Turbo oil seal gone? 1991 350SDL
 

I have oil seeping from the fittings on the intake manifold so I pulled the crossover pipe to find this
IMG_0424_zps364e81e9.jpg Photo by krwsenior | Photobucket

The car runs great, turbo works good, and there is no oil in the exhaust pipe. If the inner turbo seal is gone, is there a kit available to rebuild it? I'm sure a rebuilt turbo would be expensive. The car has 309k miles and only minor oil consumption. I'm going to pull the intake manifold soon in order to ream the glow plug ports so that will be a good time to clean the intake. I disconnected the vacuum to the EGR valve a few months ago.

Looks like excessive oil going into the intake to me. I'd double check it's not blowby forcing lots of oil out of the breather first.

-J

It has very little blow by when the oil cap is removed. Hardly any at all.

I am by no means an expert. I've been studying for a problem with my '91 350SDL myself and found my turbo leaking oil.

Pull the plastic air pipe that runs from the air cleaner housing to the turbo intake. You can see the intake impeller with this removed. Inspect the intake to the turbo itself. Mine was leaking oil like a sieve and there was oil puddled at the bottom of the intake. You can also grab the nut that holds the impeller to the shaft. See if it has any slop up and down. If it does move the bearing need replacing.

Yes, they sell kits to rebuild these. I found them on line. It's a simple rebuild.

Somewhere on the Aluminum Back of the Compressor Housing; that Part attached to the Center/Bearing Housing there is going to be a small Tag with the Mercedes Part Number and the Garrett/Makers part or Model number.
I am assuming you have a Garrette (Air Research) Turbo. If so there is 3 is 3 possible types of seals that can go on the Compressor end.
A Dynamic type seal = Piston Ring type seal
A Carbon Seal
An Encapsulated Seal

The Turbine end always has a Dynamic/Piston Ring type Seal

It is possible for the Ring Grooves on the Turbine to be worn beyond spec and the Bearing Bores in the Housing and the Bearing Journals on the Turbine Shaft to be worn beyond spec.
No one has posted specs and from what I have read on various internet sites there is no agreement on even what or how to torque the Shaft Nut.

Where to buy parts is somewhere in the below links:
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf

See this thread Post #4; hope the site still works

http://www.peachparts.com/shopforum/diesel-discussion/337812-87-300tdt-turbo-part-identification.html#post3134351

Thanks very much for the help! I now have another thing on my very soon to do list. :)

"While-I'm-At-It-Make-Work: Pull that bad boy down to the block and install new gaskets everywhere. Change hoses also. There is a helpful thread about a leak free engine. No point in going through the hassle of just rebuilding the turbo and not going the short distance to do all.

Junkman, that sounds like a good plan. But this is my daily driver, so I need a little more time available to do that. I may go ahead and fix the turbo, then later do the rest. External leaks are not much at this point.

There is slack in the center shaft, so a rebuild is needed. I cannot find the small tag with the model number. All I can see is a casting for Garrett and for AirResearch. I may have to remove the turbo then order parts. I would prefer to have the parts first since this is my daily driver, but I can't identify the model number.

could it be the blowby from the EGR. I have/had a lot of black oil in the intake of my 85 TD. It dried up once I stopped the EGR leakage.

The Tag is not on the Intake Housing. It is on the ribbed Aluminum Plate next to the Bearing Housing.
The Tag could be smaller than the one in the Pic. Also this is a pic of a turbo with Dynamic Seals.

Thanks Diesel911. That helps. I'll look again tonight.

I had an oil consumption issue with my 91 350sd, om603. Couldn't find it for a while. The underneath side of my hood; hood pad; was getting wet around the oil filter canister. But it wasn't my oil filter housing. Finally figured out my turbo was leaking and making a mess in my intake manifold and oil was leaking out around the boost fitting/line on intake manifold and making a mess. I changed out my turbo with a used one I had with @ 100k on it and went from a liter of oil every 800 miles to @ 1 liter every 1500 miles, with @ 400k on engine. So a seal somewhere in the turbo went bad.

What looks like the end of the turbo to you looks like every 603 with functioning EGR to me. If the oil seal is worn, there'll be a lot of oil on the compressor wheel. Post a picture looking into the compressor inlet with the hose from the air cleaner removed. To confirm, clean the compressor wheel and redirect the valve cover breather hose (I think someone else suggested this) to see if the oil accumulation returns in short order. If not, the turbo doesn't have a compressor side seal problem worth addressing, IMO.

There's always radial play in the turbo shaft. There has to be since it doesn't have roller bearings. You don't want perceptible axial shaft play.

Sixto
MB-less