A/C vacuum switch

[mopowers]

I tried bench testing an original A/C switch like the one in the picture below. When I apply vacuum to the vacuum port with all other plugged, there is an obvious leak in all button positions. I'm sure the leak is small, but I'd assume the engine would not like it. How tight are these switches supposed to be? Is there an acceptable amount of leakage?

Also, I've seen NOS ones on ebay as well as reproductions from Standard. Would a NOS switch be prone to leaking as well because of it's age? Given the choice between NOS and new repro, what would be better?

Thanks!

 

[snailpower]

I went with a NOS one of these and found it to be defective out of the box and had to rebuild it. It still isn't right so I might try one of those repros. when i looked a few months ago I didnt see them still in production though, can you link where you found it?

 

[snailpower]

^ never mind, found it on rock auto. Doesn't list for a scamp but comes up for a valiant. Sadly, as I found earlier it is unavailable when you try to purchase. I found the same dilemma when trying to order from auto zone or other places.

More Information for STANDARD MOTOR PRODUCTS HS101

 

[mopowers]

Yeah, it seems the reproductions are no longer available. Bummer...

I was able to take mine apart and fix it though. I cut a small piece of thin sheet metal the same size as the rubber piece that directs the vacuum signal. Then I doubled up the spring so the rubber piece would seal better. When I got it back together, it held vacuum a lot better. Still not perfect, but close enough to try. If anything, I may run a small 12V solenoid switch so it's only pulling vacuum when I hit the solenoid switch is on. One thing I did learn is these vacuum switch suck and the engineer who designed them was a retard.