Headlight Vacuum Storage Canister Replacement Question

[91-Vetteman]

I bought a new Headlight Vacuum Storage Canister" (looks like a coffee can) for my 1981 from ZIP and I went to replace it this weekend and it is configured slightly different.

3 vacuum hoses connect to this cannister. On the new cannister one of the hose connections (the smallest diameter hose) is sealed off /closed. The other two connections (the 2 slightly larger ones) are open as the original.

I have an email into ZIP technical folks asking why the difference on the new (I am assuming this is a reproduction cannister) cannister. Does anyone out there have any guesses why the new can would have the one hose connection sealed up ?

 

[craig32]

Hey John, I'm pretty sure my 81 only has two hoses going to it, with the other one sealed, you have a third hose going there?? If I dare ask, what do the canisters go for? I've heard folks say they are pricey.

Craig

 

[91-Vetteman]

Hi Craig, yes, I have 3 hoses, I will try and trace themn down this weekend. Here is the info on the replacement cannister at ZIP, 80-82 VACUUM TANK RESERVOIR, Product Number: M-2661 and it was $45.

 

[91-Vetteman]

I traced my vacuum lines off of the cannister this weekend. One is the supply vacuum and the other two go to each headlight control valve. I also got a response form ZIP technical below. I will be inserting a T as described below.

The reason why the canister only has two holes is because it is a reproduction of the 82. The 80-81 had 3 holes in it and when the last GM that you could buy only had two ports. You are going to have to T one of the vacuum lines off, you want to T the lines that come out of the canister going to the headlights. Do not T the line that supplies the vacuum.

 

[minifridge1138]

I have heard that Zip's vacuum diagrams are wrong.
I would just install it the same way the old one was installed.

If you don't remember how the old one was, then I'd try a Chilton's, Hayne's, or GM Assembly Manual.

Good luck,
(p.s. i former chevrolet mechanic told me that it actually IS a folder's coffee can)