Fog light issues

jacob smith

jacob smith

Senior Member
I wired up my fog lights on my 36 ford using a 6 volt VW relay. I used the attached wiring diagram. The light work great.

https://www.fordbarn.com/attachments/245868/

Issue is that my genorator does not keep up when the spot lights are on. Before I installed the fog lights when driving the needle on the gauge was 1/2 way between 0 and the top. When you would put the headlights on the needle would be just a little above 0. As soon as the spot light turn on the needle drops 1/2 way below 0 and the bottom of the gauge.

Any ideas what to do to correct this

Jacob
 
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The relay was a good move in that it allows the large amount of current needed to illuminate your spot lights, but without that current going through some "wimpy", little switch not up to the task of carrying the load.

The problem you have now is that your generator seems not rated to supply the amount of amperage (current) that these additional lights are requiring. DD
 
Im not sure what bulbs you have but with an original generator its close to max with 4 headlight bulbs.
Make sure the belt is fresh and tensioned correctly so it dont slip to.
 
Jacob, What generator do you have on your 1936 Ford ? If it is the original third brush unit with the round cut out mounted on top then it is only capable of about 15 amps safe maximum and NO more. This is not enough to cover headlights + fog lights + tail and dash lights + ignition. If you set the third brush inside the generator at the maximum of 15 amps and then drive the car during the day with the lights OFF then that 15 amps (less the ignition 3 amps ) will all go into the battery and overcharge and overheat it on anything more than a 15 minute drive. There is no regulation in that charging system to compensate for varying battery condition or loads (lights etc) turned on or off. That's the design of that early charging system. Up grades are possible with later model generators fitted with voltage regulators or alternators but these change the car from original. My opinion keep the fog lights for show only and set your third brush in the generator for a maximum charge on your dash ammeter of 5 amps with your lights off for daytime driving. You will have to set the third brush up to about 15 amps if you do mainly night driving. Regards, Kevin.
 
Kevin
Yes I have the the original 3 brush genorator with the round cut out. I do not drive that much at night but when I do I wanted the fog light to help light up the road. I do not want to up grade to a later style but if that is what is need to make it so I have good lights at night maybe that is what I will have to do.
 
As long as the amp meter is showing "0" or a little above, it may not be that much of an issue. A discharge (-) reading would be more of a concern. I would drive it for a while and see what the results are. As long as your not driving for hours at night with the fog lights on not sure it's a problem.

By the way, that was my diagram, glade it helped you out.
 
I have the same problem with my clear lens fog lights. At 1st I worried but the nights driving back from shows I seem to always have enough batter
y to get me home. Ido turn off the fog lights if on a lighted road. Enjoy your rides!
 
Jseery
Yes that wiring diagram was great, next I am looking at doing my headlights with the same set up. When I turn on my fog lights I drop in to the -15 range
Ken
I was looking at photos of your car and wondering if you had the same issue. Thanks for the reply

Has anyone seen a set up like this

http://www.fordgarage.com/pages/generator.htm

They says it is for an A. But maybe it can also be set up for my 36. I also read this for a
Chevy

http://www.1928chevrolet.com/articles/voltreg.html

Anyone seen this done
 
you can use a "fun projects" regulator instead of the cut out. then, set your gen at higher output for when you need it, and regulated low automatically when you dont. they look identical, 12 volt or 6, pos or neg ground, google it up..fun projects
 
jacob smith said:
Jseery
Yes that wiring diagram was great, next I am looking at doing my headlights with the same set up. When I turn on my fog lights I drop in to the -15 range
Click to expand...

-15 is a different issue! It is discharging your battery, as I am sure you know. It is just a matter of how much discharge the battery will take.
 
Jacob, You can fit the Fun Projects round regulator in place of the original cut out on top of your generator. This will compensate for loads ( lights) turned off and on and also the condition of the battery to a point. With this fitted you can then adjust the generator third brush setting up to a maximum of 15 amps. If you go higher than 15 amps then there is a big possibility of the generator armature overheating and burning out. An output maximum of 15 amps on a 6 volt system still will not cover fully the current draw of 2 headlamps + two tail lights + 2 dash lights + 2 fog lights + Ignition system. Depending on which power headlight and fog light bulbs you have fitted your total current demand would be at least 25 amps. Your dash ammeter will never sit on "0" or a + charge with all those items turned on. As I said be very careful you don't set that generator above 15 amps. You could however use your fog lights for a half hour or so at night with your ammeter showing a negative 10 amps and the battery would handle that if it is good. However your voltage would be down somewhat because of no charge going into the battery. With the voltage down your lights would be somewhat dimmer. Your original 1936 Ford generating system was just not designed for these extra loads, Its as simple as that. Regards, Kevin.
 
jacob smith said:
Jseery
Yes that wiring diagram was great, next I am looking at doing my headlights with the same set up. When I turn on my fog lights I drop in to the -15 range
Ken
I was looking at photos of your car and wondering if you had the same issue. Thanks for the reply

Has anyone seen a set up like this

http://www.fordgarage.com/pages/generator.htm

They says it is for an A. But maybe it can also be set up for my 36. I also read this for a
Chevy

http://www.1928chevrolet.com/articles/voltreg.html

Anyone seen this done
Click to expand...

i used one of these regulators on my `37 1/2 ton, best thing i ever did to the truck. well worth the money!
tom
 
Kevin
Thank you for the better understanding. I think that I will give the fun product a try with this understanding in hopes that I will be able to get a little more out of the system. Along with all that other stuff I still have to run the radio too.
 
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