• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

What is correct wire harness outer wrap

red57

Jedi Knight
Country flag
Offline
It seems like most of the new wiring harnesses available are cloth wrapped but the 1960 BT7 I'm working on has wire harnesses wrapped in black vinyl tape.

I bought the car in 1987 and there was no evidence of prior restoration when I got it so I always assumed the wire harness was factory. I prefer a black vinyl wrapped harness because I can add new circuits like driving lights and wrap with vinyl tape and it all looks uniform - if I use the cloth wrapped harness, any added circuits will be obvious.

Does anybody know how to identify which type of outer covering for which years/models of car?

Thanks,
Dave
 
HI:Dave

I have seen wire harnesses wrapped in cloth predominantly on original cars, additionally I have seen what I think are after market ones wrapped in blue vinyl

I have not seen replacement harnesses wrapped in black vinyl

Wrapping a harness in a non breathing outer cover will further reduce It's current carrying capability
 
Black Bicycle handlebar tape (cloth version) might be an option
 
Thanks for the replies. As I said, I bought the car in 1987 and it had a black vinyl wrapped harness that appeared to be factory.

Keoke, I haven't heard about capacity restrictions from vinyl wrapping (all the American cars of the 50s thru 70s I've had were vinyl wrapped). I actually figured cloth was a poor choice for road dirt and holding water along the bottom of the car??

BigGreen, The tape you are referring to, I think is what I used to know as friction tape and you are right, if I have a cloth wrapped harness then it would match better than typical PVC tape.

Steve, Finding cloth covered wiring isn't the problem. I'm more interested in why I have a car with vinyl and most suppliers only offer the cloth. The only supplier I have found
offering optional vinyl wrapped is SC Parts here:
https://www.scparts.co.uk/sc_en/bri...nd-dashboard/wiring-harness/harness-8690.html

The real question is did the factory use vinyl wrapped harnesses and, if so, when & on what models - heritage cert says nothing about this and I can't fined anything in Clausager's Original Austin-Healey.

I'm not going for concourse but have become curious.

Thanks,
Dave[FONT=Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif]
[/FONT]
 
Keoke, I haven't heard about capacity restrictions from vinyl wrapping (all the American cars of the 50s thru 70s I've had were vinyl wrapped). I actually figured cloth was a poor choice for road dirt and holding water along the bottom of the car??

Well Dave Lucas Was doin the Engineering N he had some unique ideas---:highly_amused:

A more accurate reason is:
wire's current handling capability is determined on a individual wire basis in free space , consequently when we bundle , wrap in PVC, enclose in sleeving we alter its operating environment which lowers it's current carrying capability.
 
I'm not sure it this pic came thru I was trying to enlarge it so you could read it. It is from Anderson & Moment and shows the woven fabric on the BT7 just as Steve's source says. Anderson & Moment says nothing about any distinction between cars and only discribes that the harness had black woven fabric with a yellow fine line cross hatch on it. It also says the rear harness was all black woven with no cross hatch.
 

Attachments

  • img479.jpg
    img479.jpg
    88.6 KB · Views: 131
I'm not sure it this pic came thru I was trying to enlarge it so you could read it. It is from Anderson & Moment and shows the woven fabric on the BT7 just as Steve's source says. Anderson & Moment says nothing about any distinction between cars and only discribes that the harness had black woven fabric with a yellow fine line cross hatch on it. It also says the rear harness was all black woven with no cross hatch.

Thank you vette. I think you have solved the mystery for me. Apparently a PO must have rewired the car sometime prior to 1987 - a lot can happen in 27 years..... I know it had been re-painted at least 3 times so who knows what else it had gone through.
Anyway, I will proceed with a cloth wrapped harness. I'm not going for concours, but I'm probably better off doing what the factory did in this case.

