10 replies to this topic

[Boab]

I have spent all day making sure that the dash I made fiited like a glove. All the gauges, switches and clocks wired up neat and tidy. Reconnected the battery to find out that the only thing to work on my new clocks were the lights.
Fuel & Temp, speedo and tacho did not budge. These clocks have a different 'wiring plate?' on the back to the one I had on originally. (Green faced 120mph 1275GT/Cooper?)

1. Should it be a straight swap?

2. Connecting the tacho with the bullet and spade connector, is there any other wire to be considered?

3. Does it need the small metal box with the 3 spade terminals under the speedo and fuel/temp clocks. What is it for?

4. Can anyone supply me with the correct, detailed set up to add these clocks?

Thanks in advance.

[Boab]

I just noticed the search button, and found this by DAN

If you have Smiths clocks then you just need the rev counter pod and three clock binnacle, brackets and trim boards. The PCB is different but it only supplies lighting and earth to the rev counter so you can do without it by jumping in wires to the main pod. If you have the late (90 on) Nippon Seiki clocks it is a little harder as the two and three clock versions are quite different with the three clock being in one piece rather than two pieces as in the Smiths version. You can fit the smiths rev counter to the end of the Nippon two clock but it doesn't look quite right and doesn't fit exactly. Also the arrangement of the PCB is different. So if you have the Nippon it is easier to fit the whole three clock unit, with brackets and binnacle.
As has been said, some cars have the wiring present and some do not. It is a pair of wires which will be taped back into the main loom near the main clock connector if it is there. If they are not there they are easy enough to fit. The tacho you will most likely find is the three wire type. One 12v instrument feed (not regulated), one earth and a coil trigger to the spare negative coil terminal. Instrument lighting is also needed. You should try to use the right colour wires if you can get any. I would avoid using the four wire version of the tacho (in case you find one) as it means cutting about your ignition system quite a bit.



Sorry, but this is still not very clear.

Should there be 2 or 3 wires and where do they go to FROM the clocks.

[Dan]

What was your car originally? What year was it built and do you know where your new gauges came from? The metal can is a voltage stabiliser, it's needed to keep the fuel and temperature gauges callibrated.

[Boab]

It is a 1983 mayfair originaly 998cc. I have no idea what the clocks are off. The ones I would like to use are the 1275GT 120mph. The voltage stabilizer was not in, but is now (1.45am, and I've just come out of the shed. I must get a life ) I have 5 sets of clocks to mess about with, but as you have said previously, I need to find the correct calibration. I was thinking of stripping the original speedo and replace the clock faces so I still have the original running gear, if you know what I mean.

The wires I have for the tacho are W/BLK and GR/ORANGE. Looking through the Haynes, these seem to be correct for the year and model. Are there supposed to be any other wires coming from the Tacho? Haynes says no, so I would presume no.

I will check to make sure that the W/BLK goes to the neg side of the coil and that the G/O goes to the fuse.

One other quick question. I have a gauge with a battery symbol on it and blue and brown wires connected to it. (Possibly an ammeter). The gauge does not work, but if I disconnect it I get no power to the car. Will a normal clock gauge be suitable to replace it. Or can I just bypass it with a switch. Any other suggestions are welcome.

Cheers Dan

[Pavel]

If the clocks you have are from an early GT (pre 76), the tacho won't work since that electrical system wires up the tach differently.. The coil is actually supplied from the tach I believe, so if the tach is removed, the car won't run! I've had this problem and gave up with those clocks...

You could simply try finding a later tach..

The other gauges I don't know what the problem could be, but the voltage stabiliser is quite necessary for them to function properly

[Boab]

I couldn't get the 1275GT clocks to work. However, I now have a different set in and are working perfectly :grin: . Got the dash installed today as well, so it will apear on my projects page later with a couple of pics. Oohh, the bullet connector never went to the coil so I done my own connection.

Cheers

[Pavel]

Glad to hear it's all sorted! Guess you learnt never to rely on the mini's wiring to be correct:D

[Boab]

Okay, next problem. How do I wire the lights for the gauges up. I have a live feed, but thinking about it this means they will be on all the time. Which wire is the live coming out of the light switch? Once that is sorted, what about the earth? The gauges only have a bulb wire and that is it. Do I need to add an earth.

What fuse should the main lights be on. Currently 20amp, but has melted a few times.

I feel a nightmare coming on

I have just been and checked the clock illumination and found that the fuel/temp does not work. Bugger. Need to strip it again in the morning. It is also very dimmly lit. Ideas??????

[Dan]

Yup, 76 is the electrical change point and instrument and ignition systems before and after 76 are incompatible.
If you put the dial from one speedo onto the guts from another it will need calibrating (but you'll probably need your new speedo calibrating anyhow)
The clocks illumination and everything to do with them should be working off the same connector on the back of the pod.
If you're talking about lighting for additional gauges then they need power from the sidelights circuit which is Red/Green. They should need an earth but they may well be expecting to get an earth from the casing of the instrument, which they obviously can't do if they're in a wooden dashboard. Put an eyelet on a black wire and secure it under the nut for the instrument and earth it to the bodyshell earth point under the parcel shelf (or anywhere you like if you don't mind drilling holes!). The middle unit of the three clock pod does tend to be rather dim compared to the others, just because of where the bulb is.

As for the broken gauge, it does sound like an ammeter as it seems to carry all the power for the car. Are you sure it's broken? Ammeter's are pretty boring gauges and don't do a lot. Or it could be wired wrong. Myself I would trace back the wires and rip it right out and start again. DON'T earth the casing of an ammeter, if it fails internally and it's earthed there could be all sorts of fires starting. Don't put a time clock (or anything else) in it's place untill you know what it is and how it's wired.

[Boab]

Cheers Dan. The ammeter does work and it is pretty boring. I am keeping it in as I can't be arsed to take all the dash out again. How would I get the light to work on the ammeter if I do not earth it?

[Boab]

Wahey, I've done it. The wiring was already there, which is what those sets of wires were for. I did wire them up to the other set that are there but when I attached the earth the engine cut out. (would this work for a 12v outlet?????) So I tried the other ones and they worked. The ammeter already had an earth cable as part of the assembly.
I replaced the fuse box, and low and behold the everything has started to work without blowing fuses.
I'm well happy now :grin:
Back to work on Monday, then the following week I'm off again. Ideal time for working on Rab.