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wiring loom bj8
- Thread starter SUPERPOT
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Keoke
Great Pumpkin
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SUPERPOT said:can anyone advise the best way to install a new wiring loom on a bj8?
The loom looks mighty big to go through the bulkhead holes!
is it best to go from engine bay into car.---
While I do not like the technique you can split the large grommet and then hide the split at the bottom of its mounting hole if you need to.--Keoke
any help appreciated,
regards,
Superpot
Bob_Spidell
Yoda
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I've done this. The wires will go through the scuttle--you don't have to split the grommet. Just work them through carefully.
The scuttle/bulkhead is a good place to start, and work outwards to the headlights, stop and 'parking' lights (maybe save the instrument cluster for last--you might have more confidence and technique). Replace one connector at a time. If the old harness is in good enough shape you can match up the colors, if not it'll be trickier (part process of elimination). Either way, you need a schematic to confirm things--there's a good one in the shop manual. Be careful to make good connections, the bullet connectors can fool you (wouldn't hurt to put dielectric grease in the connectors). It would help a lot if you had a lift (we had a pit). If any doubt test the circuits with a DVM before going hot, else you let the smoke out of the new harness. Make sure all the ground points contact some clean, bare chassis metal. Don't recall if there were bare wire connections--brake switch, maybe--but it wouldn't hurt to lightly tin the bare copper.
Most of the clamps are accessible, except I recall one on the inside of the transmission tunnel. I couldn't get to it until I pulled the drivetrain, in the meantime I just tied the harness leg to the old clamp with a tiewrap.
Last aftermarket loom we got--for a BN2--was perfect.
Oh, disconnect the battery first.
The scuttle/bulkhead is a good place to start, and work outwards to the headlights, stop and 'parking' lights (maybe save the instrument cluster for last--you might have more confidence and technique). Replace one connector at a time. If the old harness is in good enough shape you can match up the colors, if not it'll be trickier (part process of elimination). Either way, you need a schematic to confirm things--there's a good one in the shop manual. Be careful to make good connections, the bullet connectors can fool you (wouldn't hurt to put dielectric grease in the connectors). It would help a lot if you had a lift (we had a pit). If any doubt test the circuits with a DVM before going hot, else you let the smoke out of the new harness. Make sure all the ground points contact some clean, bare chassis metal. Don't recall if there were bare wire connections--brake switch, maybe--but it wouldn't hurt to lightly tin the bare copper.
Most of the clamps are accessible, except I recall one on the inside of the transmission tunnel. I couldn't get to it until I pulled the drivetrain, in the meantime I just tied the harness leg to the old clamp with a tiewrap.
Last aftermarket loom we got--for a BN2--was perfect.
Oh, disconnect the battery first.
Keoke
Great Pumpkin
Offline
Hi Bob, that was some good info. However, there are bare wires used at the fuse box and in this particular case they should not be tinned, This is because the solder will cold flow due to the pressure of the screws which causes the wires to lose good contact in the holders, thus producing intermittent circuit operation.--Fwiw--Keoke
andybj8
Jedi Hopeful
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Superpot
Thats all very good advice, the only thing I would add is to lie your old harness out and as well as checking everything is the same I would add the cable clips using the old one as reference, also fit the bullets that will be missing from the new loom, its a lot easier on the bench (ie triple for wiper motor, some doubles for headlights etc will also be missing).
https://www.austin-healey3000.com/electrical.htm
The other thing is to make your mind up if you want the proper panel light bulb holders as the new loom will have modern ones with push in bulbs rather than screw in (that means re-soldering on the old holders to the new loom).
Also dont forget to take a picture as reference for the tacho loop on the white wire, you will need to reuse the plastic bracket from your old one.
cheers Andy
Thats all very good advice, the only thing I would add is to lie your old harness out and as well as checking everything is the same I would add the cable clips using the old one as reference, also fit the bullets that will be missing from the new loom, its a lot easier on the bench (ie triple for wiper motor, some doubles for headlights etc will also be missing).
https://www.austin-healey3000.com/electrical.htm
The other thing is to make your mind up if you want the proper panel light bulb holders as the new loom will have modern ones with push in bulbs rather than screw in (that means re-soldering on the old holders to the new loom).
Also dont forget to take a picture as reference for the tacho loop on the white wire, you will need to reuse the plastic bracket from your old one.
cheers Andy
GregW
Yoda
Offline
Hi Superpot,
When I replaced my loom, I spread it out on the ground with a wiring diagram and ohm meter. I checked every circuit and then labeled it so it would be easier to install once it was in the car. Doing this helped me route the loom as well as attaching wires to components. Color wiring diagram can be found HERE
When I replaced my loom, I spread it out on the ground with a wiring diagram and ohm meter. I checked every circuit and then labeled it so it would be easier to install once it was in the car. Doing this helped me route the loom as well as attaching wires to components. Color wiring diagram can be found HERE
Bob_Spidell
Yoda
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The way I did it was to replace a section at a time, with the old loom in the car. Cut out a section then replace with the new (unless you want to save the old loom intact for some reason).
I just checked my BJ8 with original voltage regulator and fuse box; the connectors are all spade lugs.
I just checked my BJ8 with original voltage regulator and fuse box; the connectors are all spade lugs.
Johnny
Darth Vader
Offline
All good advice, Superpot. I've installed two wiring harnesses and have learned the following. One, don't remove the grommet from the harness, (The grommet comes installed on the harness from British Wiring). Two, I start from under the hood and work the wires towards the gauges first. Gather only a few at a time, it would help to have someone under the dash helping. Work the harness inside until yu come to the grommet, then slip the grommet into the opening. It's important to bend the harness where necessary before installing the grommet, other wise it'll popout. You'll have to twist and bend the large harness under the hood to locate the wires properly. Don't fit any clips on until you have all the wires in place. If I recall there's some wires that are in separate harnesses above the OD relay, and from the WS wiper motor that need to fit in the clips as well.
Good luck with your project.
Good luck with your project.