hi , the tacho on my clubman doesnt work (current sensing, 2 bullet connector's on the back). I have sourced another tacho (voltage sensing, only 1 bullet connector on the back).

How can i make this work??

Ryan

Might get more responses if you change the title to "how to install voltage sensing tacho" - which is what you really want to do...

My voltage sensing Smiths has one lead to the + (or is it -) coil terminal (the switched side anyway) and is earthed through the case. There are other leads but these feed the internal light. (But I wouldn't trust any electrical advice I provide

My initial response to teh question was "can't be done" but thought I'd look anyway....

Good luck

noted... but there must be a way to do this ?!?

Easily done.
Plug the two bullet connectors off the old tacho together as they supply power to the coil.
You will need to run a new wire from the Negative side of the coil to the new
Tacho. This is the trigger/voltage sense wire.

You will need to run a new power wire to the Tacho from the switched side of the fuse box as well.

Its been years since I have looked at a later Tacho so I'm not 100%.
But I'm think the Blade connector is the positive from fuse box switched side and the Bullet is to the negative side of the coil.
Get a second opinion from someone to confirm this for you.
Cheers Rob

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

I checked a previous post and above is correct.
http://www.ausmini.com/forums/viewtopic.php?t=80827&highlight=

I can upload a later clubman wiring diagram later tonight if you need it.
Cheers Rob

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

Thanks for your help Rob.

I took the tacho out of the cluster and replaced my old one with it. So i am running my old cluster with the replacement tacho.

I tried what you said, the tacho works - but whenever i turn the lights or indicator on, the tacho stops working. The engine is also affected and the RPM drops. The fuel gauge also doesnt work although this may be unrelated.

any ideas?

Double check the printed circuit is not broken.
Also look where the loom plugs in as i have seen bits of the copper circuit lift and fold sideways or snap off.
Also make sure the tacho earth (small screw next to blade) is good.
You can run a wire direct from ground to the tacho earth screw.
If printed circuit has bad earth the light circuit might be trying to draw earth from tacho.

Cheers Rob

Printed Circuit from minisport.com.au with earth mod

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

Early Clubman Wiring

Legend


Late post 76 Wiring

Legend


If you look at the mini spares modified circuit you can put an eyelet on the tacho earth instead of soldering an earth to the board.
(Solder a printed circuit at your own risk, not a novice job when the circuits sell for $90 upwards)

Hope this helps sort out your gremlins.
Cheers Rob

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

you were spot on rob - i ended up wiring the tacho directly to another earth / power source and it works fine. Fuel gauge also works now...

My printed circuit is really stuffed and i have been soldering wires to it , it looks terrible and its very bodgey but i have managed to get all lights etc working. EXCEPT for 1 problem, the left indicator does not work when the lights are on The indicator light, come on permanantly when the lights are turned on. However this may not be related to the instrument cluster i guess.

PM `convertible mini' if you want a new PCB.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.