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TR2/3/3A Wiring Harness Question[s]

ckeithjordan

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I’m installing a new wiring harness from Autosparks (in the UK). It’s really well-engineered and a work of art. So here’s my question (there may be others):

Should the leads to/from the regulator, solenoid and fuse box exit the main trunk of the harness from the engine bay side of the firewall opening, or be on the interior side, with the leads themselves passing through the opening? I’m aware that the other engine bay connections (brake lights, dynamo, horns, front lights, etc.) have to pass through as well.
 
From inside out, the difficult part is getting the grommet and wires through the hole. I used a funnel from the dollar store and cut that down to fit and fed them through.
steve
 
Thanks Steve. I didn't do a good job of framing the question. See attached photo of the harness. To the left is the bulk of the harness, ie, the gauge leads, tail lights, dipper switch leads, and the lead to the left-side of the engine bay (lights, wiper leads, coil lead, etc.). To the right is the lead to the solenoid, brake switch, lights, etc.). So, my question is should the firewall hole be at the left red line or the right red line? You can see that I've anticipated it being on the left, as I've squeezed everything through a grommet, which will line the hole. Is that the correct location?

IMG_5462.jpg
 
Looks correct to me, are you going to feed the wires from the engine bay into the cockpit and then deal with the grommet? I believe I might have put the grommet in first and feed the wires from the inside out.
 
Something looks wrong, are you going to feed the wires from the engine bay into the cockpit and then deal with the grommet? I believe I might have put the grommet in first and feed the wires from the inside out.
 
I’m going to feed the wires from engine bay into the cockpit, the various smaller “limbs” are all smaller diameter and the grommet will be the last item in. I didn’t see how it was possible to to feed them the other way ‘round, as they were larger, plus trying to feed all those leads looked difficult. It’s interesting in that the grommet suggested has a smaller center hole; I’m using one of the frame grommets which has the largest opening and it’s snug around the harness at this point.

Thanks again for your help.
 
That area is tight with all the Y and using one of those other grommets might be great. I will try a picture but I am having trouble.
Anyways if you did it that way wouldn’t your gauge wires be on the wrong side of the firewall
 
If I remember right, the wires between the tie wraps are those going to the voltage regulator...so that would be outside the firewall, while the remainder goes inside. Is that what you are asking?
 
If I remember right, the wires between the tie wraps are those going to the voltage regulator...so that would be outside the firewall, while the remainder goes inside. Is that what you are asking?

Yes. I looked at a lot of photos (including yours way back when) and couldn't tell. I assumed that they were, but then I thought, maybe not. The attached photos show where things go, as far as I can tell, I'm just looking for confirmation that the firewall grommet is in the right location.

IMG_5463.jpgIMG_5464.jpgIMG_5465.jpg
 
Ok for sure it is correct now that I see the larger photo, and it looks like a better way than I did it. The only thing I see problematic is the grommet fitting. I fought mine having the grommet in first--- then using a funnel through the grommet to stretch the grommet out on the inside and fitting the wires from the inside of car out.

Good look you will get it
 
My Kit TR3 came with a brand new harness and as I was adding an alternator I undid the harness and added heavier wires also remove the generator wires. It was a pain to get the grommet through the bulk head. As far as I remember dish soap is your friend.

David
Wires through bulkhead.jpg
 
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