Vacuum Relay Valves
Thread Starter
Racer
Joined: Jun 2005
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Vacuum Relay Valves
Hi, has anyone replaced their vacuum relay valves with an aftermarket valve and had either their h/l or wiper door oper and close on engine start up as my right h/l opens then closes and I noticed the valve had been replaced, and I had the same problem with the wiper door opening and closing after I replaced that valve and when I put the original one back in the problem went away, I think that the diapham spring inside the valve is stonger than the original ones were, therefore the vacuum going to the acuator is delayed and the end result is it will open then close. (page 12-46 of the 1970 service manual)And I believe the theory of operation is that for the acuators to be in the "closed" position you must have vacuum present and if the vacuum is cut off the acuators open, (at least on the signal line, not the acuators themselves.) Your thoughs? 
Last edited by JIMS1970VETTE; Aug 23, 2005 at 11:53 AM.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by JIMS1970VETTE
Hi, has anyone replaced their vacuum relay valves with an aftermarket valve and had either their h/l or wiper door oper and close on engine start up as my right h/l opens then closes and I noticed the valve had been replaced, and I had the same problem with the wiper door opening and closing after I replaced that valve and when I put the original one back in the problem went away, I think that the diapham spring inside the valve is stonger than the original ones were, therefore the vacuum going to the acuator is delayed and the end result is it will open then close. (page 12-46 of the 1970 service manual)And I believe the theory of operation is that for the acuators to be in the "closed" position you must have vacuum present and if the vacuum is cut off the acuators open, (at least on the signal line, not the acuators themselves.) Your thoughs?
Have you replaced your vacuum check valve lately? It could be weak and the new relay has caused the problem to surface.
Thread Starter
Racer
Joined: Jun 2005
Posts: 312
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Yes I replaced the filter, check valve and ALL the vacuum lines (about 70 feet!) I have gone through two relay valves and one had a leak and the other will cause the acuator to open and close(leaky?) I will try and get NOS next time. 
Last edited by JIMS1970VETTE; Aug 23, 2005 at 01:05 PM.
Race Director
Joined: Feb 1999
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Check them using a vacuum pump before you install them.
1. Apply vacuum to the center port of the body and put your finger over the bottom body port and make sure it holds.
2. Apply vacuum to the top metal port and hold the vacuum by clamping the hose to the metal port. Then apply vacuum to the center body port and put your finger over the top body port and make sure it holds.
3. When you release the vacuum applied to the top metal port the valve should return to its shelf state which should be the same as described in #1.
1. Apply vacuum to the center port of the body and put your finger over the bottom body port and make sure it holds.
2. Apply vacuum to the top metal port and hold the vacuum by clamping the hose to the metal port. Then apply vacuum to the center body port and put your finger over the top body port and make sure it holds.
3. When you release the vacuum applied to the top metal port the valve should return to its shelf state which should be the same as described in #1.
Thread Starter
Racer
Joined: Jun 2005
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Well I replaced the relay valve for the right h/l and the problem went away (opening and closing on engine start up) it seems that the repro relay valves may have a different tension on the internal diaphram than the NOS versions? I dont know for sure but as in this forum as well as word of mouth I have heard there are problems with the repro units. SO stick with NOS when you can
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Le Mans Master
Joined: Jul 2005
Posts: 5,752
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From: Austin Texas
Originally Posted by dyanisis2
did eklers replace the bad relays u bought from them free of charge?
I actually bought 2 relays from The Last Detail- and im pretty sure they are both bad.
I actually bought 2 relays from The Last Detail- and im pretty sure they are both bad.
Ecklers replaced mine, no charge