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Rewiring a 1967 3000

ralphledger

Freshman Member
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Looking into replacing the harnesses in a 1967 3000 MKIII. I would appreciate recommendations for suppliers. Looking for concours quality components. I have recently contacted Moss Motors and from their description seem to have high quality components although I have not physically seen their products. Their under dash bulb sockets are the new bayonet push in versus the original half a turn screw in type.

For you concours guys would non-correct bulb sockets make a difference in judging the car? I would opt for safety and convenience and the bayonet type would work for me but would appreciate input.

Are there any other harness suppliers that you forum guys would recommend?

Very Respectfully,

Ralph
 
Another source is British Wiring (britishwiring.com)

NFI, etc. All the looms I've seen are good quality (although I did get a BN2 loom with a mis-identified wire from Moss).
 
I believe they were originally made by Autosparks in Nottingham UK. They're still in business and a really nice company to deal with. They stock everything else you need like special grommets and clips and if you have spotlights or anything additional you'd like to incorporate in the loom, they'll do it for modest extra cost. I think he cost is a little over $200 minus UK VAT but extra for shipping.
 
Though I would keep the original dash harness if possible, its not something that is judged during Concours. Crawling up under the dash and pulling on the wiring isn't part of the inspection. Function will earn the most points . British wiring has a great product and it will only differ in a few small but visible details from Moss offering.
 
Though I would keep the original dash harness if possible ...

I've rewired a BN2 and a BJ8, in both cases the 'dash harness' was an integral part of the loom. To keep existing under dash wiring you would have to cut and splice (or reconnect), oh, a dozen or so wires give-or-take.
 
I've re wired a few also , but was thinking the instrument bulbs were on a separate loop . I'd still recommend British Wiring.
 
The instrument light sockets are different than the originals so you have different bulbs. You can cut off the bulb sockets from the old harness and use them. If you do use a bare metal splice with heat-shrink over it.
 
EV2239: $200 seems very low. A quick adding up of the Moss harnesses, grommets, clips and etc. yields almost $750 more or less. I should recheck that number because I'm operating from memory but I think I'm ball park. I will attempt to contact Autosparks.

I appreciate everyone's immediate responses. Excellent information and I appreciate it.
Cutting and splicing the old sockets onto a new harness makes no sense to me. I won't reuse components with fifty years worth of corrosion and wear on them. The bayonet bulbs are so much easier to replace when burned out. Any ballpark estimation of the time it took for the R and R from those who have done the job before?

Ralph
 
I also have used AUTOSPARKS for one other car MG TD- I agree for quality and originality of the hearness at good price (NOT personal interest in AUTOSPARKS bus.)
Most part of good results depend to the preparation works I have indentified and labelled all wiring(I have also exagerated with complete testing the hearness out of the car)
https://get.google.com/albumarchive.../AF1QipNKomxPCTokMeYfO_GJKPc_i3m-FiWHi-Z4tMOA
see other photos of the album and find others wiring diagrams (100/6)and dash connections designs that can help you

My suggestion is NOT use Battery during the harness work and firsts test
use a little 12V source max 10A with automatic fuse(if possible)
this avoids the burning and the facility of the connection works (the orange supl- in the photos)
NOTE also the large poster of the wiring diagram that can help a lot
 
... Any ballpark estimation of the time it took for the R and R from those who have done the job before? Ralph

I did it in a weekend (12-15 hours or so). Cut the old loom out in segments, and replace one connector at a time. The only clip I couldn't reach to remove is on the driver's side of the transmission tunnel; I cut the old wire out and tie-wrapped the new to the clip until the next time I had the engine out. The most inconvenient/painful segment is where the main loom connects to the front light loom, under the shroud at the front ('under' the badge).

Get one of these: https://www.britishwiring.com/Tool-Snap-Connector-Tool-p/ssc1.htm, or create equivalent by cutting slots in a pair of cheap pliers. I recommend putting dielectric grease in the connectors; helps prevent corrosion and the pervasive Lucas gremlins. Have a wiring diagram/schematic handy (I think someone on this forum has a .pdf or .jpeg available); I have encountered mistakes in a loom.
 
