Yes your bracket is probably broken as was mine. I fixed it by taking some fuel hose about 3/4 inch long, slipping it over the protrusion in the bottom of the air cleaner, then fitting this into the metal tube. When you clamp the air cleaner down it makes a very tight leak proof fit. I also took 2 zip ties and secured the fuel hose to the air cleaner just to make sure it would not vibrate loose. It works great and is very stable.

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
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I love the smell of diesel smoke in my hair