If the problem is the bearing in the pulley in the smog pump, instead of replacing the whole unit, which is very expensive, the dealer sells a rebuild kit, which is basically a replacement pulley with a new bearing. I think they run about $200, whereas a new pump is around $1,000.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".