I posted to a query asking about a water soaked carpet on the front passenger side due to water leaking from the a/c. I said that I saw a Volvo factory tech tip #11102 for a/c system drainage through 1989. This was in Import Service Magazine. The tip said clip of the end of the duckbill of the a/c drain hose on the earlier models and press a drain hose insert #P/N354090306-6 into the drain hose. Then reinstall everything. I purchased the insert and was surprised to find that it was nothing more than a delron or nylon plug with a hole down the center. The insert od measures .687in. the hole down the center is .196 in. and it is .795 in. long. I talked to the shop foreman who hadn’t been there before when I was there and she said that they never use the insert. What they do is clip off the end of the duck bill only. This is making me think that all you need to do on the models that use the duckbill style drain hose is clip off the end of the duck bill to let the water drain out. I would try this before I spent $10.00 for the insert