FWIW

When I rewired my BJ7, the harness came from Ahead4healeys, I sat down and spent a wet afternoon with the good book (workshop manual electrical layout) and the harness along with an electrical meter and in my case some sticky labels -I now don't recommend sticky labels - they come off too easily, should have used white electrical tape and a pen. I checked all the wiring out - what went where and labelled it so. At this point I should advise you that if you have an overdrive - that harness is separate and must also be ordered ( don't ask how I know - lol) I originally cut the harness as it passed through the bulkhead on the engine side and removed it from the engine bay, then I removed the dash board and cut the wires from the instrumentation/ fittings as I removed them, leaving a short tail connected to them so I could see what wires went where when it came to connecting the new harness in. I also removed the heater box as I was installing new rubber water connections - then removed the rest of the harness on the cockpit side of the bulkhead. I was surprised how easy it was to install the new harness when dealt with in this way. I was quoted ÂŁ600 to do the job by an electrician and it would take two men two days - rubbish. I then tested the installation and a fuse kept blowing on the ignition circuit, by removing all the wires on one side of the fuse and installing them one by one and switching on, I discovered that the fault lay in the wiper motor - of course it was the last wire to be connected. On stripping the wiper motor I discovered that the carbon brushes were gone and the brush holders had worn the commutator down. I acquired a new motor for a BJ8, second hand and cleaned it up, checked and installed it and all was right in the world.


:cheers:

Bob
 
I did it in a weekend (12-15 hours or so). Cut the old loom out in segments, and replace one connector at a time. The only clip I couldn't reach to remove is on the driver's side of the transmission tunnel; I cut the old wire out and tie-wrapped the new to the clip until the next time I had the engine out. The most inconvenient/painful segment is where the main loom connects to the front light loom, under the shroud at the front ('under' the badge).

Get one of these: https://www.britishwiring.com/Tool-Snap-Connector-Tool-p/ssc1.htm, or create equivalent by cutting slots in a pair of cheap pliers. I recommend putting dielectric grease in the connectors; helps prevent corrosion and the pervasive Lucas gremlins. Have a wiring diagram/schematic handy (I think someone on this forum has a .pdf or .jpeg available); I have encountered mistakes in a loom.

Bob and Andrea:
Really great suggestions. I especially like the suggestion of 12V low amperage pre-testing of the harness install prior to connecting to the lead acid battery. Bob, I am surprised at the short time it took for you to make the change out.

Thank you,

Ralph
 
Hi All,

If you are not looking to have a concourse installation, I would suggest considering the installation of additional fuses on critical components as part of your project. When considering a harness vendor, see if they have, or will, add an under-dash fuse box to complement (not replace) the original firewall fuse box. Many of us have added fuses and relays to an installed electrical system to add protection to unprotected critical electrical components (ie. head and driving lights, OD components, added sound systems, etc.). However, adding in-line/fuse-box and relays at this time seems ideal and, if you are going to consider doing this at all, I would suggest you incorporate/integrate this activity into your harness replacement.

Just a thought,
Ray(64BJ8P1)
 
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I installed a Mosss harness on my BT7. Everything fit correctly except they only provided two light bulb sockets for the gauge lights and they were not the screw in type as original. I just cut off the original sockets and short section of wire and soldered them Into the harness. Also the wire gauge on the new harness may be the same as original but the diameter of the pvc insulation is smaller, at least to my eyes. I turned on the headlights yesterday for the first time in 30 months and nothing melted. I think the lights are brighter now that I installed relays. Not quite ready for a night drive...
 
I installed a Mosss harness on my BT7. Also the wire gauge on the new harness may be the same as original but the diameter of the pvc insulation is smaller, at least to my eyes. ...

As an Electrician i have found that sometimes older insulation on conductors will absorb oil and expand or expand as the insulation deteriorates.
Also newer conductors have a better insulation rating for higher temperatures and can be made thinner.
 
58 Special, I agree that the new insulation is probably better than the plastic produced 60 years ago so I'm not worried about the performance of the new harness. I made the comment because if your having you car judged, someone may notice the wires "appear thinner" than the original. I don't know if judges take things to that extremed.
 
Bob and Andrea:
Bob, I am surprised at the short time it took for you to make the change out.


Ralph
Ralph

With the engine out and the heater out and the dash on the lap, the installation of a new harness is easy and quick especially when the ends of the harness are labelled - I thought that it was going to be a daunting task, but it turned out to be quite enjoyable - much better than installing new front hubs, bearings and shims etc. which I have recently completed.

:cheers:

Bob
 
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