Electric Troubleshooting

[lloyds-son]

Hi Triumph Talk people, I am new member having just joined a few minutes ago. I am working on bringing back to life a 1968 TR6C. Here is my problem: no electric power except the horn is working. I have installed a new wiring harness on the bike, charged my good battery, double, tripled checked all connections especially the ground. As part of my trouble shooting, I checked the ignition switch by removing it and then connecting it on my 1970 TR6R and the ignition switch works fine on this bike. I have used my multimeter to check coils and battery ground circuit. I have the two bikes side by side to double connections, disconnect & reconnect to make sure I have everything right. The headlight will not light, no spark at the points. I have followed the Triumph workshop manual - section H to check low tension circuit. and I don't get a reading at the coils, the manual reads: "no reading on the feed side indicates that either the ammeter is faulty or there us a bad connection along the brown/blue lead from the battery" The new harness has leads for ammeter, but the TR6C doesn't have an ammeter so I have wrapped the leads with electrical tape and left them unterminated. Could this be open circuit problem? Is there another area I should be looking? The harness I bought is a cloth loom, OEM Lucas product and it seems unlikely that the harness would be defective. I sure would appreciate advice from any folks have been down this road before. Thank you!

 

[grandpaul]

Yes, that ammeter circuit must be complete!

 

[lloyds-son]

Aahah! Thank you. Is there an alternate way to complete the circuit without the ammeter? As I'm sure you know, the TR6C does not have the ammeter.

 

[grandpaul]

Just slip a section of heat-shrink tubing over one of the wires, bolt the 2 connections together with a small screw and nut, grind off the excess length of screw threads with a dremel, slip the heat-shrink tubing over the screw/nut, and shrink it in place.

Voila' (that's French for "she's done")

 

[lloyds-son]

It works!! I'm so happy

 

[Rudie]

It works!! I'm so happy

Excellent.

TR6C
The new harness has leads for ammeter,
The harness I bought is a cloth loom, OEM Lucas product

You weren't sold the correct harness; '68 US-market 650 parts book - http://www.tioc.org/partsbookstriumph/pb-tri-650-1968 -no6 99-0880.pdf - shows different Lucas part numbers for the TR6C harness - 54953440 - and the TR6R/T120R one - 54953443; as you say, TR6C doesn't have an ammeter, other two do ...

Or Wassell of ill-repute strikes again. Given the "Lucas" that made your bike's original electrics was taken over in 1979, forgive my scepticism that you were sold an "OEM Lucas" harness. The company that took over - TRW - never displayed much interest in the old vehicle parts (TRW had taken over Lucas primarily for the aerospace division) 'til 2014(?) when Wassell (presumably in exchange for a large amount of readies) were granted an exclusive licence to use the "Lucas" branding and packaging on its often poor quality products. If your loom had a part number prefixed "WW" in addition to one of the aforementioned original Lucas part numbers, it's Wassell ...

I have followed the Triumph workshop manual - section H to check low tension circuit.

If you're going to 'do' electrics, you'd be wise to grasp some first principles:-

. The basics of the "Triumph workshop manual" were written over fifty years ago, and updated - sometimes haphazardly - for about another ten years; i.e. it hasn't been updated in nearly another half-century.

. The manual was written for time-served mechanics who worked forty-odd hours a week on, if not solely Triumphs, then similar engineering. What it wasn't written for was amateurs - and I don't mean that unkindly.

. As such, the manual's authors expected the reader to know that, rather than starting with the "low tension circuit", you start by checking the battery on a battery-equipped bike - not a lot of point checking the low tension circuit, the ground, the ignition switch, yadda, yadda if there's bugger-all coming out of the battery or the fuse has blown ... or you've left the ammeter leads unterminated ...

. If you can't read a wiring diagram, best learn quick - even if you know someone who knows the mechanics of these old junkers, most mechanics I've met know as much about even basic electrics as I do about astrophysics. Basic principles are, if it leaves battery -ve, it has to make it back to battery +ve for anything in between to work; there must be at least one thing in between that's either an ignition coil, light bulb or horn ... or it's a short-circuit and that's why the fuse keeps blowing; if you get lost, return to the battery and do not collect $200.

Voila' (that's French for "she's done")

You speak French like a native ... of Texas ... Literally, "Voilà" means, "Look there" ("Voir là"); idiomatically, it's simply an interjection - "There it is!", "Behold!", "Lo!", "Ta-daa!", etc.

Otoh, "She's done" would be (if you mean literally), "elle a fini".

 

[grandpaul]

You speak French like a native ... of Texas ...

Somebody is 1) too serious, and B) doesn't know that I don't use emoticons.

 

[Rudie]

Somebody is 1) too serious,

Not here, gentle leg-pull only.