Replacing Seals on Turbo Oil Drain Pipes - OM617.9xx


Replacing Seals on Turbo Oil Drain Pipes



DISASSEMBLY

1.Clean the area thoroughly; otherwise it will be difficult to keep flanges clean during reassembly. Take off the air cleaner and the U-shaped plastic pipe.

2. Loosen the two bolts that hold the drain pipes to the turbo with a 3/8" drive 13 mm socket that has rough surface tape wrapped around it (Two cloth bandaids, for example). As soon as the bolts turn freely finish unscrewing the bolt with the socket only.

3.Shoot some penetrating oil up into the pipe joint and push the top pipe down.

Pry the grommet out of the engine block. Inspect it carefully and compare it to the new one. If it's not all there, take a sharp tool of some kind and fish for the missing chunks. Shoot some penetrating oil around the bottom pipe and work it loose in the engine block using channel pliers.

4. Lie on your back and look up at the mounting flange on the turbo. Shove the top pipe just past this flange toward the passengers side of the car. Hold it there and push the center joint toward the front of the car. If you can't separate the pipes, move the top pipe to get it in a little different position; you might have to do this several times.

5. If the pipes still can't be separated, check the engine hole for chunks of rubber again and slide both pipes up and down at the hole and the joint several times using channel pliers with more penetrating oil. Repeat step 5. You might have to repeat steps 5 and 6 several times.

6. Take the old gasket off the flange if possible. It may be stuck so tightly to the turbo flange it can't be removed. If it hasn't been leaking it might be a good gamble to leave it and reassemble the flanges with non-hardening Permatex or equivalent. Otherwise you might have to take off the turbo to remove the old gasket.

REASSEMBLY

1. With a file and sandpaper, smooth out any rough spots on the straight pipe caused by the channel pliers.

2. Grease the ends of the straight pipe and the inside of the grommet, and force the grommet to the center of the pipe. Put the greased O-rings on the ends of the pipe.

3.Grease the inside of the hole in the engine thoroughly. Stick the straight pipe in the hole in the engine block with the correct end of the grommet facing down. Force the pipe into the hole until it snaps into position and you can't pull it back out. You can pull it down with a claw hammer and block of wood to protect the end of the pipe. Don't seat the grommet yet; leave it up on the pipe.

4. Grease the inside of the flared end of the top pipe. Lie on your back and put the pipe flange in the same position you did during disassembly; just past the turbo flange. Push the bottom pipe toward the front of the car. You should then be able to get the top pipe over the bottom pipe and pull the top pipe down. Several tries may be necessary.

5. Position a new gasket or coat the flange with non-hardening Permatex spread with your finger. If you coat the flange before putting the pipes together it's difficult to keep grit/dirt off the flange unless the engine has been steam or pressure cleaned.

6. Start both bolts and tighten with bare socket. Finish tightening with rachet (one click at a time). Push the grommet down into the engine block. Reinstall the air cleaner and pipe, being sure the air cleaners oil drain pipe is connected to the air cleaner.

By Gerry Archer







Ref: Frank Mallory's database and https://mercedes-benz-publicarchive.com