Changing Dials

[Guest chris brown]

Sounds daft but are you sure the spade connector isn’t for the bulb for dash lights as the earth is normally the case ie from one of the studs that have the u shaped mounting bracket

[Guest TerryBarry]

Ian,

I would have thought that the connections would be

1. Pulse from coil

2. Power for circuits in the instrument ( probably from the voltage regulator)

3. Earth - probably through the case.

Unfortunately I cannot offer any suggestions as which is which.

 

I would have thought that there must be a number of members who've used these instruments.

 

Be careful - if you reverse the connections +ve and -ve you will fry the semiconductors in the unit and it will never work again.

There is a Triumph Dolomite owner's club with a website HERE it might be worth trying a search on their discussion board.

 

Terry

[Guest Ant]

I have a dolomite rev counter in my 2B. The wiring is the same as for the original Sierra one. If your donor didn't have a rev counter then just look at the wiring diagrams for the ones which do. Mine was a 1989 2.0 EFi GLX and I know that the Haynes diagrams for that work with a dolomite gauge. I do seem to remember it using the -ve side of the coil. If I remember correctly the coil has a permanent 12v one side, and the -ve is switched (pulsed) by the dizzy / ignition unit. The bit I can't recall at all is which of these goes onto the bullet and which goes onto the spade on the rev counter. When wiring mine up I phoned a Smiths gauge supplier (Speedy cables?) and asked them. They took the code from the front of the rev counter and then told me exactly how to wire it in.

 

I guess I can crawl under my dash and check it out for you if you like, but the best plan is to phone the people who work with them every day.

 

Ant

[Guest ian luxford]

mmm the voltage regulator thing does make sense! there's a spade connector on the case that i assumed was the earth for the illumination but the fact the 2 connectors i have used are isolated from the case would be a bit of a clue that one of them isnt an earth!!! just have to hope that by connecting it straight to earth hasnt fried it! (anyone got some chips? )

if i connect it straight to live would that be ok? mainly so i can see if it does work.

rest of it looks good though

[Guest ian luxford]

thanks ant that helps i will give someone a call tomorrow least i can then connect it up properly and then see if it works!

fun this isnt it!

[Guest Ant]

If this fries it then don't blame me!

 

I've just had a look at some scribblings I made when I wired mine up. The case needs to be earthed, the spade connector is an "ignition positive" - ie +12v whenever the ignition is on, and the bullet connector goes to the -ve side of the coil.

 

I did do this scribbling about 12 months ago now so I hope I've interpreted it correctly.

 

Ant

[Guest ian luxford]

thanks for looking for that i appreciate it and dont worry i wont blame you got a feeling i have already fried it anyway!

will let you know tomorrow night hopefully

thanks

[Guest brummy-ade]

If you have knackered it theres always ebay loads of smiths rev counters on there at a reasnable price sometimes

[Guest ian luxford]

YAY!!!!

it still lives!! everything is good in the world!! all works except......

on the original dash there was just one light for the indicators but 2 feeds ( left and right) i was hoping putting the two together for the new light would work but that just brought on boths sides. i can just add a 2nd indicator lamp but would prefer just the 1 as it looks better anyone know how i can do that?

thanks for your help

[Guest Guy]

Stick a diode in each of the wires with the line pointing towards the lamp, this is assuming that the other side of the warning light is 0V.

 

If you have just 1 flasher unit, surly you can use a feed from that!

[BigLee]

Slightly different question, but thought this forum was suitable.

 

Have just bought RH S7 with Dolly dials. Rev counter is set up for 4 cyclinder but engine is xr4i 6 cyl. Dees anyone know if these Smiths rev counters can be re-calibrated?

 

Alternatively was thinking of obtaining Triumph 2500 or GT6 rev counter to replace as should already be compatible and should look the same.

 

Any advice welcome.

[Guest ian luxford]

mmm more problems....

finaly got everything working so today went for a short drive to put a smile on my face but found out i havent quite got things right!

when i reved up to 3500 the battery warning light came on and wouldnt go off again. if you kept it under those revs it would be fine but soon as it hit that point on it came! anyone any ideas? tomorrow i will be disconecting things in turn to try and work out what it could be but if anyone could save me some time i would appreciate it

[Guest daveg]

Ian

 

My guess - you have connected the battery warning light to the voltage reg instead of switch 12v

 

Lee

 

I don't believe you could recalibrate it! You need a 6 cyl rev-counter

 

Dave

[Guest ian luxford]

ok it is sunday so that means head scratching day!

firstly i dont have a voltage reg should i? also on the volt meter there is 2 insulated conections i had connected 1 live one earth but from i have learnt from the other dials i doubt this is right but what is the other connection for?

have got the indicator light working now though

[IanS]

Volt meter should be reading the battery voltage.

So one end of the battery is earth therefore one end of the meter to earth.

The other end goes to the battery, but as you do not want it to flatten the battery if left standing for some time it is connected through the ignition switch.

 

A lot of these meters are hot wire as this damps the reading. These do not care which way round they are connected and so they have 2 insulated terminals.

 

The voltage changes the reading of things like the fuel and temp guages, this is a square law, so small voltage changes give noticable changes in guage readings. Therefore a voltage regulator is the norm for electrical type guages except voltmeters.

 

ian