Spitfire Spitfire lights

I installed a new wiring harness in my wife's MKII Spitfire after letting a lot of smoke out - burned / heated / melted the red circuit from the left rear lamp to the front of the car, under the dash. The folks I bought the harness from suggested adding a fuse in the red circuit. Since electricity is really a magical art, are there any suggestions in placing the inline fuse?

Since the harness is new, my neighbor, a car guy also, suggested relays for the headlights. I found a diagram, but I don't know exactly where to install the apparently two relays, high and low beam, where to cut the wires, and where to open the vinyl tape to get at the headlight wire.

Other problems: the overdrive is not operating at this time, and the gas gauge has issues - registering a full tank.

Trevor Triumph

Hello Trevor
On the TR3A there is an inline fuse that was added by Triumph that goes between the light switch and the tail lights. It is right under the dashboard.

Relays in the headlight circuit can help as they reduce the load on the light switch. There may be some wiring information on the web on adding relays to the headlights on a Spitfire.

What kind of overdrive does the Spitfire use. There may be an interlock so the overdrive only works on certain gears.

The fuel gauge may be a bad ground to the sender or a bad sender/gauge.

David

Thanks. I'll add the in line fuse near the switch on the "lights" side. I'm thinking the relays for the headlights may take some effort - I may have to undo the tape wrapping. Perhaps it is a ground, since the gauge worked properly before the harness replacement. I wonder if I have the wire from the voltage stabilizer on the wrong terminal.

T.T.

When adding anything to elect. circuits have a print made that show's additions, using a fuse block say the new blade fuses ( some fuses glow when blown ) NOTE UK AMP values are not the same as US. If headlights are upgraded a relay is needed. Instead of opening harness find a opening the new fuse block with added space is or may be best access and looking.. As for the gas gauge it reads to ground so clean and the float may be bad not the sending unit. When replacing wiring clean all ground connections. Madflyer

There should be a fuse for the "running light" circuit (red wires) already. Headlamps were not fused; flasher and brake lights were on the other fuse circuit. See #14 on http://www.fairpoint.net/~herald948/database/wiring.htm#3

So perhaps I'll save myself some labor if I let the red circuit alone. Good news.
I'm thinking I have wires in and out of the voltage stabilizer and perhaps the at the gas tank somehow mixed up. The gauge was working before I changed the wiring. In the next day or two I will redo the instrument panel, I can't find the proper wire for the wiper motor (bad lighting) and there is a leak at the oil pressure gauge. There seems to be a "jumble" of wires behind the instruments and the copper tube for the gauge adds to the mess.
T.T.

The story that never ends... The wiper and blower motors work after replacing the fuse. The fuse looked alright, and when attached a light it worked eventually. The fuel gauge appears to be working. Now to tackle the overdrive and oil leak. Thanks for all the suggestions.
T.T.

I spent the day, Saturday, working on electrical gremlins: fussed with the another car's overdrive solenoid - maybe it is OK. I'll put it in and find out. The important thing is my wife's Spitfire: ALL lights work, overdrive, blower motor and wipers work.

The horn even worked for a while. On the way home I heard the sound of something breaking and sure enough the horn wouldn't respond to the steering wheel horn button. The sort of ball end to the horn brush broke. I replaced the slip ring using an incorrect part or the horn brush is the wrong one. I installed an aftermarket steering wheel; I don't remember the brand.

Any ideas?