I've had my 1982 300TD-T for 2 weeks now, and I'm getting around to all the little things that have been neglected for who knows how long...

One of those things were the rubber air filter housing mounts. When I took delivery of the car, I noticed that the housing was loose, but during the test drive it made no noise - even at idle.

So, I went out and purchased new mounts (and heat cups, which weren't there beforehand) from my local Benz dealer and installed them, along with new seals for the turbo-to-air filter-housing hose. (By the way, do those new seals add a little extra oomph above 2000 rpm, or is that my imagination?)

Anyway I now have a rattling housing at idle, and at speed going over rough road surface. Sounds like the housing smacking into the valve cover, definitely metal-on-metal.

The bracket itself is in rock solid shape. I've tried repositioning the housing using the two different mounting positions. I tried removing the heat cups.

Any ideas?