Oil dripping from exhaust pipe - PeachParts Mercedes-Benz Forum

martureo · #1 04-18-2014, 01:44 PM

I have no history on this engine. 617.952. I know it has 260,XXX on it. Non driver currently (bought not driving or running).

Small amount of smoke from tailpipe (not any more than any other 617) at idle. Idles smooth. Recently adjusted valves. When in higher rpms and turbo boosting it will drip oil from the exhaust downpipe (only downpipe installed). Drips about once per two seconds.

I suspected the turbo since it will idle without any oil coming out of the exhaust (10 min+). But if I raise the rpms enough to engage the turbo then it immediately starts leaking oil.

Remove exhaust and intake manifolds. Both are internally coated with fresh oil. Loads of oil and oil sludge in the exhaust exit of the turbo. Oil in the intake compressed side of the turbo.

I have a spare turbo (no leaks) and '79 SD manifolds (no EGR) I was planning to install. But can I get a confirmation that this is the turbo leaking and not some internal leak?

rscurtis · #2 04-18-2014, 03:34 PM

I would remove the manifolds and block off the oil feed for the turbo and run the engine. That way, you'll know for sure what the problem is. You'll be able to see if it really is the engine as a whole, or more likely, just one cylinder.

SD Blue · #3 04-18-2014, 05:08 PM

I definitely would NOT block the oil feeds to the turbo. That would be blocking primary pressure from the oil pump. You will find out how much oil is pumped through there if you ever overlook or drop the feed tube washer at the oil filter housing. (A gallon of black sooty oil ended up on a friends driveway in a matter of seconds.)

As many folks, here on the forum, have suggested, check the turbine wheel for any play especially axial. From your description, it sure sounds like a turbine seal. There are a few DIY threads about using a rebuild kit and from what I can tell, it doesn't sound extremely difficult to install.

The only other area might valve guide seals but I'm thinking there wouldn't be intake oil if this is the case.

rscurtis · #4 04-18-2014, 05:36 PM

Blocking the turbo oil feed won't hurt anything- that's what the pressure relief valve is for. Besides, the bearings, cam lube system and piston nozzles will still consume plenty of oil. The turbo probably consumes the smallest amount of oil in the entire system.

Diesel911 · #5 04-18-2014, 07:01 PM

If you remove the Turbo Expansion Joint and look in side and there is a lot of shiny Carbon you most likely have an Oil leak in the Turbocharger Seals.

When you remove the turbl look into the Exhaust Manifold. If inside the exhaust Manifold has that wet looking shinly Carbon the Oil is coming out of the Engine.

When the Carbon in the Manifolds or Turbo is normal it is extremely dry flat black looking color.

martureo · #6 04-19-2014, 11:00 AM

Manifolds off. Oil in compression side of turbo and exhaust of turbo. Fresh oil in all exhaust and all intake ports of head.

Valve guide seals?

Diesel911 · #7 04-19-2014, 11:50 AM

Quote:

Originally Posted by martureo

Manifolds off. Oil in compression side of turbo and exhaust of turbo. Fresh oil in all exhaust and all intake ports of head.

Valve guide seals?

It is hard to tell if you have more than one problem or not. Could be the Compressor Side Turbo Seals. But if that was so you would think that the Car would have smoked more.
But the Blow By can also make the intake wet with Oil if you have enough of it.

Along with Valve Guide Seals there is wear in the Valve Guides and the Valve Stems.

I have replaced the Valve Stem Seals before and even good quality Seals are cheap and the job is not diffiult but it is time consuming.

I used a Pipe Bushing to push the Seals down.

martureo · #8 04-21-2014, 06:51 PM

Ran it without manifolds. No oil from any intake or exhaust port. Placed a piece of cardboard on the manifold studs. Plenty of soot from exhaust ports.

Lots of crankcase pressure.

Can I assume now that the oil leaking from the exhaust pipe was indeed caused by a leaky turbo seal?

Om617.952 83 300D 260k. Running without manifolds - YouTube

Update: revved the engine and I do have oil coming from exhaust ports. What do I do now?

Diesel911 · #9 04-21-2014, 09:32 PM

Quote:

Originally Posted by martureo

Ran it without manifolds. No oil from any intake or exhaust port. Placed a piece of cardboard on the manifold studs. Plenty of soot from exhaust ports.

Lots of crankcase pressure.

Can I assume now that the oil leaking from the exhaust pipe was indeed caused by a leaky turbo seal?

Om617.952 83 300D 260k. Running without manifolds - YouTube

Update: revved the engine and I do have oil coming from exhaust ports. What do I do now?

Does it look as if the Oil is running down the Valve Stems? On Exhaust Valves if Oil is running down you will often see a heavy Carbon Build up and it will be shiny black in color.

If oil is coming from the inside of the Engine it is either Piston Rings/Cylinders issue or a head gasket issue.
If Oil is really getting inside the Cylinder often if you pull an Injector and look inside of the Prechamber there will be a Carbon Build up and it can also also be wet and shiny looking.

dude99 · #10 04-21-2014, 09:58 PM

Agreed, is it smoking at all? My bet is that its water and soot...

martureo · #11 04-21-2014, 10:25 PM

Quote:

Originally Posted by Diesel911

Does it look as if the Oil is running down the Valve Stems? On Exhaust Valves if Oil is running down you will often see a heavy Carbon Build up and it will be shiny black in color.

If oil is coming from the inside of the Engine it is either Piston Rings/Cylinders issue or a head gasket issue.
If Oil is really getting inside the Cylinder often if you pull an Injector and look inside of the Prechamber there will be a Carbon Build up and it can also also be wet and shiny looking.

I did not look at the valve stems. The cardboard in the picture was put in place and the engine revved, the exhaust areas were sprayed with a fine mist of oil.

Bluish smoke.

On all ports there was a carbon build up and on most fresh oil.