Electrical grounding to the frame

[pflaming]

I had my rear tail and turning lights attached up at the firewall so I would not have to run back and see if they were on / off. Today I mounted them in the back on the bed, nothing worked.

After a morning of frustration, a fellow from down the street wanders by. He knows all about electrical. After a review of my truck he said the lights must not be grounded, I thought they were, after all they were attached to the bed. Well. . . you know the rest, we put a good ground from the frame to the bed and we had lights!

What I learned was that the frame is essentially a hugh wire that completes the circle back to the battery so with the battery grounded to the frame then that becomes a common source for grounding back to the battery. Did not understand that, not stupid, just uninformed. Now I know why some put a ground from the bed and from the cab on these old trucks. Shakespeare was never this difficult, but this is a great hobby.

Doghouse comes off tomorrow, then back to the engine.

[greg g]

Had that same situation when I wired up my Studebaker recently. I bench tested the lamps before I installed them, wired them up and no joy. Made a jumper wire and conected a fixture to the frame and let there be light. Between the new paint on the frame and the paint on the underside of the bed, apparently there was not a good ground. Also might want to run a wire fromt he firewall to the frame also. Can't hurt and with 6V it is sure to help.

[pflaming]

Received "Classic Trucks" mag today. Noted they did not have a dual set of lights on the bed. I think that looks better than 'dualies'. Do I need to get different insides for my stock lights to do that. Seems I need triple filament bulbs and three wires. Is that correct?

I took all wires to a terminal strip so it will be easy to add and match, didn't like the looks of wire nuts and etc.

[MBF]

Pat-whether or not use you separate stop/turn and tail lights is dependant on which type of turn signal switch that you're using. The 5 wire switch runs the turn signals independantly and requires the use of lights that are added to the vehicle. The 7 wire turn signal switch, allows you to route the turn signal wiring through the brakelight switch and in effect uses the existing brake and tail lamp assemblies on the vehicle-so you don't need to mount or add lights on the rear to have turn signals. I'm not aware of any 3 filament bulbs or what they'd be used for. Just my ramblings......

[4852dodge]

Our truck beds are bolted to the frame through the wood of the bed. No metal to metal contact. You need to ground the lights to the frame with a ground wire or ground the steel bed to the frame. Later trucks used a steel floor and they were the ground.

[Merle Coggins]

My bed has a couple of brackets that attach between the sides and the frame near the back that would help ground the bed. But I still ran a ground wire for each tail light back to the frame.

Merle

[pflaming]

" . . .The 7 wire turn signal switch, allows you to route the turn signal wiring through the brakelight switch and in effect uses the existing brake and tail lamp assemblies on the vehicle-so you don't need to mount or add lights on the rear to have turn signals."

I have a seven wire switch, so back to the schematics. Thanks! My bed has the straps to the frame also, but I'm going to keep the extra ground wire.

[coW52Dodge]

Our truck beds are bolted to the frame through the wood of the bed. No metal to metal contact. You need to ground the lights to the frame with a ground wire or ground the steel bed to the frame. Later trucks used a steel floor and they were the ground.

My lights, mounted on the aftermarket bumper, were real dim so made up some beefy straps to go between the frame and the bumper, the battery and the frame, the frame and the tank and the frame and the front fenders for the front lights.

Even though there likely was some sort of connection through bolts and hardware, the ground connections were likely of fairly high resistance. The straps make sure of a good connection.

I also slobbered some fluid film on all these connections, to keep the corrosion at bay.

The lights burn my eyeballs out now and my gas gauge, previously pointing to empty, also came back to life.

[grey beard]

Hey Paul,

Sounds like you just passed Ele. 101 with flying colors. You are correct in your understanding of the ground path being equally as important as the insulated side of any circuit.

Pilothouse pickups have a "Z" bracket bolted between the frame and the rear lower bed skirt, behind the rear wheel on each side. These brackets will provide plenty of ground connection without running any other extraneous wires, IF you pull the brackets and spiff 'em up so they make good contact. A star lock washer under each bolt head would be a great idea, as well.

Personally, I like the two-tail-light look over the older four rear lamp look - just my preference, AND it has the added benefit of a more original look. I used LED bulbs - gotta' be red ones, not white, to show up behind these dark glass lenses - and they show up very nicely in bright sunligfht, even though I'm still six volts.

Good Luck

[pflaming]

Couldn't get the signals to work through one pair of lights, then discovered a descrepancy in the wiring diagram and my signal mechanism. Went to google and . . . there are several models of Signal Stat 900's, got to be very careful.

Found the Z straps. One is broken. I'm beginning to understand why it's hard to sell a vehical one fixed up and thus the price. Yet it is fun, if / when I get this truck running, may look for an old mopar car. My first car was a 50 Plymouth. I would like a 51 or 52 I like the lower hood on those models or 48-50 Chrysler.

Very few mopars even out here.

[bkahler]

I don't recall ever hearing about a Z bracket before. Any chance that someone might be able to post a picture of one?

Thanks!

Brad

[pflaming]

It's is not a true "Z". It is a piece of flat iron: one leg goes 90 degrees up the other leg on the opposite end goes down: ( '---, )

[bkahler]

It's is not a true "Z". It is a piece of flat iron: one leg goes 90 degrees up the other leg on the opposite end goes down: ( '---, )

Any chance of a picture?

Thanks!

Brad

[Dan Babb]

The timing of this post couldn't have been better.

I just installed the new tail-lights that I got from PowerWagon over the weekend and they don't light up.

I'm going to make up a ground that will go from the stud on the lights and then mount the other end to the frame and see if that helps.

If not, then I'll have to pull out the light switch and start tracing the power from there. I do have front lights now..just no light coming out the rear.

[pflaming]

Dan, I got tired of going back and forth to the light switch so I took a 20' wire, put clips on each end and used that as my hot wire to the back. I used that to get things going then I traced the wire back, saved me a lot of time. For my ground, I just drilled small holes in the bed frame and the truck frame and connected the two with a #10 wire, that grounded both rear lights.

Remember that there are two hot wires: (1) the tail light hot comes from the light switch; (2) the brake light hot wire comes from the hot end of the panel switch and goes through the brake light switch. Here I put a toggle switch in down by the brake master cylinder and used that to get the brake lights working. Will worry about the brake light switch later.

This is probably old to most but to two novices like me and you its 'rocket science'!!!

ps:Once I got the lights working with the bi-pass wire and switch I then only had to concentrate on the switch.

Now I am working on getting the truck engine running, so will now do a search on fuel pumps. The search part of this forum, used wisely is invaluable. I open a new work document, title it, then I cut and paste information from the forum to my document. Then I edit my document into a systematic step by step check list, print it out and tape that document to the truck. Saves a alot of time.

Edited November 16, 2009 by pflaming
PS