'73 MG BGT - diagnose fuel gauge probs

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Mon 16 Jul 2007 10:23
'73 MG BGT - diagnose fuel gauge probs - FrankSm
Hi folks

Have a wonderful 1973 MGBGT - the fuel gauge has recently started dropping to "E" despite the tank being either full or partially empty.

Since the dash & guage is easy to get at, I though I'd start there - assuming the fuel gauge is a simple volt meter, would anyone happen to know what voltage range the guage works off ? ie. what is full, and what is 1/2 ?

Other than that, I'll trace the wiring to the sender and maybe have a look at the sender itself removed from the tank. Possible the contacts on the sender unit are dirty or rusty.

Thanks in advance

Frank

Frank Smyth
'95 Vauxhall Omega CDX 2.5TD
'96 Mazda MX5 1.8 turbo

Edited by Dynamic Dave on 11/11/2008 at 23:56

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Mon 16 Jul 2007 11:21
'73 MG BGT - diagnose fuel guage probs - jc2
With a voltmeter or even a bulb,check there is a supply to the gauge-if there is a voltage regulator as there usually is, it will be less than 12v and will usually go up and down as the voltage regulator cuts in and out.If there is voltage,go to the sender-remove the gauge wire and repeat the check for voltage-if it's there,the next thing to check is the earthing on the tank-if this is bad or non-existent your gauge won't workHaving exhausted all these,it must be the sender.
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Fri 20 Jul 2007 08:29
'73 MG BGT - diagnose fuel guage probs - FrankSm
Thanks !

Wiring checked out okay continuity-wise - since parts for the MG are cheap, and the sender is easy to get at (they located it on the side of the tank right behind the rear wheel where it can gather mud LOL) I shall put a new one in.

Cheers again

Frank
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