Thanks to all for the help.
Dave
 
I'm not sure it this pic came thru I was trying to enlarge it so you could read it. It is from Anderson & Moment and shows the woven fabric on the BT7 just as Steve's source says. Anderson & Moment says nothing about any distinction between cars and only discribes that the harness had black woven fabric with a yellow fine line cross hatch on it. It also says the rear harness was all black woven with no cross hatch.

The next page has a chart with color trace descriptions.
 
The next page has a chart with color trace descriptions.

Yes it does but I wasn't sure if the print would be large enough to read and it is mostly redundant to what was just said including the supplier that you linked to would surely show what was needed. Since I was trying to enlarge my other pic I didn't want to add to the size of my up load. But I think I got now.
Bye the way if it can be seen, this pic shows the harness as it should b strapped to the off side inner structure brace.
 

Attachments

  • img480.jpg
    img480.jpg
    88.4 KB · Views: 136
All original 100's had fabric covered wiring except for the one from front to back along the chassis rail for the rear lights. It is vinyl wrapped for protection.

Years ago the only replacement wiring was vinyl wrapped. I think that might be what you have.
 


Well.....Lucas Was doin the Engineering N he had some unique ideas---:highly_amused:


A more accurate reason is:
wire's current handling capability is determined on a individual wire basis in free space , consequently when we bundle , wrap in PVC, enclose in sleeving we alter its operating environment which lowers it's current carrying capability.

Yes, current handling capacity is determined by the wire size, shape, and composition. The real issue, however, is heat (something you generally don't have n non-Lucas 12V automotive systems). You bundle tightly, heat builds up, you start having issues with current handling.

NOT because they are bundled.

If so, all those 60-pair Key System phone lines would have burned up last century.

And, that's mostly AC...and we're DC.....tightly bundled never made a difference. However, if you are worried about Lucas heat and the possibility of smoke escaping, probably a wiring tray would be best, where one wire going up in a mushroom cloud won't affect the rest.
 
All original 100's had fabric covered wiring except for the one from front to back along the chassis rail for the rear lights. It is vinyl wrapped for protection.

Years ago the only replacement wiring was vinyl wrapped. I think that might be what you have.

I used non-adhesive harness tape to wrap the wire for the rear lights (just couldn't leave the fabric exposed down there). Not sure if it's technically correct for a Healey, but it's period correct:

https://www.amazon.com/Factory-Electrical-Adhesive-Harness-Friction/dp/B06Y2KDQRN
 
You bundle tightly, heat builds up, you start having issues with current handling.----YEP
 
Hi Dave,

Although it is obvius that you can purchase a new harness, back in the '80s, I sent my original harnesses to have them rewrapped by (I believe) British Wiring with the original woven pattern (fabric). Since my harnesses were electrically in good condition but looked weathered, having the haranesses wrapped greatly improved its look and also retained the original bends making reinstallation much easier. Although I can't remember the price (and it would not be relevant if I could), I can tell you it was quite a bit less expensive then purchasing new harnesses.

It's an alternative you may want to consider,
Ray(64BJ8P1)
 
I replaced my BT7 wiring with a harness from Moss in 1980. It is wrapped with black vinyl tape.
And it was not exactly correct, but I made it work. Still does.
Good luck.
Douglas
 
Concur with RAC68, back in 1977 when I restored my 1960 BT7 I had the original harness recovered with the original fabric with the yellow tracer. Was done by a company called YNZ Yesterday's parts, which at the time was out of his home garage about a mile from where I was living. He subsequently opened a real shop and is still quite busy and has a nice website. If I recall he charged me $35 at that time. You can see some of the harness in this picture. He knew exactly what it needed when I showed it to him. He told that 22 year old kid (me) to take it home clean it thoroughly by removing all the fabric, cleaning the wires and then putting electrical tape every six inches to keep it together in the correct shape.
 

Attachments

  • 104-0448_IMG.jpg
    104-0448_IMG.jpg
    65.3 KB · Views: 140
Back
Top