After spending hours getting the twin pumps working (and not filling up the boot with gasoline), I discover the fuel gauge was unemployed, ie no readings even when switching tanks.
1. I knew the tank units were OK. Checked them when cleaning & reinstalling the saddle tanks.
2. Checked ground connections for the sender units. Both OK.
3. Used jumper lead to check continuity from 12v wires from senders to change-over switch. Both OK.
4. Suspect the voltage stabiliser was kaput. Removed it and checked it independently with 12 volt battery. Reading on the 10v middle terminal indicated it was OK.
5. Checked connections to fuel gauge on printed circuit board. Got readings from both terminal on back of gauge, so I figured it was OK.
6. Checked to see if voltage was getting to change over switch from gauge terminal. Zero volts.
7. Checked plug connection (terminal #1). Discovered it was not making contact with PCB end, hence no volts @ switch.
8. Gently spread plug "tongue" with pliers, contact achieved & volts @ switch, hence volts now getting to sender units. FUEL GAUGE WORKS!

I could have saved hours of work by first checking for voltage directly at sender units on each tank, but no, I had to do it the hard way.

And in the background on the radio, Mark Knopfler was reminding me:

"That ain't working, that's the way you do it. Money for nothin' and chicks for free".

Pete

 

Well done Peter. I found most of my gauge problems were related either to the printed circuit board or (even more so) the long plug connector and the "ribbon" entry to the PCB. At present my clock has again stopped working, so I will have to get back in there sometime soon.

 

I think you were just thorough. Good job.

 

John, my clock is also there for decorative purposes.
It's funny when you hear someone selling a Jag say "and the clock even works!"

 

Hindsight is always 20/20.
I think you "dun good"
I don't see any problem with your process. No matter what problem you're facing a jumping-off point must be chosen. You dive in and start swimming ! .

Cheers
DD

 

Redtriangle, thanks for sharing!! I have a non working fuel gauge and your post was perfectly timed.

Jeff H.

 

Your'e welcome Jeff.

I wouldn't mind a dollar (US preferably) for each hour I have spent sorting electrical gremlins on my restoration!

 

I hear you!!! I'm just getting started on my rolling restoration and those gremlins are my current nemesis. My current list includes a fuel gauge that reads empty, no spark at the spark plugs, and a brake light (dash) that is always on. Still, the car puts a great big smile on my face!

Jeff H.