I tried a number of parts places...they all want to sell the entire air box.

It is not worth it for me going to a pick and pull to spend an entire day removing a dashboard and the entire air box for just that one part!!! And as they get old they get brittle so even if I was careful it is possible it could break during the removal. Imagine 7 hours out there and in the final steps the plastic neck shears off!!! Or after a successful removal putting it into my air box and seeing it shear off...

My first attempt at a fix was gluing the old one which had a perfectly clean break. It seemed like it would work but when I was putting the heater core in I forgot to close the legroom doors which put pressure on the glued flap. That broke it. I decided that gluing really wasn't a solution. Going through all this work for things to be marginal doesn't make sense to me.

I've decided the best solution is to buy the right side new (just over $40) and fit it. The trick to doing this is scrubbing all the foam backing off the opposite side and then applying a thin layer of felt tape to the side that seals it. The clearance is slightly off but without the foam backing on the one side I think it will work. The trick is to get that thin felt on there because if something doesn't buffer the door it will bang. If it bangs repeatedly it will probably break the neck or the plastic receiver with time.

Fabricating one would be interesting but I do not have the knowledge or capabilities to do it. I hope this post is useful to someone someday.

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1984 300 SD 384,000 Miles