1993 300D - New Head Gasket? Leak in the Manifold - Page 3 - PeachParts Mercedes-Benz Forum

BullGator2020 · #31 06-15-2014, 05:04 PM

Happy Fathers Day!

So i performed one of the test that was suggested above. I had the exhaust manifold off and the turbo off. I put the turbo oil feed line into a cup and cranked the engine. As soon as a cranked it, for 2 seconds a huge amount of oil came through the feed line filling the bottom of this cup. I wonder if this is the cause of the problem... To much oil being fed into the turbo therefore passing the seals and leaking into the exhaust and manifold. How much oil is suppose to go into the turbo?

Here is a pic

97 SL320 · #32 06-15-2014, 10:26 PM

The turbo will take as much oil you can give it. The bearings provide a flow restriction, once the oil passes the bearings it drips into the return tube then to the oil pan.

There are a few ways to test for turbo oil leaks. ( for all of this, keep flammable stuff away from open exhaust. )

To test for leaking turbo, remove it from the exhaust , block the oil feed and return tube then run engine. The turbo oil feed block off must take ~ 80 PSI without leaking.

Another way would be to remove turbo from exhaust, leave oil feed attached, extend the oil return with a piece of heater hose ( or similar ) then run the engine and look for oil leaking from the turbo.

ROLLGUY · #33 06-16-2014, 12:51 AM

Quote:

Originally Posted by 97 SL320

Another way would be to remove turbo from exhaust, leave oil feed attached, extend the oil return with a piece of heater hose ( or similar ) then run the engine and look for oil leaking from the turbo.

I have been suggesting this all along, as it is the only way to test the seals in the turbo. No need to attach any kind of hose to the drain tube. The turbo will rest on the drain tube and be held in place by the oil feed tube. As long as you don't drive the car around and just test it while parked, you should find out right away if the turbo is bad.

BullGator2020 · #34 06-16-2014, 08:37 AM

Do I need to put back on the manifold to do this test?

Also, I am looking for oil coming from the back of the turbo right?

ROLLGUY · #35 06-16-2014, 11:04 AM

Quote:

Originally Posted by BullGator2020

Do I need to put back on the manifold to do this test?

Also, I am looking for oil coming from the back of the turbo right?

No manifolds, just the turbo with it sitting on the oil drain tube and the oil feed line hooked up. If oil is coming anywhere out of the turbo, you have found your problem.

97 SL320 · #36 06-16-2014, 06:10 PM

Quote:

Originally Posted by ROLLGUY

I have been suggesting this all along, as it is the only way to test the seals in the turbo. No need to attach any kind of hose to the drain tube. The turbo will rest on the drain tube and be held in place by the oil feed tube. As long as you don't drive the car around and just test it while parked, you should find out right away if the turbo is bad.

Yea, I know but the original poster can't / won't do a leak down test.

Leak down is my go to test that can be done in very little time.

ROLLGUY · #37 06-16-2014, 10:12 PM

Quote:

Originally Posted by 97 SL320

Yea, I know but the original poster can't / won't do a leak down test.

Leak down is my go to test that can be done in very little time.

Yes, but since the manifolds are already off, 2 bolts and a couple minutes later he would know if the oil is coming from the turbo or not. A leak down test would point to a different source of the oil, but would not tell if the oil is coming from the turbo.

BullGator2020 · #38 06-17-2014, 09:24 AM

Thank you all so much for sharing this knowledge!

So I completed the test by hooking up just the turbo. I cranked the engine (it actually started and ran for about 3 seconds) which is crazy considering the exhaust was out, manifold, etc...

When I removed the turbo, there was no oil in the back of the turbo, the only oil present on the turbo, was in the front outer part which seemed to have been sprayed from the exhaust ports (Nothing inside the front)

It is starting to look like the turbo is ok.

So now that I eliminated the turbo as the source of the leak. The only other information I have is that ports 1 - 2 of the manifold were completely coated with oil.

What do I do next?

