petrol gauge problem!

[Budgie]

Hi there , rite here goes , petrol gauge has been working fine , i take out the speedo to change a bulb and leave the speedo resting on the aperture while i turn on the ignition to check that the bulb i replaced lights up, fuse gets blown, so i change the fuse put the speedo back in place everything now works fine except for the petrol gauge which now only shows the tank to be half full when the tank is filled to the brim so basically its only showing its half capacity at any one given time, the car is negative earth, any suggestions would be gratefully received as car electrics are not my strongest point

[bmcecosse]

Can only guess that during the 'short' the voltage regulator has been damaged due to passing excessive current....

[Budgie]

ah right i see so how do i go about sorting that one out then in so much as do i need a new gauge/regulator etc?

[bmcecosse]

Indeed I would try another voltage stabiliser. Someone has a link to a very inexpensive one from Maplins (for -ve cars only).

[SUE482]

What is the year of manufacture of your car, the mechanism of the fuel gauge operation is completely different between the "Gold faced" and "Black faced" speedos. If its gold faced you require an earth to the case as well as the two connections at the rear to function correctly.

[Budgie]

its a 1969 model,strange how everything else works fine , there again i'm no electrical fan , so what and where is the voltage stabiliser situated

[bmcecosse]

Back of speedo - beside the fuel gauge...... It ONLY supplies the fuel gauge - so yes everything else will still work just fine !

[lambrettalad]

it's rectangular in shape

[Budgie]

ah i see of course duh thanks for the info folks i'll see if i can purchase one from esm or did someone on here get one from Maplins if so how much do they cost and what doi ask for seeing as its an old car ?