Smoke escaped from wires today

RedApe53 · Mar 17, 2014

I lost some of the smoke contained in my wiring tonight !? 69 Fastback. After installing my dtaylor head steady i got no spark. I have a Boyer ignition that was previously grounded to the original head steady. i affixed the ground to the same head steady-plate stud (this is rubber iso'd). so, in checking for spark, i had the plugs out cranking away on the kickstarter.....nothing. i moved the wire apparently and got some brute sparking that apparently traveled through both my arms enroute to the plug tip! so, figuring it was a bad ground i attached the ground wire to the coil backing plate near the frame headstock. screwed plugs in, started right up, actually ran good. shut it off, went & got helmet and jacket to go for a quick ride. wouldn't start, wouldn't pop, no spark. i noticed the ammeter was pegged to the (-) negative side;;;; thinking wtf? then the scent of escaping smoke. it was coming from the battery/neg side fuse holder. the fuse doesn't appear blown (?) and when i took it out another small piece of silver metal came out of the holder. perhaps the contact end in the holder? i have disconnected the battery for the time being.....

i did have the battery on the charger for about a week @ a 2A rate. i have looked at the wiring diagram in the book and will get my meter and start checking for a fault. i hope one or more of you have experienced similar and can point me toward the problem/fix. thanks, guys.

ILLF8ED · Mar 17, 2014

Check connections to the Zener. Happened to me a couple of decades ago. The Zener ground wire insulation was toast.

Hobot · Mar 17, 2014

Its common for me to get electrical faults after some other task completed fine. Sometimes its just the freaking fuse and highly recommend new age blade type. Otherwise best wishes with extinguisher handy. If boyah fires while messing with wires then track that fault down till it don't.

1up3down · Mar 17, 2014

i did have the battery on the charger for about a week @ a 2A rate.

Hi Chris,

I remember being in your garage and you showed me your battery charger

if I remember correctly it was a "straight" or constant 2 amp charge, but I don't recall it having the automatic stop charging when fully charged feature as a true trickle charger would, am I wrong on this?

very possible you over charged your battery being hooked up for two weeks and with the negative terminal being the live lead it seems to have cooked your fuse holder, hence the piece of metal inside there in spite of the fuse not being blown

I would go get a new fuse connection at auto zone or radio shack and put in place of the one you have

the battery being over charged could also explain the strong charge jolt you felt and smoke issues

the battery is supposed to dump excess charge into the Z plate but maybe it couldn't handle that

remember when I suggested you run two more thick ground wires down to your oil filter securing bolts?
one from the positive battery terminal and one from the left side back of engine to frame bolt to filter

any questions, you have my phone number

John

motoracer8 · Mar 17, 2014

I have a jar of Lucas smoke if you need it. I picked up a couple of jars at a swap meet a few years ago.

I haven't had any leaks lately but a jar of smoke is nice to have around.

Rohan · Mar 17, 2014

Never forget that these bikes are +ve POSTIVE EARTH.
Getting it wrong anywhere is certain to try to cook the Zener diode, and smoke the wire(s) that go to it.
Good Luck...

RedApe53 · Mar 17, 2014

John, i do/don't remember that exactly but there was a ground strap i installed from the neg terminal to a frame bolt, last year. it was another one that lost it's smoke. i have removed it. auto zone say battery is NG so will pick up new tomorrow. you may be right though, it is a 2amp charger.....i just went and looked at the charger. you're right, no auto shut off. F! is it your opinion that a battery will cure my problems and negate stupidity, both? i also washed my cellphone some time ago, i need your number again. if you're inclined.... the bike did sound good for the 3 mins it ran. i dropped the needles to lean it out more. plug was still showing too black. I'm also gonna check the zener grounding. i re-grounded the boyer too. i plan to check boyer fault=finding possibilities before i put the battery in. good to hear from you.......

only wires that fried were on neg side, ground & fused wire. I'm thinking the diode should be ok but will test. thanks

#

Rohan · Mar 17, 2014

RedApe53 said:
auto zone say battery is NG so will pick up new tomorrow.

