Help Troubleshooter Headlight problem
Thread Starter
Racer
Joined: Nov 2009
Posts: 489
Likes: 1
From: Suffolk Virginia
Okay...
It popped right up when I ran the hose straight from the tank to the acuator.
When I run it through the relay the left raises an inch or so. falls slightly, then raises after the right is up all the way. I consider both side lazy. Sounds like the relay?
It popped right up when I ran the hose straight from the tank to the acuator.
When I run it through the relay the left raises an inch or so. falls slightly, then raises after the right is up all the way. I consider both side lazy. Sounds like the relay?
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
hum... If you car was in my shop, I'd install a test relay we keep around. If the symptoms were the same I'd go to the actuator. In this case I still think since the relay is working the right lamp... that you have an issue with the shaft seal on the actuator or a crack in the diaphragm. At this point I don' think the relay is the issue.
I think speed mentioned above put a vacuum pump on the actuator.. see if it's leaking...
I think speed mentioned above put a vacuum pump on the actuator.. see if it's leaking...
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
The vacuum relays have one small hose going to a diaphram on top which controls the relay. I've never seen or heard of a leak there. On the body of the relay there are three large hose nipples. The center nipple is the supply connection, top and bottom nipples are for open and close. Connect a vacuum pump to the center nipple, plug either the top or bottom nipple (one is expected to be open, the other should be closed), see if you can hold a vacuum. If you need to plug BOTH top and bottom nipples to hold a vacuum, your seals are leaking.
There was a thread on this forum last fall regarding attempts to rebuild the vacuum relays. There are a two seals, cup shaped, which dry out over the years, seal poorly. I tried to save mine but finally gave in and bought new ones. Simple design...
Intermediate
Joined: Mar 2004
Posts: 26
Likes: 0
From: Ojai CA
You might also want to look at:
http://www.zip-corvette.com/ProductD...GR-SR&CTitle=&
It includes the locking ring should the old one's locking ears break (can you imagine!)
http://www.zip-corvette.com/ProductD...GR-SR&CTitle=&
It includes the locking ring should the old one's locking ears break (can you imagine!)
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Thread Starter
Racer
Joined: Nov 2009
Posts: 489
Likes: 1
From: Suffolk Virginia
UPDATE:
Installed new actuators, lights are coming up even slower now.
I can't think of anything I did that would make things worse. I did discover a missing spring on the left side. I borrowed on from the right but it didn't help.
I guess I'll replace the relay and hoses next... what's another $100 into the pit?
- Jay
Installed new actuators, lights are coming up even slower now.
I can't think of anything I did that would make things worse. I did discover a missing spring on the left side. I borrowed on from the right but it didn't help.
I guess I'll replace the relay and hoses next... what's another $100 into the pit?
- Jay
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The relays are your problem. The test of directly putting vacuum on the servos and having the light come up OK proved that. The sealing lips on the shuttle valves in the relays are worn away and don't seal well, anymore.
If you want to test this before you throw money at it, pull the YELLOW hose off the relay(s) and just shoot a little white lithium grease (spray can) down into it. That will make an artificial improvement in sealing capability for a few cycles. If the headlights then work somewhat faster, then you know that's the problem.
I'm afraid I don't understand the logic for repairing/replacing the actuators when direct vacuum showed they worked fine.....
If you want to test this before you throw money at it, pull the YELLOW hose off the relay(s) and just shoot a little white lithium grease (spray can) down into it. That will make an artificial improvement in sealing capability for a few cycles. If the headlights then work somewhat faster, then you know that's the problem.
I'm afraid I don't understand the logic for repairing/replacing the actuators when direct vacuum showed they worked fine.....
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
I had exactly the same problem as I mentioned earlier. The first culprit people suggested was the actuators. If they'll hold vacuum, pop the headlights up or pull them down, they're OK. I actually took one apart. There's not much to them. A diaphragm with a shaft attached, vacuum applied to one side or the other.
For me, it turned out ALL three vacuum relays were leaking, two for headlights and one for the wiper door.
The vacuum relays would be my next bet in your case, assuming there are no other mass vacuum leaks from hoses or the vacuum tank.
For me, it turned out ALL three vacuum relays were leaking, two for headlights and one for the wiper door.
The vacuum relays would be my next bet in your case, assuming there are no other mass vacuum leaks from hoses or the vacuum tank.
Thread Starter
Racer
Joined: Nov 2009
Posts: 489
Likes: 1
From: Suffolk Virginia
Since I only have one relay anyway (for whatever reason), I'll get at least one more, plus a new hose kit. Even if that's not the problem I might as well have new stuff so I wont have to go throught this again any time soon.
Race Director
Joined: Jan 2002
Posts: 11,614
Likes: 350
From: No Where USA
UPDATE:
Installed new actuators, lights are coming up even slower now.
I can't think of anything I did that would make things worse. I did discover a missing spring on the left side. I borrowed on from the right but it didn't help.
I guess I'll replace the relay and hoses next... what's another $100 into the pit?
- Jay
Installed new actuators, lights are coming up even slower now.
I can't think of anything I did that would make things worse. I did discover a missing spring on the left side. I borrowed on from the right but it didn't help.
I guess I'll replace the relay and hoses next... what's another $100 into the pit?
- Jay
Like I said before, you should just replace everything. You are going to do it anyway. That way you won't spend hours trying to figure out what is wrong. Then fix it only to have the next thing break.
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
I agree, just buy everything and be done with it.
I tried replacing the seal in the actuator and when you unbend the 3 tabs and try to bend them back at least 1 tabs breaks and the actuator fails again in short order.
I tried new "O" rings in the relay, I couldn't peal back the top so I cut it off, good luck getting that back on.
The hoses were fine and I just cut them back a bit for a good seal.
But it puts a smile on my face now that they work OK.
I tried replacing the seal in the actuator and when you unbend the 3 tabs and try to bend them back at least 1 tabs breaks and the actuator fails again in short order.
I tried new "O" rings in the relay, I couldn't peal back the top so I cut it off, good luck getting that back on.
The hoses were fine and I just cut them back a bit for a good seal.
But it puts a smile on my face now that they work OK.
Thread Starter
Racer
Joined: Nov 2009
Posts: 489
Likes: 1
From: Suffolk Virginia
WHOOOOHOOOO!
Got my new relays today, hoses didn't show up yet.
Hooked up a new relay and BAM! BAM! Lights jumped up like nobody's busness. Still have a little work to do, but its nice to have something go right finally.
Thanks for all the help everybody!
Got my new relays today, hoses didn't show up yet.
Hooked up a new relay and BAM! BAM! Lights jumped up like nobody's busness. Still have a little work to do, but its nice to have something go right finally.
Thanks for all the help everybody!
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Well done! I love a happy ending. I know it put a smile on your face when they popped up!