blowing headlights
Thread Starter
Melting Slicks
Joined: Oct 2010
Posts: 2,276
Likes: 337
From: "ɹǝpunuʍop", Adelaide, South Australia
blowing headlights
a couple of months ago i placed relays in the '72 for the sealed beam headlights
light output was unbelievable for only 37.5/50w globes
info from on here and http://www.danielsternlighting.com/t...ys/relays.html and the following wiring diagram
mounted on the rail up the front just where the hoses come
20amp circuit breaker, main heavier + wire (top left) from alternator/horn relay
brown socket (top cntr) from left headlight supplies the trip for the relays
new loom, so the original has not been cut into, sockets disconnected taped up
shared heavy earth lead with ring terminal to a clean earth point
tan wires low, green wires high
2 separate runs as relays had double out pins, right run l/h is separate to left l/h run except earth
problem is that i keep blowing the left hand low beam headlight
have replaced 3 so far, they only last 30min max...
have good voltage at socket, either straight to the chassis or thru the socket.
no problem with the high beams.... yet
i am at a loss to why?
light output was unbelievable for only 37.5/50w globes
info from on here and http://www.danielsternlighting.com/t...ys/relays.html and the following wiring diagram
mounted on the rail up the front just where the hoses come
20amp circuit breaker, main heavier + wire (top left) from alternator/horn relay
brown socket (top cntr) from left headlight supplies the trip for the relays
new loom, so the original has not been cut into, sockets disconnected taped up
shared heavy earth lead with ring terminal to a clean earth point
tan wires low, green wires high
2 separate runs as relays had double out pins, right run l/h is separate to left l/h run except earth
problem is that i keep blowing the left hand low beam headlight
have replaced 3 so far, they only last 30min max...
have good voltage at socket, either straight to the chassis or thru the socket.
no problem with the high beams.... yet
i am at a loss to why?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
Are the relays 'solid state' or contactor type? If not solid state, you could be putting a lot of stress on the filaments from current spikes when the contactors close. Not sure why just one bulb, but I suspect the others may be short-lived, too. (Is the bulb that is burning out the nearest one to its feed line?)
Perhaps a spike-suppressing capacitor on both the 'low-beam" and "hi-beam" output lines would solve your problem.
Perhaps a spike-suppressing capacitor on both the 'low-beam" and "hi-beam" output lines would solve your problem.
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
this is out of daniel stern article, like 7t1vette said you may have spiking, may need to check your alternator V.Reg. output w/ a meter while turning headlights on. dont know where you're getting your supply voltage from but its just a thought. goodluck.
"You may have heard that it's not good to take headlamp power from the alternator output because of "voltage spikes"; this is a myth. No voltage spikes are present in an electrical system with good voltage regulation, and any spikes that are present in a system with bad voltage regulation are present in equal magnitude across the entire system. If your charging system is "spiky", indicated by vehicle lamps that flash brighter and dimmer with the engine running at a steady speed, then you need to fix the problem that is causing the spikes! "
"You may have heard that it's not good to take headlamp power from the alternator output because of "voltage spikes"; this is a myth. No voltage spikes are present in an electrical system with good voltage regulation, and any spikes that are present in a system with bad voltage regulation are present in equal magnitude across the entire system. If your charging system is "spiky", indicated by vehicle lamps that flash brighter and dimmer with the engine running at a steady speed, then you need to fix the problem that is causing the spikes! "
The ORIGINAL and bestest
Joined: Oct 2000
Posts: 10,009
Likes: 240
From: Toronto Ontario
Toronto Events Coordinator
Are the relays 'solid state' or contactor type? If not solid state, you could be putting a lot of stress on the filaments from current spikes when the contactors close. Not sure why just one bulb, but I suspect the others may be short-lived, too. (Is the bulb that is burning out the nearest one to its feed line?)
Perhaps a spike-suppressing capacitor on both the 'low-beam" and "hi-beam" output lines would solve your problem.
Perhaps a spike-suppressing capacitor on both the 'low-beam" and "hi-beam" output lines would solve your problem.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
...what kind of relay are you using?
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,356
From: Santa Ana CA
This would seem to be a problem of over voltage so check whats coming out of the alternator.
Last edited by toddalin; Feb 7, 2012 at 05:34 PM.
The ORIGINAL and bestest
Joined: Oct 2000
Posts: 10,009
Likes: 240
From: Toronto Ontario
Toronto Events Coordinator
I always use good relays, such as Bosch, or Tyco.
Some good tech here:
http://www.madelectrical.com/electri...adlights.shtml
And here:
http://www.danielsternlighting.com/t...ys/relays.html
Last edited by 7t2vette; Feb 7, 2012 at 05:44 PM.
Thread Starter
Melting Slicks
Joined: Oct 2010
Posts: 2,276
Likes: 337
From: "ɹǝpunuʍop", Adelaide, South Australia
Shark - using Narva relays http://www.narva.com.au/products/browse/normal-open-4-5
7t2 - thats where i got my info from and from on this forum
only difference to the wiring diagram above is that i have from the relay, 1 wire direct to the left and 1 wire direct to the right instead of as shown...
relay had 2 output terminals so i used both
maybe i should join them together ?
will get the alt output checked by an auto electrician
7t2 - thats where i got my info from and from on this forum
only difference to the wiring diagram above is that i have from the relay, 1 wire direct to the left and 1 wire direct to the right instead of as shown...
relay had 2 output terminals so i used both
maybe i should join them together ?
will get the alt output checked by an auto electrician
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Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
If your wiring is messed up and powering both the hi and low beam for the left light at the same time it will probably overheat and burn out quickly. Those relays have a normally open contact 87 and normally closed 87a. If you are using both it could be causing the problem.
The ORIGINAL and bestest
Joined: Oct 2000
Posts: 10,009
Likes: 240
From: Toronto Ontario
Toronto Events Coordinator
Your wiring diagram looks fine, should be no problem using both 87 terminals on the relays, they are afterall a common output. This is the relay you used?
First thing I would do is doublecheck your wiring, and then check your system voltage with a volt meter.
First thing I would do is doublecheck your wiring, and then check your system voltage with a volt meter.
Last edited by 7t2vette; Feb 7, 2012 at 06:52 PM.
Thread Starter
Melting Slicks
Joined: Oct 2010
Posts: 2,276
Likes: 337
From: "ɹǝpunuʍop", Adelaide, South Australia
UPDATE
i went to auto elec, and he said the alternator is fine, 14.2-14.4v under load.
if it was over voltage/spiking then other globes -blinkers, dash etc would be blowing as well.
the relay wiring i did checked out fine.
the only thing he commented on was the headlights open with a hard sudden stop.
there also aren't many makers of sealed beams any more, mainly cheap asian units,
which he thinks the filament is breaking with the hard stop now that it's got good voltage.
he suggested a few options,
1/ put a 3-5sec timer relay in so the doors open then the lamps light up
2/ tap into the door open switch to turn on relay only when fully up
3/ convert to halogen sealed beam (easy swap, more resilient)
4/ convert to halogen h4/h1 globes (harder swap)
how hard is the swap to option 4?
how much do the buckets/rear brace have to be opened up to fit the bigger back of the globe?
anyone got photo's? a link?
i went to auto elec, and he said the alternator is fine, 14.2-14.4v under load.
if it was over voltage/spiking then other globes -blinkers, dash etc would be blowing as well.
the relay wiring i did checked out fine.
the only thing he commented on was the headlights open with a hard sudden stop.
there also aren't many makers of sealed beams any more, mainly cheap asian units,
which he thinks the filament is breaking with the hard stop now that it's got good voltage.
he suggested a few options,
1/ put a 3-5sec timer relay in so the doors open then the lamps light up
2/ tap into the door open switch to turn on relay only when fully up
3/ convert to halogen sealed beam (easy swap, more resilient)
4/ convert to halogen h4/h1 globes (harder swap)
how hard is the swap to option 4?
how much do the buckets/rear brace have to be opened up to fit the bigger back of the globe?
anyone got photo's? a link?
Last edited by riverracer au; Feb 14, 2012 at 08:24 AM.
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
The H4 / H1 globes are a good options but I don't think they fit perfectly into the stock buckets and you would need to make room for the larger rear end of the globe by cutting the opening bigger in the backs of the buckets. Halogen would be your easiest solution. Next up would be the new housings, and to stay away from trying to overcomplicate the system with delays and limit switches.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
7t2Vette - I understand the concept of relays, voltage drop, etc. My language was wrong.
What I meant to say was that the system where the SWITCH feeds the headlights does not carry the same voltage to the headlights. Much different electrical load to the headlights with a relay system than in the original switch system due to the voltage drop of the wires.
I've long been a proponent of headlight relay upgrades on older cars. I converted my 83 Ford and it was a "night and day" (sigh) difference.
riverracer au-
Option 3, I used Sylvania halogens in my truck, they worked well.
Option 4 - A company called... talbotco? I believe, aardvark industries, sells a cibie kit that I have in my 78 that uses the H4 style bulb. Look them up. It was a bolt in for me. A search for "talbotco" shows them on the first page for me.
What I meant to say was that the system where the SWITCH feeds the headlights does not carry the same voltage to the headlights. Much different electrical load to the headlights with a relay system than in the original switch system due to the voltage drop of the wires.
I've long been a proponent of headlight relay upgrades on older cars. I converted my 83 Ford and it was a "night and day" (sigh) difference.
riverracer au-
Option 3, I used Sylvania halogens in my truck, they worked well.
Option 4 - A company called... talbotco? I believe, aardvark industries, sells a cibie kit that I have in my 78 that uses the H4 style bulb. Look them up. It was a bolt in for me. A search for "talbotco" shows them on the first page for me.
Last edited by Shark Racer; Feb 14, 2012 at 02:03 PM.
Thread Starter
Melting Slicks
Joined: Oct 2010
Posts: 2,276
Likes: 337
From: "ɹǝpunuʍop", Adelaide, South Australia
unfortunatly i need to buy australian approved globes/lens as our lights dip to the left
when we import cars over here, thats one of the first things they check
will try an get some sealed beam halogens first
thanks everyone
when we import cars over here, thats one of the first things they check
will try an get some sealed beam halogens first
thanks everyone
The ORIGINAL and bestest
Joined: Oct 2000
Posts: 10,009
Likes: 240
From: Toronto Ontario
Toronto Events Coordinator
These are the exact H4 & H1 light housings I have been using for years with SilverStar lamps. They fit the headlight buckets with no mods. The low beams are plug and play, the high beams I made a short pigtail with male spade connectors on the end to plug into the factory plug.
low beams:
http://www.ebay.ca/itm/5-3-4-4000-H5...item4cfb5679d0
high beams:
http://www.ebay.ca/itm/5-3-4-H5001-H...item3594f56598
On my bench
The pigtails almost finished on the high beams
On the car
Halogens on the left, H1 & H4 on the right
low beams:
http://www.ebay.ca/itm/5-3-4-4000-H5...item4cfb5679d0
high beams:
http://www.ebay.ca/itm/5-3-4-H5001-H...item3594f56598
On my bench
The pigtails almost finished on the high beams
On the car
Halogens on the left, H1 & H4 on the right
