I'm having some odd electrical problems with my 1941 Chevy Master Deluxe and I thought someone here might be able to help.
I installed turn signals using an older American made turn signal unit that appears to be in good shape.
I changed out the flasher, which had a bad dent, for an LED flasher with a grounding wire as I was intent to switching to 6V LED. The odd thing is that the signals and brake lights work well with the key on but no engine running. Turn the engine on and the lights hyperflash, even with only conventional bulbs in place. What's more, after some time in the car the brake lights seem to weaken or fail completely, but then later they'll start working again. The turn signals will click as if they are hyperflashing, but the clicking will slow down and become more sporadic and minimal or no light from the signals. But the next morning with only the key on it will work fine again.
I have tried this both with LED bulbs and conventional and the problems are consistent regardless of bulb. I seem to recall trying a conventional flasher too and the problems persisted but I am going to try it again tomorrow just to confirm. I am pretty sure the flasher is not to blame as it claims to be able to run LED or conventional bulbs.
Another possible symptom: Out of caution I put a third tail light in the back window (6v) It seems to work fine at all times although it does seem to be a bit weaker when the other symptoms start. The dash lights I would swear weaken a bit too, but it is hard to say if they are just being drowned out by other car's lights.
The engine also seems to bog-out a bit (especially in second gear) when the gas pedal is pressed to about 1/3. Press it more or less and the problem goes away. This car has already had the fuel pump and carb cleaned/replaced so I think it might be a related electrical issue.
My first thought is that the generator might be failing, but that doesn't seem to explain why everything works fine until the engine is turned on.
Anyone have any thoughts on this? It's a bit of a puzzler.
It is pretty obvious that a new wire harness is called for with your electrical problems. I justify this on your previously posted pictures and the problems you described above. 4th Posted Picture . I am assuming most of the original 68 year old wire has been piecemeal replaced with and oddity of newer wiring but not all. The attached pictures were of a section of my 41 wiring, concealed by my headliner, before I replaced my entire wiring harness.
Hello, I changed out the flasher, which had a bad dent, for an LED flasher with a grounding wire as I was intent to switching to 6V LED. The odd thing is that the signals and brake lights work well with the key on but no engine running. Turn the engine on and the lights hyperflash, even with only conventional bulbs in place
Speaking to the above part only, I had this problem when installing a LED flasher with pigtail ground wire. The cause was electrical noise from the ignition system messing up the electronic timing circuits in the flasher. The solution in my case was to install another condenser from the POSITIVE side of the ignition coil to ground.This prevented noise from the ignition system from traveling back up the wiring harness.
Just wanted to follow-this up with what I hope is the end of the story.
I took it to an electrical specialist, and while he was NOT impressed with the rat's nest of wiring, the wiring did pass all his tests. Turns out there were two culprits. The LED flasher, despite promises on the package of being able to handle a mix of LED and conventional bulbs, appears not to be able to handle conventional bulbs if they are mixed in. I suspect Coachman's post above describes the source of the issue. But also, the rear right taillight bulb appears to have been damaged but still working. However, it was not grounding properly and was throwing off the rest of the system. The base of the bulb had a bunch of crud inside, so the bulb had separated from the base a little bit and was collecting water/rust/crud.
So, changing back to a standard flasher and putting in a fresh bulb appears to have worked. The engine bogging-out appears to be related to the fuel pick-up in the gas tank. So, first things first, I'll get that cleaned up and see if that fixes the problem. If not, electrical goes back to the top of the suspect list.
otrex, sounds like you have the issue with the lights sorted out. Good deal.
Just FWIW, I was thinking grounding issues when I first read your original post. It brings to mind another source of electrical gremlins, related to insufficient body grounding (which can affect lights, instruments, and so on). If your '41 is similar to my '53, the negative (ground strap) cable from the battery attaches to a bolt on the front of the head. If both end connections are clean, and the cable is in good shape, that assures a very good ground to the engine.
What that scheme doesn't assure is a good ground to the frame and body of the car. It relies on the various fasteners for ground continuity. I've even heard where the throttle linkage has become the primary electrical ground path to the body (with bad results), when motor mounts and so on are corroded. Not good. Anyway, the simple remedy is to attach additional ground straps from engine (which is well grounded) to the body and body to frame, at convenient places, assuring attachment points are cleaned to bare metal, then protected from corrosion.
The engine bogging at various throttle positions got me wondering if electrical, and perhaps the infamous throttle-linkage-as-ground issue. Your probably right, fuel pickup is a much more likely issue, but thought I would mention it.
Doug
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