Federal 175 with contact problems

Kevin Lynch

PCS Member
I bought a 175 about a year ago and just got it out of the wrapping (excellent packing job!)
All four bulbs work fine when tested. When in their places, and the light is powered, one red light doesn't come on, and the other red one only comes on for a second when it is in the same spot.
I've seen these apart before and figure something is warped and avoiding contact. Where to begin?
Thanks and Happy New Year!
Kev
 
Take the bulbs our and see if the wire contacts are good. There is a disk at the bottom that has a button that contacts the disk, and that is how power is sent to the bulbs. Possibly there is some corrosion on the disk that is interfering with the transfer of current.
 
The original wiring was a lacquer coated cloth wire. If you are going to be replacing the original wiring, you should both solder and crimp the connections, and then use heat shrink tubing to permanently seal the connections. If you need any help, just let me know.
 
Paul- thanks. I love the heat shrink- its great insurance. I was trying to figure out what coated the original wire. Looked like glue over paper but now that I know about the lacquer coating, I get it. Ok and now here are the results and photos of my investigation of why the clear bulbs work and the red's don't on the "suspect" 175:
1. Red lights only light for a split second at the same point in the rotation.
2. Clear lights always work.
3. If you're like me and you want to indict the usual suspect: GROUND, it's not the ground, because one clear and red are grounded together! See photo.
4. Power to the clear bulbs is from a wire coming through a brass and rubber collar and up to one of the clear bulbs; then there is a jumper wire to the other clear.
5. Power to the red bulbs comes up the center shaft. See photo.
6. What I haven't exposed yet: the stationary plate and the rotating- about 1/8 inch apart- I need to get the rotator off and expect to see 3 contacts: clear, red, and ground. That's what I'm up to.
ANYONE have any other ways to get between these two parts - ?? maybe the spring under the contact needs to be pulled a bit??????
The red, green, and black marks were put on just to keep a visual on ground wires and hot. I'm replacing all 4 ground wires to the bulbs- thus the black wire seen.
THANKS EVERYONE!

47957534-BD5C-4EE1-938C-9BBACB4CA57D.jpegEBD3C89C-DC3A-495C-82E4-043E0878054F.jpeg
 
The light can be wired so that you can turn off the the white bulbs that is why they are on one slip ring and the read the other. So you have power to the brush for the reds? And the slip ring is clean? The shaft is not bent as it goes up? The brush is not losing contact with the slip ring as it goes around? All things to check on.
 
Ed thanks for the usual help. The photo here shows an arrest being made- and the perp-walk....exposed!!!!!
The killer is that I could have identified this w/o spending a week taking the entire thing apart! Going to clean up this
metal- figuring a good contact is prevented by rust and age.
CDDFAFD2-4DA4-4C11-A911-5A3382C3EC25.jpeg
 
The last 175 that I worked on was about 10 years ago, and I have forgotten a lot about them since. I am certain that you will be able to figure this out. I would use a minimum of 14 gauge wires, but 12 gauge would be best. Problem is that 12 gauge is difficult to work with, unless you can find some 12 gauge machine wire, which is manufactured with a better quality copper, is more flexible, and has more strands than automotive wire. This is what was recommended to me by Kevin O'Connell many years ago.
 
1/2/21: Update: when I apply the power probe III to the rotating device under the unit, the PP shorts out. When I apply power to the top of the shaft, the PP shorts out (has an internal circuit breaker for those of you not familiar with this must-have tool). When I check continuity from the bottom to the top, it's there, but that isn't affected by a short. So the intermediate tube (non-conductive) has to have failed. This reminds me of taking a unity spotlight apart- the shaft you can see (which I'm guessing is ground), the shaft with the electricity, and the intermediate shaft to keep the other two apart. I'm going to have take the top level of brackets off to see the top of this "suspect" shaft. Stay tuned.
 
Think about this......if I recall correctly, with a 3 position switch wired properly you could stop rotation of the light (reds not lighted then) and use the downward facing clear bulb as a "ditch light". Years ago. I had a combination car that had that "feature". Cannot remember how it was wired. That MIGHT be contributing to your problem.
 
The normal problems are bad conections dirty contacts and warn insulating. Now me i like to use the battery charger and work it with a full 12 volts one step at a time till you find the trouble spot. Then fix that first. Then if the the light need gone threw completly do that. Nothing worse then redoing everthing only to find the origional problem is still there.
 
Russell Street - it can be done that way, because that disc under the main plate only carries power to the horizontal bulbs, and the wire with vertical contact goes to the angled bulbs....someone connected the two along with the motor wire to the incoming power. The good thing is that I've proven the clear bulbs are getting power and the red bulbs are not. As I mentioned this morning, the problem is inside the shaft that brings the power up to the red bulbs. You sure learn a lot in this hobby!
 
Ok I think our mission is close to an end. The insulating tube looks fine. the shaft that brings the power to the red lights is what's in the picture, with the insulating tube. I suspect now that the washer at the bottom of the insulating tube is worn (its not metal) and thus the round piece at the bottom is touching the mechanism itself, which is grounded. To be continued.461828C4-F689-4C3E-A689-0239BDFBAF0A.jpeg
 
Cut a new isolator out of a piece of plastic and see if that does the trick. The more you get into these lights the more you see how federal used the same pieces on different lights to do different things. That shaft is the same as all of them.
 
Back
Top