More wiring questions

[tmc]

This is follow-up to earlier posts about my wiring project. I've laid the harness out in the car and starting to ID where each wire goes, labeling them, etc. I have several questions at this point, some of them naive, I'm sure!

1. The harness has a number of wires that end at blunt connectors. It appears to me that I have to create the wiring between those connectors and various components.......like the horns, front signal lights, the steering column harness, the brake switch on the right front chassis, etc. To keep to "original", I need to match the wire colors to the harness I have......any suggestions?
2. There's a grommet that seals the hole where the wiring harness comes through the firewall......how to you fit the grommet over the harness, other than slitting it?
3. I have a heavy brown wire, with a little green slip on "tag" that extends forward and also appears with the cockpit portion of the harness......can't find that wire anywhere on the wiring diagrams. All the purely brown wires seem to be accounted for between the fuse box, ammeter, and starter solenoid.
4. The wires that end "bare" need to be "tinned"......I take that to be solder to hold them together and not fray?

 

[jclay]

Wiring Codes

 

[Geo Hahn]

Sorry I do not recall what car you have, my harness work was on a TR3A with screw connectors (not Lucar), perhaps yours is similar since you mention bare wires...

1. The harness has a number of wires that end at blunt connectors. It appears to me that I have to create the wiring between those connectors and various components...

There are sub-harnesses that may come with some kits or may be available from some suppliers or you may make yourself or you may reuse the old ones if they are okay.

I think I did some of each. Thinking back these included the wires to the control head, to the headlamps, the daisy chain to speedo & tach lights and the grounds for the instrument cluster.

I alway keep an old harness around to have a supply of correct coler wire. You may even be able to salvage some wire from your old harness if it is not corroded.

2. There's a grommet that seals the hole where the wiring harness comes through the firewall......how to you fit the grommet over the harness...

As I recall I was able to squeeze the harness thru there. It was a tight fit was getting the harness thru the firewall hole w/o damaging it -- for that I made a cone out of milk bottle plastic and used it like a funnel to slip the wires thru the tight opening.

3. I have a heavy brown wire, with a little green slip on "tag" that extends forward and also appears with the cockpit portion of the harness...

No idea off hand since you say you have the wires to & from the ammeter accounted for.

4. The wires that end "bare" need to be "tinned"......I take that to be solder to hold them together and not fray?

That's what I did, just tinned the tips so the rest of the wire could have some flexibility.

 

[Banjo]

Many of the components those blunt wires go to have "pigtails", or short runs of wire coming out of the component that also end in a blunt connector. you join them together with those rubber covered barrel connectors. Single barrel will join 2 wires, the double barrel ones will join up to 4.

 

[TR3driver]

This is follow-up to earlier posts about my wiring project.

Always best if you mention what car you are working on. I know you've got a TR3A in your profile, but it's not unusual for people to be working on a different car (or have more than one).

The steering column harness should connect directly to the main harness, using the sleeve connectors that others have mentioned above. Note that originally, some of these connections used a 6 opening sleeve which is NLA. But it was effectively just three 2 opening connectors in a special rubber sleeve, so you can replace it with three 2 opening sleeves.

For the others, I'd suggest ordering either the subharness or the color coded wires from British Wiring

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]2. There's a grommet that seals the hole where the wiring harness comes through the firewall......how to you fit the grommet over the harness, other than slitting it?
[/QUOTE]Make sure you've got the right grommet with the large opening. You should be able to carefully slide it along the harness (before installing the harness of course) to the right position.

Sorry, no help on the brown wire. Maybe you should ask Moss.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]4. The wires that end "bare" need to be "tinned"......I take that to be solder to hold them together and not fray? [/QUOTE]That is the idea, but at this point I am not convinced whether it is actually a good idea or not. If the wire vibrates at all (and there is a lot of vibration in a TR3) the strands will flex right at the edge of the tinning and eventually break. I tinned most of the underdash connections on my TR3A, and some 15 years later discovered that some of them were broken almost entirely. The factory untinned connections seemed to last much better.

