Sealed beam headlight help

[firerod]

I rewired my old harness to accept three prong sealed beam lights. I cut the wire that fed the park lights and made that my ground (grounded to frame). When I use a test light everything seems to work as it should, then when I plug the light bulb in the headlights don't work and my test light shows all prongs including the ground hot. The taillight works fine. Still using a 6 volt positive ground system and switch in the steering column. Any ideas?

[DHZIEMAN]

Originally Posted by firerod

I rewired my old harness to accept three prong sealed beam lights. I cut the wire that fed the park lights and made that my ground (grounded to frame). When I use a test light everything seems to work as it should, then when I plug the light bulb in the headlights don't work and my test light shows all prongs including the ground hot. The taillight works fine. Still using a 6 volt positive ground system and switch in the steering column. Any ideas?

First off, not enough info but..........
Check the sealed beams connected to a 6 volt source to assure they are good! both low and high beam. If you are getting power at the connector and the sealed beams still don't light, then either the plugs are mis-wired or the sealed beams are defective. Let us all know.

[katy]

It sounds like your "ground" isn't connecting to B+ (ground) properly

[Dick M]

Run your ground wire from the screw in the headlight bucket, the one used to adjust the stock bulb, to the frame. You can use the screw for the front hood hold down for the connection at the frame. The ground wire can be attached inside the bucket and run through the conduit and down to the frame. Make sure your connections are clean and free of rust or paint. You will then have a direct ground.

[Jim Brierley]

Somewhat related, the stock generator will not keep up with sealed beams without throwing solder. Use a later generator or alternator if driving at night very much.

[firerod]

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Thank you for the help. I retraced all my wires and found a bad ground. All works good now. I try not to drive at night but get caught out once in a while on my way home. Do I need a fuse or relay? I had my generator rebuilt approx. 1500 miles ago, will it be ok? How do I tell if I have a early or late generator?

[chap52]

I was going to suggest that you disconnect your ground wire from the plug and jump a "known good ground" wire and test the lights. Just had a similar issue with the right sealed beam not as bright as the left. That test pinpointed the issue and the correct ground was redone.
Glad you figured it out. Thanks for the update. Chap

[DHZIEMAN]

The 6 volt halogens (all you can get any more) have a heavy draw on current. So, if there is any extensive night driving, then for an original 3 brush Ford Generator, it has to be cranked up to handle the increased current. But then in attempting to balance against daylight driving, if not cranked back down a bit, the generator will boil the battery by overcharging. As I had gotten into this situation, I bit the expensive bullet and replaced the 3 Brush Gen with a modified 6 V Alternator and all is well.

[Badpuppy]

Originally Posted by Jim Brierley

Somewhat related, the stock generator will not keep up with sealed beams without throwing solder. Use a later generator or alternator if driving at night very much.

The standard 6006 bulb consumes 50/40 watts, the H6006 halogen type bulb 60/55. 60W translates to 10A per bulb @ 6V. Since the stock generator is rated at 12A output, it will obviously be overloaded, even when running standard bulbs on low beam. An alternator should be in your future if you intend to do much night driving. That being said, an overloaded generator takes a while before it melts, so you might get by with only very short trips.

[Bill Pursel]

Originally Posted by firerod

I rewired my old harness to accept three prong sealed beam lights. I cut the wire that fed the park lights and made that my ground (grounded to frame). When I use a test light everything seems to work as it should, then when I plug the light bulb in the headlights don't work and my test light shows all prongs including the ground hot. The taillight works fine. Still using a 6 volt positive ground system and switch in the steering column. Any ideas?

If your ground is hot then you have a bad ground.