C2 A/C Vacuum Shut-off Switch O-Ring Size???

[James W.]

I did a search regarding the C2 a/c vacuum switch for details regarding whether or not I should be hearing an audible vacuum leak from the cacuum switch when the car is running. I did not find any info related to what I am asking and I am assuming that I should not be hearing the vacuum leak at the switch. I did come across the post from February of 2008 regarding replacement of the original brass vacuum switch o-ring but there was no mention of what size this o-ring is.

I am in the final stages of a heater core change out in my '65 and I'm testing everything as I am putting the car back together. As I was testing the new heater core and related heater hoses for leaks and heater/hot water control function last Friday I noticed an audible vacuum leak in the car as it was running and traced it to the vacuum switch which was leaking.

My question is has anyone since the posts back in february of 2008 determined what size the vacuum switch o-ring is?

An help would be greatly appreciated.


Thanks,

James West

[Mike G.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

Jim: when I rebuilt the vacuum switch years ago, I could NOT find an o-ring of the right ID/OD. The original seal wasn't an o-ring at all, it was more of a "sleeve". And forget about trying to find one of those...

The fix: found an 0-ring with the correct ID, but a little big on the OD. I resized the OD by slipping it onto a bolt shank, chucked it up into a drill motor, and sanded it down to the correct OD.

As I recall, it took 2 o-rings to make the switch function as original.

Of course, use a generous amount of vacuum grease when reassembling.

[James W.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

Mike,

Thanks for the reply. When you say two o-rings, I assume you mean two of them set side by side inside the bore... correct?

Any hints or do's and don'ts I should know about when disassembling the vacuum switch?


Thanks,

James West

[Mike G.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

James:

It's been too long, but I was able to figure out the o-ring positioning by understanding the mechanical design of the plunger relative to the ports.

I didn't try to swedge the body to hold the plunger in. Just used a drop or two of varnish. Super glue would be fine too.

If all else fails, this switch is available for about $60.

[Wayne M.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

My question is has anyone since the posts back in february of 2008 determined what size the vacuum switch o-ring is?
James West

James -- did that thread of Feb 2008 refer to the rebuild article on Dr. Rebuild`s website. do a search under "geoffrey coenen" (sp ?). He described the rubber rings, R & R procedure, and where to obtain.

I haven`t tackled my valve yet (on my list) -- Good luck

[James W.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

James -- did that thread of Feb 2008 refer to the rebuild article on Dr. Rebuild`s website. do a search under "geoffrey coenen" (sp ?). He described the rubber rings, R & R procedure, and where to obtain.

I haven`t tackled my valve yet (on my list) -- Good luck

Wayne,

Yes it did reference the repair procedure. I was hoping someone since then had specified the size of the o-ring(s) needed to make the repair to the vacuum switch. Maybe that someone will end up being me?

Thanks,

James West

[Mark U.]

Re: C2 A/C Vacuum Shut-off Switch O-Ring Size???

i just replaced the brass vacum switch purchased from ebay as new.works great.