Single Headlight Relay?
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Single Headlight Relay?
Did we decide, during those few headlight threads, that both headlight actuators could be operated by a single relay? The reason I ask is simplicity. Both of my relays were shot, and Sully was real cool about sending me a pair of used ones totally free. Awesome guy by the way.
Anyway, I was installing them, and testing them, and while they work great now the headlights still go up inconsistently with one another.
Would a single relay, with 'T's in the lines going to the two actuators, make the system a little more uniform? Would the single relay even be able to control the two actuators properly?
Anyway, I was installing them, and testing them, and while they work great now the headlights still go up inconsistently with one another.
Would a single relay, with 'T's in the lines going to the two actuators, make the system a little more uniform? Would the single relay even be able to control the two actuators properly?
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
Single relay should be able to handle both lights. Just need a few T's and you should be golden. I have often thought about doing this to mine just to simplify and see if both headlights will work better. The good thing about it is, you can try each relay and pick the one that makes the lights work better.
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
Matt I reread your OP and I see you dont like that they dont go up even.Thats probably why GM went to 2 relays.
I have played with restricting the vacuum using a valve on the fastest one to try and slow it down.It was real touchy and inconsistant.I had better luck trying to make the resistance of the mechanical mechanism in each headlight more equal.But I only did this by putting my hands on them and restricting them from opening.If this is a big concern I'm sure you could build some kind of a thumbscrew type of adjustable brake to put on the over center mechanism to make each light have enough resistance to make them open equally.
The 69 I just finished putting relays in and tightening up the lines only has a split second difference between the two.And dont get your fingers near the wiper door unless you want to lose one of them.
I have played with restricting the vacuum using a valve on the fastest one to try and slow it down.It was real touchy and inconsistant.I had better luck trying to make the resistance of the mechanical mechanism in each headlight more equal.But I only did this by putting my hands on them and restricting them from opening.If this is a big concern I'm sure you could build some kind of a thumbscrew type of adjustable brake to put on the over center mechanism to make each light have enough resistance to make them open equally.
The 69 I just finished putting relays in and tightening up the lines only has a split second difference between the two.And dont get your fingers near the wiper door unless you want to lose one of them.
Drifting
Joined: Jan 2004
Posts: 1,991
Likes: 3
From: Piscataway NJ
The only down side to one relay is if it goes you have nothing. Probably why they went to two. But you can always lift them up if either system fails. I have yet to see a vacuum system raise both lamps at the same time. Electric systems I have. And really does it matter that they both go up at the same millisecond?
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Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Actually, they both go up perfectly, but the passenger side drops slower, about five seconds later than the driver's side...and that I don't like.
I will get some 'T's and see if that closes the gap a little upon closing. If not, I will go back to two relays.
I will get some 'T's and see if that closes the gap a little upon closing. If not, I will go back to two relays.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
OH ok I didnt realize you were still using 2 relays when one didnt go down as fast.Try cleaning the slow relay.The problem might be on the green port side..that side has to dump vacuum from the front side of the actuator through a small passage in the relay and pull air in through that little piece of foam at the bottom of the relay.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I bought two large 'T's and a cap. I removed one of the relays, replaced the lines on the passenger side with new longer lines, and 'T'ed them into the other two. I just capped the vacuum tank port for the removed relay. If the single port from the other relay won't be enough I will uncap it and tap it into the other line.
I'll test it this afternoon to make sure it all works okay and we'll see if there is an improvement.
I'll test it this afternoon to make sure it all works okay and we'll see if there is an improvement.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
They go up at the same time, but the passenger side goes down a while after the driver's side does and it means that if I get somewhere at night I have to turn off the lights and sit there for 20 seconds or so until the other light drops so I can shut off the car.
Race Director
Joined: May 2006
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From: Dayton, Ohio
I bought two large 'T's and a cap. I removed one of the relays, replaced the lines on the passenger side with new longer lines, and 'T'ed them into the other two. I just capped the vacuum tank port for the removed relay. If the single port from the other relay won't be enough I will uncap it and tap it into the other line.
I'll test it this afternoon to make sure it all works okay and we'll see if there is an improvement.
I'll test it this afternoon to make sure it all works okay and we'll see if there is an improvement.
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Thread Starter
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
