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Engine Bay Layout Question

rlandrum

Jedi Trainee
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My TR3A (41073) has a later model wiring harness (i.e. 60001+). The control box, fuse box, and a few other things all seem to have the Lucar connectors. I'm considering replacing the harness after uncovering a few oxidized wires.

I have the current one nearly wired up, and I'm noticing that the layout of the control box and fuse box and starter solenoid are too close, and that the Lucar connectors prevent me from installing them in their original locations, or at least the locations dictated by the hoes in the firewall.

Does anyone here have a later TR3A/B? Is there any chance I could get a picture of the engine bay where the control box and fuse box mount so that I might see how everything is oriented?

I'm trying to decide if it's better to buy a more correct TR3A harness (with screw terminals) and a new control box and fuse box (that might fit in the allotted space), or if I should stick with the parts I have and re-order an incorrect harness.
 
It's not a great photo, but try this from TS71909L. I seem to recall that the pre-60000 cars had horizontally mounted control boxes, but I could be wrong. If I'm right, maybe that's the big difference?

Update: looking at pix of the TR3 Nick refers to in another post, I was right about the change in control box orientation. Take a look at this photo.
 
A few years ago I restored a TR3A commission number TS36136L. Being a Scotsman, I bought a later wiring harness that was on offer from a supplier. It took me agest to cut off the connectors and solder on some different ones. I ended up also fitting a later control box to try and save some work. I would therefore always recommend fitting the correct wiring harness and other components to make life simple. You will also have an easier life in the future when it comes to replacing a fuse box or similar.
I also discovered that the wiper motor has an extra wire on later cars and there are some other subtle differences.
Below is a picture of my current TR3A TS64566L, which I hope will be useful for you.
016.jpg
 
Here's a view of mine after I did some cleaning up ...

Hope this helps.

Tom
 
Nick - our brain cells are working with split second timing again. Could be very dangerous!

T.
 
It makes interesting comparison. Pre- and post-60000 or dirty and clean! Must get back to cleaning up my engine compartment.
 
By the way, in Piggott's Original Triumph TR2/3/3A, p. 58: "The Lucas regulator and cut-out was of type RB106/1, and it was mounted horizontally on the TR2/3s and earlier 3As. However, late TR3As, probably from TS60001, had the regulator unit - now with spade rather than screw terminals - mounted vertically."

Next paragraph: "Later TR2s, 3s, and most 3As had the flasher unit mounted vertically with the connectors at the top, whereas very late 3As and 3Bs had spade connector flasher units, mounted vertically, but with the connectors at the bottom."

However, on p. 59, bottom picture caption: "The tab mounting of the horizontal flasher unit can just be seen at top left. Late TR3As and 3Bs, as shown, had the flasher unit mounted horizontally and the regulator mounted vertically."

Just wanted to make things perfectly clear .... /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Tom
 
Unless you're really on a tight budget I would suggest you go with the correct pre-60000 parts, esp on things as visble as the control box and fuse holder.

ControlBox.JPG


These parts can be had via eBay pretty cheap (except maybe the flasher unit) and when you replace the control box the old one can be your spare (or sell it on eBay to offset the cost of the screw terminal variety.

Fuses especially look good in the open holder when you use the Lucas ones.

Fuses2.JPG


Someday I will get brave and trim all that extra wire on the leads to the control box.
 
NutmegCT said:
By the way, in Piggott's Original Triumph TR2/3/3A, p. 58: "The Lucas regulator and cut-out was of type RB106/1, and it was mounted horizontally on the TR2/3s and earlier 3As.
Yet another little detail that Bill apparently overlooked; the control box was changed to a type RB106/2 fairly early in production. The change is even mentioned in the workshop manual, so it may have happened before the TR3 was introduced.
 
For what it's worth, the Lucas Master Catalogue 1945-60 shows the 37138B (RB106/1: 1954-55) superseded by the 37182A/H (RB106/2: 1956-59). The supersession means that the 37182 would've been used for replacements. That catalogue also shows the 37283D and later 37290D for the later cars. Both are RB106/2 models with the spade terminals.
 
I definitely have the holes to mount my stuff as shown in Tom's post, but I have the equipment shown in Nick's post.

I have two similar control boxes, although one says Harting, both have spade terminals.

The fuse box I have is in okay condition, but the contacts were painted white, and need to be cleaned. Again, spade terminals.

The starter solenoid I have has a screw post. The original must have had a lucar connector, since I found part of it stuck in the connector on the harness.

I have two different flasher units, both screw type, although the harness is equipped with screw connectors.

Looking at TRF, I see the control box and fuse box, both screw types, together would be more than $100. That plus the correct harness puts me at close to $400. Which is probably doable and the best option.

Also, were battery trays standard equipment? My TR3A didn't have one, and wasn't sure if I should buy one. I'm using a sealed battery.
 
If by "battery tray" you mean the plastic liner, then they were not standard equipment. I doubt you'll need one.
 
rlandrum said:
...Looking at TRF, I see the control box and fuse box, both screw types, together would be more than $100...

$75 from Moss though probably less if you watch eBay. If you get a new control box you may want to use your old cover on it as the hew ones may not have the 'Made in England' embossed on the top.

Battery trays were aftermarket items. You may find that you do not need one (I have never used one).
 
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