Finally got my hands on an original clubman tacho after running a wog box 5" monster tacho in its place.
Should've been a simple plug and play as that's what my car is designed for... However I have a mysterious extra plug on this new tacho!

Very poor quality image but hopefully you can make it out.
This is my old tacho:

This is just empty where the plug is on the new one and the wire is soldered internally instead of coming out.

I presumed it was an extra earth wire, but if I wired up it to the earth the car wouldn't start!

What is this extra plug for! Tacho isn't working with or without it plugged in!

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.

I have have deleted what I said before to make sure I do not confuse you any more because of conflicting replies. Make sure you use same type of Tacho that matches your car's wiring. as there are quite a few different ones and they connect differently. Check where the Tacho wires on the car are connected to and what feeds you are getting there first. Then you will know if the Tacho you are using will match the existing system on your car.

_________________
DID I MENTION THAT I AM THE BEST SUPPLIER FOR MINI ELECTRICAL PARTS AND REPAIRS?
"Let us remove your "SHORTS"

Sorry kinda confused still!

You are talking about top photo right? That's the one I'm trying to install.

So far it's spade goes to back of speedo, ie positive from ignition
Bullet goes to coil neg
Earthed by bottom screw to circuit
The red circled opposite bullet is what I'm unsure of?

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.

From memory there are two type of tach fitted.
Early loop type where ignition goes to tach and then to positive coil. Twin bullet type conector. If no tach fitted these would be conncted together to complete the ignition circuit.
And later model which uses a single wire to actuate the tach. The second one pictured.
Im sure someone will be able to confirm this.

Black leyland workshop manual has wiring for Clubman GT early type tacho.
Cheers Rob.

Edited for clarity.

_________________
82 BJ42 just completed resto
64 850 Modified(about to start rebuild)

The small pic is a current sensing type and the large pic is a voltage sensing type.
There are 2 types as mentioned above. Early cars had a current sensing tacho and later cars had a voltage sensing type. The male and female bullet connectors (circled in red) are in series with the coil. There should be 2 white wires (white is ignition positive to coil) going to the tacho. One from the ignition switch and the other going to the coil. The one you are trying to fit is a current sensing type. If you are trying to fit it to a car that had a voltage sensing type or no tacho at all then you will probably need to run some additional wiring to make it work.
IIRC the colour of the tacho needle is different on the 2 tacho types, red or white.

Hope this helps
RonR
68 MK1 Cooper S
72 Clubman GT project

_________________
68 build Mk1 Cooper S
72 Clubman GT project. Total restoration required

Really appreciate the help!!
I'll consult my black book and see if I get any further.

The ignition positive goes to the spade connector Im 99% sure, and the earth should be done through the PCB.

I'll have a play around with where the final female bullet goes! I'm sure someone in the world has installed one!
(Hopefully the PCB are compatible... Only earth and light though so shoulddddd be fine...)

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.

Current sensing appears to plug into + side of coil rather than neg... Would I then run the female bullet to earth or back to neg coil

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.

I don't know the system specifically, but, anything that is "current sensing" either needs some sort of inductive pick up, or, as seems to be the case here, must be connected so that all current flows through it i.e. in series.

If your car isn't currently wired that way, you'll need to change it to make the tachometer work. The only power feed to the coil has to be the one coming from the tacho. If there is a direct feed to the coil, then your tacho is connected in parallel and will never work if it is a current sensing type.

To answer your question above, neither to coil neg or earth. It must go to coil positive, and it must be the only ignition powered wire to go to coil positive.

Really appreciate your help Howey!!
Think ill have to re install my other huge tacho for now
Just had my coil wired up with a relay by an auto elec so last thing I feel like doing is messing around with that!

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.

Wiring can be scary but if you change your mind about hooking up the Tacho
the diagram below should help.
You would only have to take out the positive feed from the relay to the coil and reroute it to the Tacho as below.




Cheers Rob
Edited to add loom Legend

_________________
82 BJ42 just completed resto
64 850 Modified(about to start rebuild)

Rob that's is awesome, really really appreciated!

_________________
1975 Clubman
1152cc, 40dcoe weber, RE83 cam, GRed head.