Voltage Stabiliser - Vitesse Mk2

[Paul H]

Hi the fuel gauge on my Vitesse Mk2 has a mind of its own and from reading on tinternet its either a bad earth, the voltage stabiliser or a duff sender . The gauge never over reads and regularly goes to zero then back after 15 mins or so . Currently its under reading by 1/4 of a tank . This issue has been around for the last 18 months 

The earth is fine , so need to change the Voltage stabiliser to see if this is the culprit  - ive purchased one of the digital ones . Getting the speedo out is proving very difficult so asking if I can locate the stabiliser in a more accessible  place and rewiring.

The temp gauge is a modern type with a thick cable sender and pretty sure is independently wired so not relying on the voltage stabiliser  . 

Lastly is there a test to check the sender is ok or otherwise - would prefer to check with sender in situ 

Paul 

[Chris A]

Last year I replaced the voltage stabiliser on my 13/60 with an electronic one. I left the old unit in place and just wired in the new one and let it hang loose 

[dave.vitesse]

There are three tests for the sender units on the later cars fitted with the fuel/temperature bimetal gauges and a voltage stabiliser. Full/Hot, Half/Normal, Empty/Cold and with three resistors you can test their accuracy, just substitute each resistor in turn for the sender unit.  The values are as follows-

 

Full/Hot  =      20 Ohms.

Half/Normal = 72 Ohms.

Empty/Cold =  270 Ohms.

 The original voltage stabiliser unit has to be earthed, screwed to the rear of the speedo. Some of the modern replacement also need an earth, but not all. I would read the instruction.

Dave

[dougbgt6]

I agree with Chris, it's so light you can leave it to dangle. The original is earthed by bolting it to the speedo.  The electronics have a plastic body and three wires, 12v in, 10.5v out and an earth wire. An earthing point is easy to find behind the dash.

Doug

[Chris A]

I earthed mine to a steering column bracket. Much easier than the back of a dial. 😀

[Gully]

My solid state electronic one needed to be attached to something to earth it - I simply unscrewed the clamp knurled nut from the accessible side of the speedo, popped the stabiliser onto the thread the ran the nut back on. Works a treat.

Gully

[Chris A]

2 hours ago, Gully said:

My solid state electronic one needed to be attached to something to earth it - I simply unscrewed the clamp knurled nut from the accessible side of the speedo, popped the stabiliser onto the thread the ran the nut back on. Works a treat.

Gully

That is what I intended to do but I dropped the knurled nut, hence why I used a steering clamp. I couldn't find the nut anywhere, until today. I was rummaging about behind the dials, as one does, and the nut suddenly fell out of where it was hidden. It is now back on the clamp. 😘

[JohnD]

I've posted this so many times, one more won't hurt.

Temp sensor response, with some faulty ones as well.  The X-axis is degrees C.

 

[dougbgt6]

And this has to do with voltage stabilisers because………………?

Doug

[Paul H]

Update 

I was preparing to add new Voltage Stabiliser to feed the Fuel Gauge and I thought Id try another Gauge and the replacement Fuel Gauge works .

Need a full test to prove but so far so good . Normally I find the problem much later down the checking / replacement process 😄

Paul 

[Prince Brainier of Meccano]

I was concerned with overheating so I put my temp sensor in a pan of boiling water, left it to be at temp for a while and then measured the resistance.

While this was warming up I earthed  the sensor wire through a resistance box and with the engine running, set the resistance to put the needle just into the red at the end.

For mine I had to add resistors in series with the sensor to make it the same as "tested" value for boiling hot.  I then knew that with the needle in the red it was at unpressurised boiling.  The readings came down on the gauge and weren't so alarming.