Who are autozone that they say this. ?

ALL Commandos were built +ve earth, so unless they know for sure its been converted over,
this will likely do some serious electrical smoking !!

olChris · Mar 18, 2014

RedApe53 said:
I lost some of the smoke contained in my wiring tonight !? 69 Fastback. After installing my dtaylor head steady i got no spark. I have a Boyer ignition that was previously grounded to the original head steady. i affixed the ground to the same head steady-plate stud (this is rubber iso'd). so, in checking for spark, i had the plugs out cranking away on the kickstarter.....nothing. i moved the wire apparently and got some brute sparking that apparently traveled through both my arms enroute to the plug tip! so, figuring it was a bad ground i attached the ground wire to the coil backing plate near the frame headstock. screwed plugs in, started right up, actually ran good. shut it off, went & got helmet and jacket to go for a quick ride. wouldn't start, wouldn't pop, no spark. i noticed the ammeter was pegged to the (-) negative side;;;; thinking wtf? then the scent of escaping smoke. it was coming from the battery/neg side fuse holder. the fuse doesn't appear blown (?) and when i took it out another small piece of silver metal came out of the holder. perhaps the contact end in the holder? i have disconnected the battery for the time being.....

i did have the battery on the charger for about a week @ a 2A rate. i have looked at the wiring diagram in the book and will get my meter and start checking for a fault. i hope one or more of you have experienced similar and can point me toward the problem/fix. thanks, guys.

If you have "only" installed a DT head steady which is clamped to frame........... Is your frame powdercoated? painted at the clamp point?....... If there is not a gauranteed grounding point for the elects there will be problems... Get the 80grit out and scuff up some of the grounding points

1up3down · Mar 18, 2014

there was a ground strap i installed from the neg terminal to a frame bolt, last year

Chris, you have a positive ground electrical system

thus it is your positive battery terminal that gets grounded to frame

and not the negative terminal as you said you put a ground strap on to frame

I will text you mid morning

Hobot · Mar 18, 2014

Bad no conducting connections don't cause smoke and if fuse didn't pop on first mis-connecting ground then the fuse is too hi amp rated to protect wires and lucked out battery was bad or might be re-wiring the melted or burnt up sections and mess. If I had iup/3dn to help me I would of learned the above the easy way.

PeterJoe · Mar 18, 2014

From what you described, you got yourself a dead short. Seeing that your ammeter is pegged on the negative side, it indicates you hooked your battery up correctly otherwise it would peg on the positive side. Of course that assumes that your ammeter was hooked up correctly. Your fuse should have blown. The only reason I can figure that it did not blow is because your fuse rating is incorrect. For American fuses, you don't want more than 20 amps or possibly the piece of metal that fell out of your fuse holder was bridging the fuse itself so that the fuse could never blow.

A poor ground will not cause excessive current through your system, so that is not your problem. Zener diodes can go bad which can blow a fuse. Seeing how your fuse was not properly protecting your circuit, that could have caused the smoke in your wires. Maybe when installing your gas tank a wire got pinched causing a short circuit or possibly a connector worked loose exposing bare metal to ground.

Of course if you left the battery hooked up with the dead short long enough, you could simply follow the burned wire to the point where is is no longer burned to locate the short. However that is definitely not the way to go!

Hobot · Mar 18, 2014

Bad ballast resister can smoke its power wire but that item should not be in circuit with a boyah installed. The many extra police dead end loops and switch backs add to the tracking hassles.

chaztuna · May 28, 2017

motoracer8 said:
I have a jar of Lucas smoke if you need it. I picked up a couple of jars at a swap meet a few years ago.

I haven't had any leaks lately but a jar of smoke is nice to have around.

Hey, you can buy it on eBay! Someone had a great time making this gag auction.

Smoke escaped from wires today

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