1971 Vapor Cannister valve
Thread Starter
Melting Slicks
Joined: Apr 2010
Posts: 2,793
Likes: 1,192
From: Canberra Australia
2025 C3 of the Year Finalist - Modified
1971 Vapor Cannister valve
Started to rebuild the vapor canister I picked up a while ago.
First I removed the filter
Then I removed a lot of old foam that was crumbling away inside.
All the charcoal then was able to be taken out and I was left with some more old foam rings inside.
I thought the best thing to do would be to test the operation of the valve.
Dissembled the valve and cleaned all the parts.
After some lubricant on the diaphragm it went back together.
Applied vacuum to the PCV tube and it held vacuum fine.
Then applied vacuum to the carb tube and it opens valve and allows PCV tube to extract contents of the canister.
Problem is it never closes again unless I take it apart and put back together again.
Not sure if I have done something wrong or I am applying too much vacuum and distorting the rubber diaphragm
Any ideas ?
First I removed the filter
Then I removed a lot of old foam that was crumbling away inside.
All the charcoal then was able to be taken out and I was left with some more old foam rings inside.
I thought the best thing to do would be to test the operation of the valve.
Dissembled the valve and cleaned all the parts.
After some lubricant on the diaphragm it went back together.
Applied vacuum to the PCV tube and it held vacuum fine.
Then applied vacuum to the carb tube and it opens valve and allows PCV tube to extract contents of the canister.
Problem is it never closes again unless I take it apart and put back together again.
Not sure if I have done something wrong or I am applying too much vacuum and distorting the rubber diaphragm
Any ideas ?
