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trrdster2000
11-02-2015, 09:09 PM
Getting the wiring put back on the Spit6 since is been raining and no good for painting the bonnet (hood).
The car was not a show stopper and the wiring had been butchered by PO, lots of black wires for any wire that was melted, unless there was a yellow wire closer. As example, they jumped the reverse light wire in the trunk with a yellow wire across the back. After taking the tape off the entire harness there was nothing to indicate a short. There was a little meltdown in the red three way for the plate light, but we had seen that and got new ones.
Now the ghost has appeared with a .13 OHM reading almost anywhere on the car if you attach a clip to the positive battery lead and touch almost anywhere you get the same reading. Oh, only with the key on. I just ran out of back tonight after 5 hours chasing this sucker. I will hook up the meter tomorrow and get the wife to watch it while I start unhooking different things. I thought I found it when I took the seatbelt and sensor plug apart, all it did was drop it a few OHM's, so there was a issue in that system.
Don't know if anyone can shed any light on this but will let you know what I find. I don't want to hook up a battery knowing I have a voltage leak somewhere. Not cold enough for a Spitfire or should I say barn fire yet.

I still have the front wires unhooked, but not touching anything, setting in a box all separated.

AHHHHH! Wayne

TR3driver
11-02-2015, 09:38 PM
What about if you pull out the top fuse? That would at least tell you whether to look at the white circuit or the green.

One trick that might help is to hook up the battery, through an old headlight bulb. The bulb will only pass about 5 amps, so nothing is going to burn up, but having some current flowing can make the problem easier to find. And besides, the bulb gives a good visual indication when the short is happening.

All wire has some resistance, so you can use your voltmeter to check if current is flowing in a given wire or not, by just checking the voltage from one end to the other. It won't be much, but you should see a few millivolts if there is 5 amps flowing in the wire. Another trick is to use a magnetic compass to look for the current.

trrdster2000
11-02-2015, 10:50 PM
Thanks Randall, they are all good directions and I will be on it first thing. Don't know why I didn't think of pulling a fuse first to get a idea on which circuit to check.
I was going to hook a battery up and thought I might get a smoke leak, LOL.
I found out he has had a problem with the battery going flat in a couple of days, so this has been there for a while.
Thanks again.
Wayne

trrdster2000
11-10-2015, 09:03 AM
Hi All, quick up date. Good thing we started looking. Found all kind of melted wires in the main harness, green wires were pretty much a solid lump for about 6 inches in the large harness after we took the wrapping off. Replaced one at a time from the GT6 harness and all looked good but had the ignition light on when the key was off. I checked the switch and found the White/red had been replaced outside the switch harness, so after spending a few hours just checking that part, nothing was not in working order, just cleaned up a few connections. The light turned out to be a wrong hook up on the alternator. The plug was long gone and just had the three wires and only two had good connectors. That brings up a little problem on the wiring. If you run the harness along the frame like it should be, because the six is longer, the wires are not long enough to reach either the alternator or temperature sending unit. Used a small roll of solder getting all this in good shape, just thankful the GT6 harness had some good sections.

Got the carb chokes and accelerator cables hooked up, you will need to use a GT6 duel choke cable and accelerator cable. We ran the choke one from near the passenger side tunnel area, which gave it a straight shot at the carbs and being a double, it just made things work easier. The cables are rubber covered but since they go near the positive side of the battery, we will put a plastic sleeve over them.

Getting closer.

Wayne

GTP1960
11-10-2015, 09:26 AM
Hey Wayne,

Can you post some pics of your spit project?

best regards,

Guy

TR3driver
11-10-2015, 09:41 AM
Found all kind of melted wires in the main harness, green wires were pretty much a solid lump for about 6 inches
Likely you know this, but JIC. The fuse ratings given in the Triumph documentation are in a weird obsolete British rating system. If you substitute modern fuses, you need to use fuses with a rating just slightly more than HALF of what the book says.


Here is a conversion chart, lifted from a long-ago Bussman fuse catalog:

Bussman Conversion Chart
English Type American Standard Replacement
50 amp AGC 30
35 amp AGC 25
30 amp AGC 20
25 amp AGC 15
20 amp AGC 10
10 amp AGC 7 1/2
5 amp AGC 3

trrdster2000
11-10-2015, 11:50 AM
Thanks Randall, I'm still using Lucas fuses from years of junk cars and buying parts boxes at yard sales. They may outlast me, but I will give the owner your chart and tell him to make sure to not give these wires a chance to smoke.
The pictures are all on the owners cell phone and he has yet to send them to me, I will try again.
I did want to tell all about a complete waste of time. The rear lights have always had trouble with the grounds and his was no exception. For those who do not know, the ground ring with the little feelers are aluminum and the little copper spring that sets on the outside of the bulb giving the connection are two different and troublesome materials. Over the years they oxidize and the connection is broken. You can heat the plastic with a heat gun, pull back the holding edge and clean the aluminum on a bit of sandpaper and also the copper, put some de electric grease on it, stick it back together and heat the edge and fold it over. This will give you a almost good connection. Now, use a solder gun and get a small drop between them, make sure the metal melts the solder or you will be just laying the solder on top of the metal, not good, and that is as good as it will get. You can add a small wire at the solder and make a ground to frame, I did that on the TR6 and I think someone was selling those a few years back. The waste of time now comes into play, BPNW has the single and double bulb holders for less than $5 each. It's been raining for two weeks here, so I wasted a bunch of time. Might be a good winter project when you are snowed in.

Don't laugh, Wayne

Andrew Mace
11-10-2015, 01:20 PM
...Now, use a soldier gun and get a small drop between them, make sure the metal melts the soldier or you will be just laying the soldier on top of the metal, not good, and that is as good as it will get. You can add a small wire at the soldier and make a ground to frame, I did that on the TR6 and I think someone was selling those a few years back. The waste of time now comes into play, BPNW has the single and double bulb holders for less than $5 each. It's been raining for two weeks here, so I wasted a bunch of time. Might be a good winter project when you are snowed in.

Don't laugh, WayneI'm trying NOT to laugh, Wayne, but I have this mental image of you raiding your toy box for little metal military figurines (soldiers) to melt down in order to make a good ("solder") connection. :wink:

trrdster2000
11-10-2015, 04:17 PM
Andy, why did I do that? I guess old age does it, I spelled it wrong the first time and just kept going. No wonder it takes me forever to get things done.

Keep watching, I may stumble into doing it right.

Wayne