Early bay Fuel Gauge Trouble shooting

[1FineOLD69]

Hi First let me apologize if this has been covered previously I couldn't find a thread for my exact problem.

I have a 69 bay window. My fuel gauge always reads empty.

One time last year when I filled the tank up full to the top, the gauge all of the sudden read about half tank.

However the gauge hasn't moved in a while and always shows empty. These days with fuel prices I just keep putting about 4 gallons of gas in there whenever I think it might be close to empty.

I am wondering where I should start to trouble shoot what the problem is, Like hopefully its something wrong with the gauge rather than something inside of the tank itself.
_________________
Looking for a complete sink unit for early bay window

[aeromech]

You’ll find the sender wire coming out of the lower passenger side firewall. There should be a connector at that point. Ground the wire that goes up front. Turn on your key. If your gauge jumps to full then you can assume that the gauge is ok but the sender isn’t.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[busdaddy]

Find the brown wire that emerges from under the lower right corner of the tank access panel, it's just in front of the voltage regulator. There should be a disconnect there, ground the end that leads off to the right and down into the main harness, your fuel gauge should read full with the key on.

If that test proves successful the sender needs repair, don't bother with any "new" senders, they will fail in 6 months (if they even work right out of the box), the only way to do the job once is this way: https://www.thesamba.com/vw/forum/viewtopic.php?t=629435&highlight=sender+repair
If you don't want to drop the engine to reach it you'll have to cut a hole: https://www.thesamba.com/vw/forum/search.php?searc..._chars=200 . If you've never been behind the tank panel now may be the time to replace all the vapor and filler hoses anyway, unless you plan on posting a topic about fuel smell or puddle with a full tank in the near future.

Isn't owning a 53 year old vehicle fun!?
_________________
Rust NEVER sleeps and stock never goes out of style.

Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!

Слава Україні!

[SGKent]

if you are not comfortable repairing the old sender, see if you can send the part to and pay Telford Dorr to do it for you. He is in San Diego if you get down that way.

In the meantime get a cheap small notebook, fill the tank and write the mileage down. Then drive 100 miles about and fill it again. Divide the number of miles by the gallons of gas and that will give you a MPG. Then you can estimate how much is left at any point by how many miles you have traveled. Unless the bus sits a year at a time with the same tank if gas you'll do yourself a favor by keeping the tank near full. It will reduce the chance of rust from humid beach air in Santa Cruz.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[aeromech]

I second the idea of keeping your tank near full. That said, try not to top it off. Topping off can can havoc with your vapor system.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound