Vintage 140 gt cluster - no fuel gauge :(

My 142s came with a GT cluster. It's beautiful and lovely and was refurbished by Roger in FL before I owned it. Recently, it got shaken to hell and back on a couple of vintage rallies in CA.

At first, the coolant gauge and fuel gauge seemed to go all over the place together.
Then, the coolant gauge settle down and the fuel gauge stopped working all together.

I purchased a new voltage stabilizer from HiperAuto, and put it in... The coolant gauge stabilized but the fuel gauge did nothing. Next I replace the fuel sending unit.. still nothing.

When the wire is touched to a ground it does, you guessed it, nothing!

I'm just at a loss for what could be the culprit, and how I might go about testing the gauge itself (other than grounding the wire).

Here's the gauge for reference.

Image repair

Thank you! I couldn't figure out how to get it to work.

Would anyone happen to have the wiring diagram for the GT cluster?

I will check and see if one came with my NOS cluster. It may just be installation instructions...but they will be in Italian.

Dave Riedle

driedle said:

I will check and see if one came with my NOS cluster. It may just be installation instructions...but they will be in Italian.

Dave Riedle

Click to expand...

I can work with italian!

Installation instructions for the early GT cluster are already online, but there's no wiring diagram.

http://www.240.se/litteratur/282666.pdf

FYI, the pinouts are the same for a stock cluster.

Hiperfauto is indeed correct. There is no wiring diagram in the installation instructions for the early GT Instruments cluster.

Also the pinouts are indeed the same as the stock cluster.

I would test the connections to the fuel gauge directly with a rheostat to rule out a bad gauge.

Dave Riedle