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| | | Joined: Jul 2010 Posts: 89 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2010 Posts: 89 | truck i bought dosent seem to have a relay for headlights.
is one ness?
what's the downside?
it ain't YOURS 'till it ain't stock!
1951 chevy 3100
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
What year?
What type of bulbs?
6v or 12v?
Original gauge wire?
If all original, and there was no relay originally, none is necessary. There has been no downside that I am aware of on my 6v 47-55 trucks with original wiring and bulbs.
However, some people add them, even in original systems.
If you are using higher-power bulbs than the originals, a relay might be beneficial (in time, material, and safety) if you have to re-wire.
| | | | | Joined: Sep 2008 Posts: 137 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2008 Posts: 137 | In general, the purpose of using the relay is to shorten the circuit from the battery to the headlights (and maybe to use heavier gauge wire). The idea is that there will be less resistance resulting in more power delivered to the lights (i.e. brighter lights).
They aren't necessary, by any means, just one of those "upgrades" that some people do. My '54 has an original-style harness and I think my headlights are plenty bright. | | | | | Joined: Jul 2010 Posts: 89 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2010 Posts: 89 | Sorry keep forgettin'
halogen bulbs -12v
12ga wire
early 70's chevy altenator/sb350
was wondering if it's too much draw on the headlight switch
it ain't YOURS 'till it ain't stock!
1951 chevy 3100
| | | | | Joined: Sep 2008 Posts: 137 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2008 Posts: 137 | That's exactly how mine is set up and no problems here. Lights are plenty bright. I have a brand new wiring harness (i.e. new wires and new connectors), so that might make a difference.
Last edited by chicklin; 08/25/2010 3:29 PM.
| | | | | Joined: Jul 2010 Posts: 89 Wrench Fetcher | | Wrench Fetcher Joined: Jul 2010 Posts: 89 | my harness is new as well.
guess i'll try swapping bulbs to check for bad connection causing dim headlight (still dim prob wiring?) or a dim bulb.
it ain't YOURS 'till it ain't stock!
1951 chevy 3100
| | | | | Joined: Sep 2008 Posts: 137 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2008 Posts: 137 | Every dim light problem I have ever had was bad grounds. | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | Most light problems period are bad grounds. | | | | | Joined: Feb 2004 Posts: 29,771 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,771 | A relay will keep the load off the headlight switch and possibly make the lights brighter, but two relays, one each for high and low beam, triggered by the dimmer switch, will protect both switches. I've found that dimmers are much more prone to failure than dash switches.
Jerry
Last edited by Hotrod Lincoln; 08/28/2010 5:37 PM.
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| | | | | Joined: Nov 2008 Posts: 544 Shop Shark | | Shop Shark Joined: Nov 2008 Posts: 544 | A schematic of how all this ties together - lights to relay to switches/dimmers. I know the mad electrical relay wiring, but something that is specific to that particular application for those of us who are auto wiring deficient. | | |
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