603 injector pump re-seal

[PaulSpringmann]

I recently replaced all the gaskets on my 603 injector pump and after 2000 miles, everything is completely dry. I am very pleased. I had replaced the delivery seals some time ago, but the pump was still leaking oil and pooling at the motor mount. Here are some notes. There are 6 seals available from MB which I replaced.

001 074 11 80 side cover: this is easy to replace; flat head screws easily accessible

001 074 43 80 rear lower cover: need to remove cruise control; flat head screws

013 997 81 48 o-ring on back for idle control: need to remove cruise control; I doubt this was leaking on my car, but I replaced it anyway

004 997 46 40 bottom cover: this is the most tedious. There are 6 T30 torx screws; I was able to access with a 1/4" drive torx bit from autozone and a 1/4" rachet. Time consuming, but definitely can be done with the pump in the car on a 126.

010 997 56 48 o-ring for vacuum stop on top: I had already removed the intake because I replaced the glow plugs at the same time. The control-rod sensor connector is in the way of one screw; turn the retainer hard counter-clock wise, remove the connector. Remove the o-ring, and the retainer will lift off making the screw easily accesible.

000 091 17 80 fuel pump gasket: easy to replace

I also replaced the 3 plastic fuel hoses, 603 070 01 32, 601 070 02 32, and 603 070 00 32, probably not necessary, but easy to do with the intake removed.