GT6 Mk3 gauge failure

[euan douglas]

If both my temperature and fuel gauges have ceased to work am I right in assuming the likely cause is a failed voltage stabilizer?

Anything else I need to look for and is the stabilizer fixed to the back of the speedo?

Thanks for any help.

Euan

[Casper]

Yes and yes.

Consider a solid dtate one from eBay

C.

[Yakooza2]

Hi

I bought this from Ebay for my Spitfire and it works a treat, easy to install too.

 

http://www.ebay.co.uk/itm/Instrument-Voltage-Stabilizer-Stabiliser-Regulator-solid-state-/380747658712?hash=item58a65435d8:g:BYMAAOxyWt5SYDbN

 

Nader

[AidanT]

The ones sold by paddocks look the same as the originals and are a straight swap and are actually solid state. Easy to swap and all the solid state advantages

Aidan

[dougbgt6]

I wouldn't say they were easy to swap, you need the old triple jointed wrist!    My solid state one dangles behind the dash, the original still attached to the speedo.

[euan douglas]

Doug

Does it not need to be earthed by screwing to something?

[dougbgt6]

No, the electronic ones have three wires, one of which is earth. The other two are 12 volts in and 10 volts out. So you can connect it anywhere you want, really.

[AidanT]

????. Quite right Doug, easy if you remove the speedometer though!!

 

Aidan

[dougbgt6]

Aidan, yes easy to remove the speedometer, it's getting it back in that's the problem!

[Pete Lewis]

Most triumph under dash work also needs a tin of sticky plasters, strong tea bags and a cushion

and upside down varifocals

pete

[AidanT]

I'm double jointed

[Colin Lindsay]

you don't need arms, just tentacles.

[JohnD]

OR,

Afuse.  It's the same one as supplies the O/drive if you have one, and the OE wires to the gearknob switch short out to the stick, because they are insulated only with shellac.

 

John

[euan douglas]

Thanks for all the thoughts  -  I'll get a new unit and then worry about how to fit it!

[dougbgt6]

But will it be electronic or the old clockwork type? We have to know.

[euan douglas]

Well  -  you may well chastise me but I've plumped for the direct replacement as offered by Rimmers.  Let's hope it works!

[AidanT]

It will be interesting to see if it's solid state or the original type Mine was not described as solid state but turned out to be. Mi e gives a very stable voltage output the original type does move up and down a little

 

Aidan

[Pete Lewis]

And the only reason you need a stabilised voltage on thermo bimetal gauges is that the variation in battery voltage whilst charging and dischaging while driving , will change the gauge readings , keeping the voltage an average constant keeps the gauges reading the same whatever the cars charge system is producing

 

The older moving iron gauges has two opposing coils which balance any votage variations and a magnetic needle they are not votage conscious

 

pete

 

 

on

[dougbgt6]

I would only advise you that I originally replaced mine with the old type from a reputable source. It lasted two weeks. I got my money back and bought an electronic one, it's now 4 years old. There are, of course, some dodgy electronic ones, there should be more "bits" than just the sold stat regulator, additional capacitors etc.

 

http://www.ebay.co.uk/itm/SOLID-STATE-VOLTAGE-STABILIZER-FOR-CLASSIC-CARS-/131860660056?hash=item1eb381ff58:m:miTOdRHgGhIrgcmJaV06YQgc

[euan douglas]

Got the replacement stabilizer today though whether it is solid state or not I don't know  -  looks just like the OE one - how can you tell?  However I checked the gauges today and both are working perfectly, so I don't know what's going on.  I think I'll leave replacing the stabilizer until they both fail once and for all.

 

When it comes to it I suppose the best way of getting at the stabilizer is to remove the central instrument panel which will give better access to the back of the speedo as even seeing up in there is impossible never mind working at anything!

 

In the meantime many thanks for all the feedback.

 

Euan

[dougbgt6]

You can only tell if you saw it in half!

 

Yes central panel out, hand around the back of the speedo, undo the nearest nut, it's round and knurled (is that the word?) DON'T drop the nut, ease out the clamping mechanism, DON'T drop it. Engage double jointed wrist, move to the further nut, do the same again. Ease out the speedo, undo speedo cable, whole thing comes out and there it is, the voltage stabiliser!

 

If you thought that was difficult, wait till you have to put it all back!

[JohnD]

A multimeter will tell all.

 

The OE "stabiliser" is far from its name, as its output is 12V - 0V - 12V - 0V - etc, in a way that averages 10V.  The slowly-reacting, highly damped gauges behave as if it were a continuous 10V.

 

A modern solid sate stabiliser's output is ... 10V.

 

 

The OE is a little tin can, whose base is a piece of circuit board.

  

 

 

A solid state one is usually 'potted' in a small plastic casing

 

Of course, some originality fanatic might put the second inside the first, but there's nowt so odd as folk.

 

John

[euan douglas]

Well, out of curiosity I emailed the stabilizer manufacturer (Caerbont Automotive in Wales) and asked if it was solid state or bimetallic.  The reply was that it is "an electronic 10volt regulator", so that would seem to suggest it is as JohnD's last photo and just as Aidan T said.  So hopefully a lot more reliable that the OE one. 

 

Euan

[Pete Lewis]

The originals are always deemed unreliable ,, pity they only lasted 40 years

 

by pure cost effectiveness you are unlikely to manufacture the old thermo bimetal and points type with electronics being so cheap these days , its not feasible without lots of £££

[euan douglas]

The gauges have stopped working today, a day of high temperatures so I wonder if that has a bearing on it?  Also the wipers don't work at the same time as the gauges so is that usual in that the stabilizer affects them and if so then what else is likely to be inoperative?

All help gratefully received!