replacing the wiring loom

[Guus]

Hi,
Searched for this topic, but couldn't find a direct hit. Since the iginition is so unpredictable in my Rover and having had a little fire in some wires a few years ago, I am really thinking of renewing the complete wiring loom.
I found a supplier for this, Autosparks, who has a harness which is quit expensive but might do the trick.

Can anybody advise me if replacing the harness is a job that can be done by a enthusiastic but not so experienced hobbyist?
Thanx
Guus

[Phil Nottingham]

Not done a P5 but have others and its no big deal if you work on it methodically. The big problem is the main loom is quite bulky and there are a lot of other bits to thread through.  This is why its expensive.

Auto Sparks is the best - its actually only a couple of miles down the road from us

[Guus]

Thanks John,
Working methodically doesn't mean removing the old one completely and after that fitting the new one I suppose... Do you know if there is a written procedure to tackle this?
Guus

[petervdvelde]

Guus,

I agree with Phil. It can be done with a lot of patience and it is time consuming. I made new wiring looms for 2 of my classic motorbikes. These are a lot smaller and less complicated then wiring looms of a P5B but the principle is the same. I took a wooden board and divided it into 2 area's. I put the old wiring loom on the board in area1 with nails to the side of the loom. Then i copied the position of the nails (especially on "junctions")to area 2. Then is removed the insulation of the old wiring loom and "simply" positioned new wires in area 2 with identical colors. I added some additional wires as i wanted to switch the lights and horns threw relays. Something worth to consider for you too. Then wrapped the loom with tape and fitted the connectors.
I also used Autosparks for buying the wires. Don't wrap the loom with tape with glue but use tape without glue. It give a much better result.

For my MGB V8 conversion i bought a new wiring loom and removed the tape to add additional wires for the relays for lights, horns and cooling fans and fitted an additional fuse box. I also needed to make some changes to the loom as several engine components were on a different position on the V8 compared to the 4 pot. I had to do this with the loom fitted to the car as i didn't have an old loom as example

attached some pictures of the work.





And the result

[Phil Nottingham]

You know how some lucky people can play pianos and other music instruments without music scores or much if any training I can do neither and that does mean nothing even though I come from a musical family.

What I can do almost asleep is, and I have been able to for as long as I can remember, is to visualize in my mind and devise electric circuits.  I never needed to write them down either but now do so I can remember what I did

Whether these be car or household its no problem and I could make a loom and fit it fast - however as with trying to play a piano if I could not do it I would buy a loom and if I could not fit it pay an auto-electrician to fit it.   I would not now try to read music or play a piano even if I would very much like to (and I would) but I know my limitations so its no problem. 

A P5 has loads of circuits for its era - nothing at all like modern cars but still not something to launch into unless you know what you are doing.

Electric cables when short circuited can burst in to flames faster than you can disconnect the battery and cause serious injury to person and property  so ensure you know what you are taking on.  The price of loose cables and the colours and grade required would be a lot of money too and you need to whether its 1 metre or 30 metres and its gauge. Manhandling it in the car without damage, getting it into place and connecting up all terninals correctly first time is crucial.

Good luck

[Guus]

Thanks Phil and Peter
(Peter, again impressive the extend of work you put in there! it indeed looks great).

I know my limitations but think there is only one way to go: replace the desintegrated loom! And I will if Autospark can not only deliver the loom but also the 'plan' on which it is based (the blueprint with colours, switches, relays and devices). This will help me enormously in the preparations.
iF this is not available, I think it will be nearly impossible.
Guus

[ernie1000]

Hi
i may be going down the same route...auto sparks loom to replace..on the website it is only for the 5b not the coupe...but suppose aside from a few extra instruments they are similar..cheers David