AC Vent Door Eye Loop

[tucsonjwt]

I am putting back together the interior of my 83 C20 with factory ac and I can't remember what this center loop feature is for. I think the silver colored u shaped hook with the teflon speed nuts attaches to the vacuum canister bracket, but I don't know if this center loop connects to anything. Can anyone identify the purpose and connection (if any) on the circled loop on the vent door? Thanks.

[Dead Parrot]

A spare one of those on my shelf has a spring hanging off the circled thing and the vacuum pot connected to the silver U.

[tucsonjwt]

Can you post a pic of that spring? Thanks.

[tucsonjwt]

I found a 73 C10 with factory a/c at the Pull-A-Part. The spring connects to a small hole in the bottom of the vacuum canister bracket. I found my missing spring after I bought the "plenum valve" assembly with spring attached. Thanks for the help.

[Dead Parrot]

Glad you found a useful part. This is a pic I took of the one on my 75 before seeing you had solved your question. In case someone else has a similar question.

[tucsonjwt]

One difference is the kick panel cover on my Silverado is much larger than the half size panel on the basic trucks. I think the one I got off the junkyard 73 also has a somewhat smaller plenum valve, but I have not taken the two apart to compare them.