21 replies to this topic

[rust-machine]

I recently purchased my 1983, 1275mini. It has a rev counter but it does not work. I am currently fitting a new dash and am trying to solve the problem whist the wiring behind the dash is all exposed. I have tested the two wires that pug into the back of the rev counter with a voltmeter and they both seem to be giving out currents. But still shows nothing on the rev counter. I even brought a new rev counter and that still did not solve the problem.
Does anyone have any idea what the problem could be here?

 

Thanks konnan.  

 

[KernowCooper]

Have to give us the make of the rev counter your trying?

[rust-machine]

The rev counter is made by smiths 

[petey81]

Have you checked the connections on the coil?

[rust-machine]

Yes, they all appear to all be good working connections :/

[petey81]

Is the rev counter earthed? Post some pics if you can.

[Craig89]

A picture of the face and reverse of the speedo would probably help here. Does the ID of the speedo (wrote on the face) begin RVI or RVC? Do you have electronic ignition fitted or is it standard points?

This info will help to find if you have the correct speedo for your car or if you have a wiring issue

[rust-machine]

Thanks for all the help. Here are some pictures

[rust-machine]

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[rust-machine]

And I believe It's just points.

[Craig89]

Right ok, standard clocks. You say you tried another rev counter...did you swap the counter in the cluster or try another complete cluster? Just trying to establish weather it could be a break in the tracks on the PCB on the back of the cluster.

If not then it could point to a wiring issue

[rust-machine]

Hi
Re rev counter / taco problem
Today linked a live feed from the fuse box
And a feed from the coil
Still no joy
Tried both tacos

Is there any way of testing the rev counter
Or do I need a find taco from a 1993 mini

[Craig89]

That is how I would test a normal rev counter but I am not familiar with this type. I have done abit of research and it would appear that it is wired like this:



1 - ground/earth
4 - 12v power for the tacho
2 - feed from ingnition switch
3 - feed to positive side of the coil

[Craig89]

So basically the feed from the ignition switch to the positive side of the coil goes via the rev counter in at 2 out at 3

[dklawson]

Craig's information is correct.  You have a Smiths RVI type tachometer, sometimes referred to as an impulse tach.  They do not wire like a modern instrument with a single wire to the coil, they get wired in series with current flowing through the ignition coil.  They are also generally not compatible with electronic ignitions.

 

If you have problems with the tach after following Craig's wiring scheme, post back with what you did and what is happening and we'll elaborate on things to check and do.