Wiring harness/Loom check

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Murrayminor
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Wiring harness/Loom check

Postby Murrayminor » Mon Aug 12, 2019 9:31 pm

Good evening
My 1965 2 door Minor "Gracie" is off the road for some much needed body repair work.
Tonight I decided to remove the wiring harness to evaluate its condition and generally check it was ok prior to beginning any welding.
Well pardon the pun but I was shocked how bad the harness was,it had chafed through to the visible wires in a number of places.
The harness running across the front cross member had all but cut through to the visible inner wire.
I thank the stars I looked at it and more importantly It didn't catch fire.
So not to sound too alarmist but take the time to have a root round and check the state of your wiring harness.

Dermot.
Proud owner of my first Morris Minor

JOWETTJAVELIN
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Re: Wiring harness/Loom check

Postby JOWETTJAVELIN » Tue Aug 13, 2019 12:20 am

The outer wrapping, usually fabric, binding the bunch of individual cables together usually wears through in time where it rubs against the body. That can be sorted with pvc insulation tape and moving it away from the rubbing point if possible. But exposed copper conductors through wear or any other fault need urgent rectification.
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Murrayminor
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Re: Wiring harness/Loom check

Postby Murrayminor » Tue Aug 13, 2019 6:24 am

Indeed, I had to remove the heater hose from the engine bay and noticed where the loom runs behind the bracket on the inner wing had not only rubbed through the outer wrapping but had begun to actually work its way through the wires themselves.
These wires are normally out of sight.
I suppose given my car is over 50 years old it is to be expected, but I was alarmed to see how close it was to causing major issues.
For peace of minds sake I would take a few minutes to thoroughly check your own wiring loom.
Proud owner of my first Morris Minor

ianmack
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Re: Wiring harness/Loom check

Postby ianmack » Tue Aug 13, 2019 10:07 am

The cloth outer covering isn’t very durable and I think it was mostly for holding the wires together for ease of assembly. If it has deteriorated it can be replaced with modern plastic sleeve, either in tubular form if the end is accessible or coiling around if not.

JOWETTJAVELIN
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Re: Wiring harness/Loom check

Postby JOWETTJAVELIN » Tue Aug 13, 2019 1:00 pm

Aye, cloth binding was ditched in favour of pvc tape in the late 1950's/early 60's. You can buy new fabric covering if you want to keep it looking right, I think Autosparks sell it.
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IslipMinor
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Re: Wiring harness/Loom check

Postby IslipMinor » Tue Aug 13, 2019 3:57 pm

Autosparks will recover/re-braid your harness using exactly the same colours as the original. Not cheap, but not silly either, and they will cover whatever you send them, so any additions, modifications can all be incorporated and look like they were there all along.

Excellent service the 2 times I have used them.
Richard



Murrayminor
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Re: Wiring harness/Loom check

Postby Murrayminor » Tue Aug 13, 2019 8:08 pm

IslipMinor wrote:
Tue Aug 13, 2019 3:57 pm
Autosparks will recover/re-braid your harness using exactly the same colours as the original. Not cheap, but not silly either, and they will cover whatever you send them, so any additions, modifications can all be incorporated and look like they were there all along.

Excellent service the 2 times I have used them.
Now then there's a point, would it be better to have my old harness rebraided or buy a new modern harness?
Are the modern harness made of the same material and gauge?
Proud owner of my first Morris Minor

IslipMinor
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Re: Wiring harness/Loom check

Postby IslipMinor » Wed Aug 14, 2019 10:54 am

Autosparks also provide a new harness to the original specification by chassis number. I believe they will incorporate additional circuits as well.

https://www.autosparks.co.uk/finder

Your 1965 Minor will have PVC covered cables with a coloured braiding. Unless it has suffered physical damage, the basic harness will probably be fine to re-use, but is likely to need some new terminations and bullet connectors (unless you are very lucky!).

Probably worth looking at each option?
Richard




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