Headlight Relay from The Last Detail Help!
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Headlight Relay from The Last Detail Help!
Has anyone else purchased the Repro headlight relays from The Last Detail? I think they have a design flaw and wanted to see if anyone else had trouble with them.
The troubleshooting guide says the closed circuit should hold vacuum when activated. This makes sense because the tank would bleed down if it didn't.
When I tested the new relays I just received:
The headlight open circuit holds vacuum
(green - no vac to white lines)
The headlight closed circuit does not hold vacuum
(red - vac to white lines)
Both of the relays work the same way. It makes no sense to me that they would sell something that is flawed from the start. For those who have replaced them, who did you purchase them from?
Any input is appreciated.
Jeff
The troubleshooting guide says the closed circuit should hold vacuum when activated. This makes sense because the tank would bleed down if it didn't.
When I tested the new relays I just received:
The headlight open circuit holds vacuum
(green - no vac to white lines)
The headlight closed circuit does not hold vacuum
(red - vac to white lines)
Both of the relays work the same way. It makes no sense to me that they would sell something that is flawed from the start. For those who have replaced them, who did you purchase them from?
Any input is appreciated.
Jeff
Racer
Joined: Jan 2005
Posts: 307
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From: River Bend NC
Just finished rebuilding my vacuum system
I finally got tired of all the squirelly stuff that my headlights were doing and rebuilt the whole mess. New lines, new switches, new headlight switch, new actuator kits. Of three NEW vacuum switches I recieved from Corvette America....two were faulty. I gave up on a dual switch system and t'eed both actuators off my one good switch.
So...there are bad parts out there from new supply. It's a b***ch though going back over and over work you've already completed...to locate a leak.
jd
So...there are bad parts out there from new supply. It's a b***ch though going back over and over work you've already completed...to locate a leak.
jd
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I have the new relays on my bench. I have the red and green ports capped. I am applying vacuum to the yellow center port.
With no vaccum to the pot (white port) The green (open) circuit is activated. I pull vacuum and it holds. When I apply vacuum to the pot, the red (closed) circuit is activated. I pull vacuum and it sucks air. I suspected that the valve was being pulled to far up causing a leak at the top end. I stepped the vacuum to the pot down gradually and continued to pull vacuum to the yellow port. Neither relay ever stopped sucking air. I know the rubber valve is good because it seals on one end. I am wondering if there is a void in the plastic at the top end that won't let it seal?
Jeff
With no vaccum to the pot (white port) The green (open) circuit is activated. I pull vacuum and it holds. When I apply vacuum to the pot, the red (closed) circuit is activated. I pull vacuum and it sucks air. I suspected that the valve was being pulled to far up causing a leak at the top end. I stepped the vacuum to the pot down gradually and continued to pull vacuum to the yellow port. Neither relay ever stopped sucking air. I know the rubber valve is good because it seals on one end. I am wondering if there is a void in the plastic at the top end that won't let it seal?
Jeff
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Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by ragtop73
I have the new relays on my bench. I have the red and green ports capped. I am applying vacuum to the yellow center port.
With no vaccum to the pot (white port) The green (open) circuit is activated. I pull vacuum and it holds. When I apply vacuum to the pot, the red (closed) circuit is activated. I pull vacuum and it sucks air. I suspected that the valve was being pulled to far up causing a leak at the top end. I stepped the vacuum to the pot down gradually and continued to pull vacuum to the yellow port. Neither relay ever stopped sucking air. I know the rubber valve is good because it seals on one end. I am wondering if there is a void in the plastic at the top end that won't let it seal?
Jeff
With no vaccum to the pot (white port) The green (open) circuit is activated. I pull vacuum and it holds. When I apply vacuum to the pot, the red (closed) circuit is activated. I pull vacuum and it sucks air. I suspected that the valve was being pulled to far up causing a leak at the top end. I stepped the vacuum to the pot down gradually and continued to pull vacuum to the yellow port. Neither relay ever stopped sucking air. I know the rubber valve is good because it seals on one end. I am wondering if there is a void in the plastic at the top end that won't let it seal?
Jeff
what is the amount of vacuum you are testing this with? is it over 15"?
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Last edited by bobs77vet; Mar 19, 2005 at 11:33 PM.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
all right i'm calling it quits for the night, i think you may be on the right track when you are thinking that you may have applied too much vacuum to the white pot....i bet the amount of vacuum that gets to that "white port" is significantly lower than whats in the "yellow port" . the white line is routed through out the car in a narrow tube and then is finally split at the relays .....i bet on a working car its really low vacuum reading if you were to measure it compared to the yellow line.
Racer
Joined: Jan 2005
Posts: 307
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From: River Bend NC
vacuum
I used a vacuum pump when troubleshooting my system (borrowed it from the local vette shop)....set it at 15 pounds. Everything worked great after I stopped the leaks. When running, my engine pulls 20 pounds.
Another wierd thing I found....someone (the previous owner I suspect) had turned the filter around at the port. This gave me another little fit figuring that out. What that does, since it's directional....headlights go up and down like they're supposed to, then creep open again with the lights off and engine running.
After hours of thinking and working on my vacuum system...when I finally got all the bugs out and got it working like it should...I actually did a little dance in the garage! Must've looked like some kinda rain dance to the neighbors.....cause it rained.
Another wierd thing I found....someone (the previous owner I suspect) had turned the filter around at the port. This gave me another little fit figuring that out. What that does, since it's directional....headlights go up and down like they're supposed to, then creep open again with the lights off and engine running.
After hours of thinking and working on my vacuum system...when I finally got all the bugs out and got it working like it should...I actually did a little dance in the garage! Must've looked like some kinda rain dance to the neighbors.....cause it rained.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by jdwhealton
After hours of thinking and working on my vacuum system...when I finally got all the bugs out and got it working like it should...I actually did a little dance in the garage! Must've looked like some kinda rain dance to the neighbors.....cause it rained.
they already know you are nuts.....good job, In a running car i bet you don't have 15" at the two "white pots"
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I went back and retested both relays. The rubber valve reaches its maximum travel at 5" of vacuum. If the problem was that the valve is traveling to far, then this is definately a design flaw.
Bob and JD, thanks for the input. I'll be sending these things back ASAP and reordering from someone else.
Thanks again,
Jeff
Bob and JD, thanks for the input. I'll be sending these things back ASAP and reordering from someone else.
Thanks again,
Jeff
