Headlight relay hissing
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Headlight relay hissing
I'm asking for a little help with my head light relays as I appear to have a vacuum leak. I'd like to know if they need attention for my 82.
First the lights go up and down as they should but with the drivers side is a bit on the lazy side.
All the hoses have a good fit , but I noticed that both relays have a slight "hiss" coming from the bottom. This hiss is confirmed with a small hose in my ear and probing the end near the relays.
My guess is that it is not normal to have the hiss and really unusual to have both sides?
So, is this something that I should just leave alone--- after all the lights do go up and down, just not in unison or very quickly? Or can the relays be rebuilt so they hold total vacuum or am I resigned to buy two new ones?
Thanks!
First the lights go up and down as they should but with the drivers side is a bit on the lazy side.
All the hoses have a good fit , but I noticed that both relays have a slight "hiss" coming from the bottom. This hiss is confirmed with a small hose in my ear and probing the end near the relays.
My guess is that it is not normal to have the hiss and really unusual to have both sides?
So, is this something that I should just leave alone--- after all the lights do go up and down, just not in unison or very quickly? Or can the relays be rebuilt so they hold total vacuum or am I resigned to buy two new ones?
Thanks!
Team Owner
Joined: Sep 2006
Posts: 31,267
Likes: 4,362
From: Westminster Maryland
Hi b,
If you decide to replace your relays (I'd first try to determine where exactly the 'hiss' is to be certain you need to spend the money) be sure to buy them from a reliable source since too often the new relays available today don't work, or prove to be unreliable.
Perhaps Willcox?
Regards,
Alan
If you decide to replace your relays (I'd first try to determine where exactly the 'hiss' is to be certain you need to spend the money) be sure to buy them from a reliable source since too often the new relays available today don't work, or prove to be unreliable.
Perhaps Willcox?
Regards,
Alan
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
So the suggestion is take it apart and rebuild? I'm reasonably handy and like to do a bit of research before unbolting things (I've make enough mistakes) I've looked for a few tutorials and have come up short... is this pretty straight forward?
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
The relays will make a sound when the vacuumed hose is vented to atmosphere during it's duty cycle, but not for very long. If what you are hearing is for more than a couple of seconds, you have a vacuum leak. Both actuating positions inside the relay chamber vent to the bottom of the relay.
Rather than go into a long explanation of why the newer relays fail, I will just offer this. If your relays are indeed original GM (AC SPARK PLUG DIV molded into the plastic base), and the top control chamber holds vacuum (most do, easy to check) I can rebuild them for you for just the cost of postage back to you. I do not rebuild the non GM relays for many reasons. PM if interested
Rather than go into a long explanation of why the newer relays fail, I will just offer this. If your relays are indeed original GM (AC SPARK PLUG DIV molded into the plastic base), and the top control chamber holds vacuum (most do, easy to check) I can rebuild them for you for just the cost of postage back to you. I do not rebuild the non GM relays for many reasons. PM if interested
Last edited by Dave J; Aug 20, 2016 at 10:08 AM. Reason: posted too soon
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
I just checked the price on a genuine GM relay. $94 and some change for one.
Rebuilt them and sold them
You're right, $94!?
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From: Seattle Area Washington
The relays will make a sound when the vacuumed hose is vented to atmosphere during it's duty cycle, but not for very long. If what you are hearing is for more than a couple of seconds, you have a vacuum leak. Both actuating positions inside the relay chamber vent to the bottom of the relay.
Rather than go into a long explanation of why the newer relays fail, I will just offer this. If your relays are indeed original GM (AC SPARK PLUG DIV molded into the plastic base), and the top control chamber holds vacuum (most do, easy to check) I can rebuild them for you for just the cost of postage back to you. I do not rebuild the non GM relays for many reasons. PM if interested
Rather than go into a long explanation of why the newer relays fail, I will just offer this. If your relays are indeed original GM (AC SPARK PLUG DIV molded into the plastic base), and the top control chamber holds vacuum (most do, easy to check) I can rebuild them for you for just the cost of postage back to you. I do not rebuild the non GM relays for many reasons. PM if interested
Last edited by bmotojoe; Aug 20, 2016 at 11:26 AM.
