I am missing something here.
I have tried Rogers, 7T1 Vettes and Corvette 101's relay tests on 3 spare relays. Two are brand new. None will hold vacuum on the big center (yellow) port with either red or green plugged off :l

 

Hard to find good relays.

 

When I flip the relay upside down and push the valve down then seal the metal port it stays down and springs up when I unseal. Is that a qualifier ?

 

That just means the diaphram in the control end is good. The problem with these us what you are experiencing, the seals for the internal spool are leaking.

 

Search the forum for headlight vacuum relay and you can see where a few of us have been able to repair them.

 

 

http://forums.corvetteforum.com/c3-t...ay-valves.html

This is what I needed. I am putting here mostly so I can find it when I need it next weeekend.

I wonder if I will ever drive this car

 

Right now, at this moment I am soooooo bloody choked at all the people that sell these vacuum relays. They are garbage as they are being packaged and shipped to your house. I have WAISTED so much bloody time on thse things and bought parts I didn't need because the relays were NEW. They're junk !

 

Sucks, huh? (pun intended)

 

There is a way to get the original relay [shuttle valve] to seal; I would assume that it will work with the 'new' aftermarket parts, but I have not tried it. It involves disassembling the relay by used a Dremel with grinder tip or cut-off wheel to remove the '****' (sorry, ladies) on the end of the diaphragm rod, to which the shuttle valve is attached. Here's the process for those not 'faint of heart':

1. remove 'cap' in valve bore at bottom end of relay;

2. extend relay diaphragm rod so that swedged part of rod and '****' are exposed; with Dremel, remove only the outer portions of the swedged areas, so that you can remove the shuttle valve from the rod;

3. Save small washers on either end of the shuttle valve for later use;

4. For each relay you want to salvage, purchase (2) two 5/16" diameter O-rings, with 1/16" cross-section from a hardware store [most have a tray with many sizes of O-rings].

5. on each shuttle valve, depress an O-ring into the recesses at the ends of the valve; if they don't want to stay in place, you can use just a light wipe/dab of RTV (not regular silicone caulk/sealer) on the outer diameter of the O-ring so that it will adhere to the inside of the valve seal; let RTV cure.

6. Put wipe of white lithium grease on each sealing lip of shuttle valve, then install parts in bore and over rod: washer, shuttle valve (with O-rings at each end), the other washer. Slide all parts just past the old swedged area. Use forceps clamp or other small clamp to keep shuttle valve in place, then apply small bead of JB weld epoxy over the old swedged area to retain the valve in place. You want some compression on the valve and O-rings via the washers, so that the O-rings will force the shuttle valve sealing lips outward and re-establish the seal(s).

7. Once the epoxy is cured, remove clamp, reinstall end cap and test it with vacuum on [and off] diaphragm. Or you can reinstall on the car and test the headlights with the 'salvaged' relay.

As I stated, I have successfully done this on an old 'factory original' part. I am not familiar with the 'guts' of the aftermarket parts, but if they are essentially the same, this should work for them, too. Of course, you will then not be able to return that part to the vendor for reimbursement. But, you should end up with a working, servicible part.

Hope it works for you. Let me know.

 

Thanks for the response 7T1vette

Cooled off a little now. I tried what you suggest above. Unfortunately I only succeeded in mutilating the cup on the end of the spool.
I had 3 left (2 brand new) and I decided to cut the rings off the top. I have them rebuilt with #8 o-rings and they work great squeezing them together with 1 hand.
The problem is the rings can never work again. They are as soft as solder...useless. I have to figure out how to seal them up without the rings I cut off now.
None of the 4 I had would hold vacuum including the one in my neigbors yard, I will get it after dark. In one of the new ones the spool was obviously shoved in dry, the lip of the cup was folded right over.
I don't know how these vendors can shoot this crap out the door without spending 3 minutes testing it 1st. I bought these things 3 or 4 years ago so i'm stuck with them now.

JR

 

Just to be clear,your applying vacuum to the center port with the lower port(green)blocked with no vacuum on the small hose port at the top ?

 

Thats right Roger I can get a seal no problem now. I can hold the top shut with my hand. I just have to figure out how to replace the ring around the top. Would you believe that there are no tin cans that have the same ID as the relays OD. Libbys Beans was so close but no cigar.

 

I only did one relay by removing the metal top ring, but I didn't cut it , I just unbent it all the way around and then crimped it back together going back together.

 

Thats definitly were I went wrong Roger. I spent the day with calipers in heating and plumbing stores. I found some stainless exhaust tubing that is just the right diameter. I'm going to cut a few bands and see if I can fold them over and get a seal. I don't have high hopes but I sure don't want to buy even more of this junk. And that will be my Sat. night.