Here is a pic of where the oil was coming out of:

funola · #39 06-17-2014, 10:08 AM

Could broken valve guide(s) do that?

jt20 · #40 06-17-2014, 03:31 PM

I'll say it again, for many that are thinking the same thing.

The most reasonable assumption (made about 30 posts ago and on another thread) is that you have a failed headgasket.

move on.

BullGator2020 · #41 06-17-2014, 04:05 PM

I wanted to make sure that the failed head gasket was the route to go... So at this point I'll start removing the parts to expose and examine the head gasket.

97 SL320 · #42 06-17-2014, 05:58 PM

This isn't a head gasket failure. Head gaskets can fail in the following ways: ( most common to near impossible )

Between the combustion chamber to coolant. ( coolant out the exhaust , bubbles in the coolant )

Between two cylinders. ( Loss of compression. )

Between coolant and outside the engine. ( will leak on the ground )

Between the oil feed passage and outside the engine ( not so common. )

Between the oil feed passage to a _single_ cylinder. ( theoretically possible but I've never seen it. However you would hydralock a diesel engine with any amount of oil. )

Between a oil return passage and a cylinder. ( the return side is gravity so having this occur is essentially impossible )

I've been in and around the auto repair business for 40 years and have repaired countless engines. A leak down test will tell what you need to know. If you don't have an adapter for a glow plug, use a compression tester adapter with the check valve removed ( usually a tire valve type ) or use a rubber tipped blow gun. With the amount of oil blowing out, you will have lots of air coming out of the oil cap.

You either have a cracked piston or possibly a valve that fell out of the keepers and has dropped out of the guide.

ROLLGUY · #43 06-17-2014, 10:36 PM

Well I am glad to hear that it is not the turbo, and that the test proved it. If the valve keeper came off, wouldn't one be able to view the valve from the open port and see if something is amiss? I am sure if it was something with the valve or a cracked piston, it would not run well. Has anyone addressed this? Definitely a leak down test is in order.

BullGator2020 · #44 06-18-2014, 08:44 AM

I really appreciate everyone's input.

Originally the symptoms I was getting, was significant blow by and oil dripping out of the exhaust. The car for the most part was running fine, other than a performance issue when I accelerated, which after reading other posts could be related to the ALDA, but that is a different issue.

So I don't believe a piston is cracked but who knows.

I will run a leak down test as you suggested. I haven't inspected the open port to see if something is amiss.

I don't have a glow plug adapter so I will make adjustments you suggested.

97 SL320 · #45 06-18-2014, 11:01 PM

Quote:

Originally Posted by BullGator2020

I really appreciate everyone's input.

Originally the symptoms I was getting, was significant blow by and oil dripping out of the exhaust. The car for the most part was running fine, other than a performance issue when I accelerated, which after reading other posts could be related to the ALDA, but that is a different issue.

So I don't believe a piston is cracked but who knows.

I will run a leak down test as you suggested. I haven't inspected the open port to see if something is amiss.

I don't have a glow plug adapter so I will make adjustments you suggested.

O K. . .. .( long drawn out pause ) . . . . You have significant blow by and oil dripping out the exhaust. Where do you think the blow by gasses are coming from? ( Blow by is defined as: combustion gasses making their way into the crankcase. )

The engine is already broken the way it is broken, not wanting it to be broken in that way won't change that.

Read this thread how could my om617 be compromised so quickly? and look at the pics in post 43. The owner is so delusional he claimed that a previously good running engine was damaged in the length of a couple of city blocks at 35 ish MPH by a " botched oil change using a pair of too small oil filters ". ( He had a double filter mount, these are usually a parallel system to allow for more flow. )

I stated these 2 filters still had more surface area than one stock filter but he ignored that. Also, the connecting rod bearings are in excellent shape and not starved for oil.

Later, in post 63 he claimed the pics that _HE POSTED_ in post 43 were faked. . . Someone else in post 66 felt the same way so and summed it up beautifully.. . . This thread is starting to get that feel.