. I have seen this happen before. I suspect the seal was either installed wrong or broken when assembled.

[billfz]

The engine year is 2006 400ISL and I am told the oil was coming from the crankcase vent. I got the news last night and I think Cummins only checked the crankcase vent for pressure as I think the service advisor told me what the pressure was and what it should be. So, I don't think they checked the turbo for blow-by.

There was no oil spray before the new turbo installation and the boost pressure was about the same with both the old and new turbo as the road grade was about he same going and coming.

Cummins, is telling me the pressure increase with the new turbo is making the problem show up. However, the engine never experienced oil spray with boost pressures in the recent past between 25 and 30 lbs.
Bill

[billfz]

Thanks guys for your quick response! I'll be at Cummins Monday to have a talk with them. I know they have it in their minds that the engine is trashed.

The first thing that I want to know is how they diagnosed the problem.

The turbo replacement is also good reading, I'll start a new thread on it.

Bill

[Pusherman]

Before you take it back to Cummins, check the engine oil level. It would be good data to have to determine how much oil blew out.

Also, small possibility they overfilled the crankcase and the extra oil blew out.

[Steve Ownby]

Originally Posted by billfz

Thanks guys for your quick response! I'll be at Cummins Monday to have a talk with them. I know they have it in their minds that the engine is trashed.

The first thing that I want to know is how they diagnosed the problem.

The turbo replacement is also good reading, I'll start a new thread on it.

Bill

Is this a Cummins owned shop or a Cummins authorized repair facility?

[billfz]

I thought about the possibility of oil over fill as the engine was serviced while in the shop. This is a Cummins authorized repair facility!

[billfz]

They also replaced the air dryer filter, could anything with the compressed air system cause the engine blow-by issue?

[palehorse89]

Originally Posted by billfz

I thought about the possibility of oil over fill as the engine was serviced while in the shop. This is a Cummins authorized repair facility!

Have you checked the oil level on the dip stick..........
If they over filled it, it will push the oil right out the crankcase breather tube........

[palehorse89]

Originally Posted by billfz

They also replaced the air dryer filter, could anything with the compressed air system cause the engine blow-by issue?

No........

[Steve Ownby]

Originally Posted by billfz

I thought about the possibility of oil over fill as the engine was serviced while in the shop. This is a Cummins authorized repair facility!

You don't trust that shop and you shouldn't. You need to get your coach to a Cummins owned shop and let them troubleshoot.