Headlight door vacuum relays
Thread Starter
5th Gear
Joined: Aug 2020
Posts: 5
Likes: 0
Headlight door vacuum relays
Having trouble getting the headlight doors to open and close reliably on 1970 with twin relays.
Engine makes 12" vac but only delivers 2" to actuators.
I can bypass wiper system and tank but get the same result.
Switch signal is 10" at relay with lights off I assume thats fine.
Hoses are fine.
12" vacuum when delivered direct to individual actuators front or back ports will slam the doors open or closed.
Could the relays (original parts) be causing the loss of vacuum?
Engine makes 12" vac but only delivers 2" to actuators.
I can bypass wiper system and tank but get the same result.
Switch signal is 10" at relay with lights off I assume thats fine.
Hoses are fine.
12" vacuum when delivered direct to individual actuators front or back ports will slam the doors open or closed.
Could the relays (original parts) be causing the loss of vacuum?
Race Director
Joined: Apr 2011
Posts: 11,183
Likes: 3,335
From: North of Toronto - Ontario
The "dog-bones" that move inside the relays are probably dry/shrunk and leaking (which is kind of normal)
I was chasing a small vacuum leak and noticed mine were leaking a month or so ago so I cheated and poured brake fluid into them (on the bench of course) and soaked overnight to soften/swell up the rubber seals on them and that worked out (who knows for how long...) there is a couple of real solutions that involve getting them out and putting o-rings on them for a more permanent solution.
The reproduction relays seem to be not the best quality or at least some people are having problems with them
M
https://www.corvetteforum.com/forums...-valves-2.html
I was chasing a small vacuum leak and noticed mine were leaking a month or so ago so I cheated and poured brake fluid into them (on the bench of course) and soaked overnight to soften/swell up the rubber seals on them and that worked out (who knows for how long...) there is a couple of real solutions that involve getting them out and putting o-rings on them for a more permanent solution.
The reproduction relays seem to be not the best quality or at least some people are having problems with them
M
https://www.corvetteforum.com/forums...-valves-2.html
Last edited by Mooser; Aug 9, 2021 at 10:30 AM.
