fuel gauge a bit lazy

[pickled_foot]

hi,
ok have a new problem, not a car stopping issue but one i want to resolve before it gets the better of me.
the fuel gauge on my '78 viva gls (with seven dial dash) is only ever showing about half the correct amount.
i guess it could be the sender unit which i could just replace if i can find one. but thought it could also be the voltage stabiliser on the back of the dash ( am not sure of part number). does any one have any input on this, and any idea where i would find a replacement and MAKE IT FIT.

well be good to get any ideas.

thanks.

[Firenzaboy]

Are your temperature guage and volt meter behaving themselves?
if they're working ok (ie same sort of readings as normal),i would rule out the voltage regulator and go for the sender.
Try taking the wire off the sender and earthing it to the body with the ignition on (obviously );if the guage is ok it should read full as theres now no restriction on voltage (which is essentially all the sender unit does);if this is so then i'd say sender unit - if still not ok then could be a bad connection/short on the wiring either between guage and power source,or guage and sender end in boot....
Hope this helps,Dave C.