attack of electrical gremlins

[old ugly]

i had a weird gremlin attack my car today.
i was on a club cruise, turned on the rt hand signal lights, made the turn, shut off the signal light, the car started running ruff and died.
i changed the fuse, started the car and limped it to the destination.
we worked on it and finally got it to run half decent.
the signals no longer worked so i thought the issue must be in the signal stat, i unhooked the power wire to it. i drove home.

tonight i fond every light bulb in the signal system was burnt out. that also means i had no brake lights, not good.

my journey now is to find out why all the bulbs would burn out at the same time. 6v system with 6v bulbs and not all of them were off shore made.

wish me luck

if you have something like this happen let me know what you did to fix it.

thanks
ou

[40-A Twins]

Same thing happened on my coupe years ago when I was arriving home and turning right into our driveway. Right side cowl light and both rear lights burned out, fuse blown and car would not start again. With this incident in mind, I installed the signals on my 29 roadster to work independent of stock lighting wiring and to use LED lights to reduce the load on the wiring. Still working on the roadster signal installation. After the coupe fuse and burned out bulbs were replaced the gremlin never returned. My best guess at the root cause is the fuse burned out, and the generator output was more than the bulbs could handle once the battery was taken out of the circuit.
Kevin

[nkaminar]

I'll go with the Twins. The generator can produce very high voltage when not hooked to the battery. Just make sure all electrical connections are secure and look for possible shorts. A separate fuse for the turn indicators, lights, horn, etc. that is not part of the charging system will eliminate the generator becoming disconnected from the battery. It requires some modification of the electrical system. I have a distribution block with fuses mounted to the engine side of the firewall with magnets. Doesn't look stock but works well. I had a short in the wiring for the fog lamps. It blew the fuse but everything else continued to work.

[katy]

Originally Posted by old ugly

if you have something like this happen let me know what you did to fix it. thanks ou

Check your battery grounds, both at the battery and the other end, chassis and/or frame. An extra cable between the frame and engine/trans is a good idea.

[old ugly]

i agree with the voltage output theory.
all 4 lights were burnt out and the signal flasher was burnt out.
i replaced all the lights and the flasher and i cut the charging rate down on the generator.
works good in the shop at high idle, charging about 7amp without any lights on.
we shall see what happens.

Katy, i will do that if it does it again, good idea. power may have tried for ground through the light bulbs.

ou

[Ruth]

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Originally Posted by old ugly

i agree with the voltage output theory.
all 4 lights were burnt out and the signal flasher was burnt out.
i replaced all the lights and the flasher and i cut the charging rate down on the generator.
works good in the shop at high idle, charging about 7amp without any lights on.
we shall see what happens.

Katy, i will do that if it does it again, good idea. power may have tried for ground through the light bulbs.

ou

Probably a good idea to do as Katy suggest even if it doesn't do it again
.

[Patrick L.]

7 amps seems pretty high to me unless you do a lot of night driving.

I think a 2nd heavy ground wire is a good thing.

[Badpuppy]

You apparently lost ground connection between generator and battery. Generator voltage went way high and burned everything out. Add a dedicated ground path between gen and batt using a #12 wire between cutout mount (#10) and grounded battery post (1/4"). The incidental mechanical fasteners between engine and frame are good conductors when they are new. They're probably not new anymore.

[Will N]

Do you have an original cut-out on the generator, or one of the voltage regulators that are available? I had one of the voltage regulators where you have to turn up the output of the generator by moving the third brush. Something fried in the regulator while I was running at high speed and I ended up frying my generator, along with other electric components.

[Badpuppy]

Originally Posted by Will N

Do you have an original cut-out on the generator, or one of the voltage regulators that are available? I had one of the voltage regulators where you have to turn up the output of the generator by moving the third brush. Something fried in the regulator while I was running at high speed and I ended up frying my generator, along with other electric components.

The Fun Projects regulator was not a good design. Quick and easy, but subject to what you describe. Thankfully it is no longer available.

[bobbader]

This is a long shot ................ You mentioned the fuse blew and I'm assuming it was the fuse mounted off the starter switch since the car started to run poorly. Do you also have an inline fuse on your signal light power wire? If the fuse in your signal light power wire is of higher amperage than the amperage on the starter switch mounted fuse, and even if the short that caused the problem is in the signal light system, the starter switch fuse might blow before the inline fuse in the signal light power wire. This will cause the power surge talked about in other posts and blow out the bulbs quickly. Try a lower amp inline fuse to the signal light switch. If that fuse blows, it will hopefully isolate the problem to somewhere in the signal light wiring.

Just a guess. Good luck. Bob Bader

[old ugly]

here is the diagnosis and solution so far, i found that i had two issues.
--the first chain of events was.-- the ignition switch wire shorted against the ignition switch housing. that blew the main fuse at the starter. i was making the turn with the signals on when that happened.
--then it was running on the generator which was putting out way to much power and fed that through the signal light system. or it was trying to find ground through the signal light system. unsure. but every thing in the signal system blew.

here is the fix
-i traced the short to the ignition switch and fixed that.
-i added the ground strap from the frame to the engine,
-cut down the charging rate on the generator.
-i moved the power supply wire for the signal system to the battery, it is not on the main fuse
-then changed all the bulbs and flasher in the signal system.

so far it seems to work ok.

just working my way through the hoky stuff on this car.

[Patrick L.]

Its always good to hear about the fix.

[Y-Blockhead]

Originally Posted by old ugly

here is the diagnosis and solution so far, i found that i had two issues.
--the first chain of events was.-- the ignition switch wire shorted against the ignition switch housing. that blew the main fuse at the starter. i was making the turn with the signals on when that happened.
--then it was running on the generator which was putting out way to much power and fed that through the signal light system. or it was trying to find ground through the signal light system. unsure. but every thing in the signal system blew.

here is the fix
-i traced the short to the ignition switch and fixed that.
-i added the ground strap from the frame to the engine,
-cut down the charging rate on the generator.
-i moved the power supply wire for the signal system to the battery, it is not on the main fuse
-then changed all the bulbs and flasher in the signal system.

so far it seems to work ok.

just working my way through the hoky stuff on this car.

Good job OU.

When people install a main fuse in the system, I sometimes wonder if it would not be better to wire the generator/alternator to the battery side of the fuse instead of the fused side. This way if the fuse blows the generator/alternator doesn't 'over amp' the system. But then, of course, if you blew a fuse the engine would stop running also. And the ammeter would not read the charge. Just thinking out loud...

Most of my separate 'systems' have their own fuse so I really don't need a main fuse in my Town Sedan. Some of the smaller 'systems' share a fuse (i.e. dome light, dash light, 12v charge port, etc.)

[nkaminar]

Blockhead,

That is a nice insulation. I put mine on the engine side for better access. I don't crawl around as well as I used to. It is attached with a magnet. The hole in the firewall was already there.

[bobbader]

Sounds like you got it nailed. Nice job of isolating the problem, fixing it, and making other logical modifications to avoid problems down the road. Well done.

Bob