If you still want to tin the ends, I would suggest stripping back the insulation a bit more (perhaps 3/16"), tinning back to the insulation, and then installing some heat shrink tubing to help reinforce the transition between tinned and untinned. You can see here where I did that for the ammeter connections in my 59, and 6 or 7 years later they were still in good apparent condition (of course, the heat shrink would hide any damage).

 

[hondo402000]

If you want to get some really good heat shrink tubing, get it from a marine store, the heat shrink tubing used for boats has some kind of hot glue inside and when you shrink it it also make a water tight seal and will not come off!

Hondo

 

[TR3driver]

the heat shrink tubing used for boats has some kind of hot glue inside and when you shrink it it also make a water tight seal and will not come off!

If you don't happen to have a marine supply nearby, it's also readily available from Amazon, MMC etc.

The tubing with the higher expansion ratio is also handy when you want to seal/insulate different sizes, like a quick connect or several wires joined to a single wire.

 

[swift6]

There are a few choices for Marine shops in the area. We may be in landlocked Colorado, and be classified as a high altitude desert in northern Colorado, but we have quite a few resevoirs and quite an active boating community in the area. McMaster Carr is always a good source to point out though.

 

[tmc]

Sorry about that. I forgot to mention I'm working on a TR3A, TS45911. The old wiring harness is long discarded.

 

[tmc]

Thanks for your reply and the photo. Very helpful.

 

[tmc]

The pigtails I have are too short, non-existent or too ugly. I have the various connectors, etc. on the way from Moss, but sounds like I need to contact British Wiring.......maybe should have done that earlier.

 

[tmc]

Thanks for the help. The picture is getting clearer............

 

[tmc]

Thanks. I have a good wiring diagram from British Wiring, with the codes printed on it.

 

[tmc]

There are a few choices for Marine shops in the area. We may be in landlocked Colorado, and be classified as a high altitude desert in northern Colorado, but we have quite a few resevoirs and quite an active boating community in the area. McMaster Carr is always a good source to point out though.

Thanks. I live in Loveland, Colorado myself.

 

[tmc]

If you want to get some really good heat shrink tubing, get it from a marine store, the heat shrink tubing used for boats has some kind of hot glue inside and when you shrink it it also make a water tight seal and will not come off!

Hondo

Thanks for the tip. I have some heat shrink from NAPA, but the marine stuff sounds much more effective.

 

[tmc]

I apologize for the disjointed replies.......I can see I used the wrong reply method, which doesn't attach to the post I was replying to. Have patience with an old man, as I get better at this.

The posts have all been very helpful. I've procrastinated on the wiring project because I could see it was going to be tedious and that I would feeling my way around like a man in a blackened room. Luckily the wiring in a TR3A is fairly simple compared with a modern vehicle, so I'm confident I'll figure it out. I need to go look at well restored TR3A and look closely/take pictures of the wiring before I go much further, that I can see.

Thanks again for your help. I'm sure I'll be back for more!

 

[swift6]

I need to go look at well restored TR3A and look closely/take pictures of the wiring before I go much further, that I can see.

I know of a few in the area that you could look at. Have you hooked up with the local British car club? The British Motoring club of Northern Colorado? Their first meeting of the year is coming up next week in Fort Collins.

PM me if you want more details.

 

[tmc]

I need to go look at well restored TR3A and look closely/take pictures of the wiring before I go much further, that I can see.

I know of a few in the area that you could look at. Have you hooked up with the local British car club? The British Motoring club of Northern Colorado? Their first meeting of the year is coming up next week in Fort Collins.

PM me if you want more details.

Yes. We went to the annual meeting/dinner at Rodizio Grill late last year.

 

[Geo Hahn]

...I need to go look at well restored TR3A and look closely/take pictures of the wiring before I go much further...

Or better yet a grungy but original example. That may be a better source as many good-looking restorations will vary from what the factory did.

For example, I once took some pics of a nasty looking TR3A that had original wiring -- dirty to be sure but very neatly routed:

Also note that the firewall layout changed quite a bit along the way... at TS60000 if I recall rightly.

 

[angelfj1]

You might consider doing what I did, and use an intermediate terminal block which allows you to extend all of the circuits and have access to take voltage readings. This is attached to the bottom of the scuttle sump with strong magnets.