As discussed in this post

Oil coming UP the cyclone drain tube!!!

My car has an annoying leak near the turbo and oil separator drain tubes. I replace the turbo drain tube grommets and gaskets in this post

617 Turbo oil return line. Replacing seals

I replaced the O rings in the oil separator drain tube and still had the leak.
My theory is that the check valve was remaining open allowing oil to be sucked up the drain tube, OR the valve was stuck closed and not allowing the oil in the tube to drain after engine shutdown. With the engine running I’m sure that there is always a vacuum, caused by the turbo, in the oil separator/drain tube area. To prevent the oil in the oil pan from being sucked up into the air filter assembly, the check valve shuts off the oil pan air going into the drain tube. Then all the air/oil from the PCV tube going into the oil separator accumulates in the cyclone bowl and drains down the tube. When the engine is shut off the check valve in the upper oil pan opens and allows the accumulated oil to drain. At least this is what I have concluded. Is this the way the system works?? Not 100% sure but the theory seems logical. If anyone else has a better idea please speak up.

Parts needed.
1. A new check valve.
2. A new holding sleeve.
3. A new lower oil pan gasket.
4. 8 quarts of oil.
5. A new oil drain plug washer
6. A new filter if you want to do this.

Torques for the bolts.
Drain plug 35-45 Nm (25-33 Ft Lbs)
Oil pan bolts 9-11 Nm (6-8 Ft Lbs 79-97 Inch Lb )


Photo#1. Is the oil separator setup in the 617 engine. Item number 7 is the check valve and the drain tube is highlighted in red.

Photo #2. This is the problem. The result of what I think is a failure of the check valve to operate correctly. After removing the check valve I found it to operate poorly and intermittently.

Photo #3. Another view of the area where the oil is leaking

Photo #4. These are the tools I used doing the job.

A. Lots of shop rags. The oil pump will continue to drip while the oil pan is off, annoying and messy
B. A inch Pound torque wrench to tighten the oil pan bolts. Attached to it are a ¼ drive extension and a 5MM allen head socket.
C. A paint scrapper to completely clean the upper oil pan matting surface for the power oil pan.
D. Pliers to remove the holding sleeve.
E. A 5MM allen T wrench to remove the oil pan bolts.
F. A 10MM socket set and extension to remove the air filter assembly.
G. A 13MM box wrench to remove the oil drain plug
H. Lots of degreaser.
I. A brass punch to drive the holding sleeve into the upper oil pan.
J. A hammer to, well you know what a hammer is for!!

Photo #5. These are the 2 parts that you should buy to do the job. The new check valve to the left and a new holding sleeve on the right. The check valve looks a lot like the vacuum pump check valve. I would recommend a new holding sleeve. The old one might not spring back correctly when removing and you don’t want to go back in there to fix that.

continued

Dave

Attached Thumbnails

         

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car