power steering box leaks

[Nick Ludovic]

The power steering box on my '87 300D developed a sudden leak, emptying the contents of the reservoir completely after a 25 mi. drive. The leak is coming from the steering box input seal. I have removed the box from the car and have obtained a seal kit which looks to contain all of the seals and ring for the box. Does anyone have tips on replacing the seals and disassemblying the box to inspect the other seals. The car has 155,000 mi. and the steering seems normal.

[Robert Goodwin]

Why is it that Fords and Chevys seem so much easier to repair than Mercedes? There is a lot of anecdotal information on the American (content) cars right on our own block. Everyone owns one or two. In order to do our own repairs on a Mercedes, the neighbors are of little assistance. In order to tackle such jobs, I would encourage you to buy the repair CD put out by Mercedes or at least one of the aftermarket repair manuals at McParts, if it has the information you are looking for. Public libraries are another source for the aftermarket manuals. A glance at the 37 pages of information on refurbishing the box reveals nothing sinister in replacing seals, only for measuring gears and things.Since the parts in the unit are swimming in ATF, you can conclude that if "it" comes off, there is a seal or O ring on "it". Perhaps someone with more hands on experience than I can shed more light on the issue.

[Nick Ludovic]

Thanks for the direction to buy the CD. I replaced both the Pitman arm and input steering seals, everthing else looked OK. I did have an initial leak from the Pitman arm seal when first starting but after steering back and forth the leak stopped, may have been a little rust left on the shaft.

[Robert Goodwin]

Nick,

Glad to hear that things worked out for you. I wish I could stop all the leaks in my 2 diesels, but there is not enough time or money to get them all at once.