Sunday, 7 February 2021

FHC resto nr. 121; Choosing wiring harnesses part 2


Another of the plans that fell victim to the everlasting restoration of this early TR7. In the spring of last year I selected the main harness that was going to be used for this car. But then the parts car, I received from a friend late last year, intervened. And the wiring from that car looked to be even better than the one I had chosen before. So over the weekend I spent some time in the shed to check and compare the various wiring harnesses I had put aside for the ’76 car. And after an hour or so I was left with these harnesses that got my approval.


Pictured above is the main harness (PKC 1946), engine harness (RKC 5511), facia harness (RKC 4348), plus battery lead, battery earth and rear screen earth. And finally two door harnesses (TKC 3831). Though only one will be (partially) used as this car will get the early roof mounted interior light. But the passenger door will get a map reading light. So that is a part of the harness that will be used after some extra attention.
The gear box harness (UKC 9200) and the body harness (RKC 3630) are not shown above, as these have been prepared already. I even had a go at cleaning the various connectors somewhere last year, but forgot to make a mention here. For cleaning I used a solution of salt, dissolved in hot water and cleaning vinegar. After leaving the connectors in this solution for 15 to 20 minutes they were rinsed of with clean water. And finally dried in the bathroom, being the warmest and best vented room in the house!


Remains one final task before I commit myself to changing this car’s wiring to the later layout. And that is to make the decision if I am going to do a job I should  have done before painting the shell: Enlarging the hole in the firewall, through which the main harness passes into the engine bay. On this early car the diameter of the hole is approximately ø43mm:


But on the later cars from which I want to use the wiring harnesses, this hole measures approximately ø62mm:


I had hoped to get away with “just” using the earlier grommets for the passages through the bulkhead and into the front wing. But removing one from an old loom intact has proved to be impossible without butchering a complete loom. And with no guarantee that the grommets would survive fitting it to a different harness. So I have decided to enlarge this hole. Remains to find out how best to tackle this job. For that I will pick the brains of a few friends as soon as possible!
Another looming challenge are the different locations for the engine harness to exit the cabin. On the ’76 car this harness passes through a hole in the transmission tunnel.


Where on the later cars the engine harness passes through the bulkhead alongside the heater.


As these holes are pretty close together I hope I can use the original one. Maybe I have to adapt the engine loom a little for this. But that shouldn’t be too much of a challenge!

And to end this weekend I took my Defender out to play for a few hours in the snow, ice and mud!

No comments: