My neighbor just bought an '65 VW bus. The fuel gauge needle jumps around. Anyone out there with a bus that can tell me where the weak link is ; or better, point me to a wiring diagram with troubleshooting info.

Jim -

Try looking on the GoWesty & BusDepot.com websites. If that fails, have him/you call Hans Imports in HB & ask for Carl or Hans (say Tom Trischler referred if needed).

My guess is wiring, connections or sender - that's an old harness & probably cracked all over by now!

Sender, gauge, wires. One hot to the gauge, one ground, one sender wire. At the sender, one ground, one sender wire. It's scary simple. First check the grounds, then the power connections on both ends of the wire, then the sender wire connections. The tank "may" be difficult to access, and the sender is installed in the top of the tank. If it's like a later bus, you have to pull the engine to get to it. My neighbor is all over splitties, and I can ask him for any information you may need. I may also have an aftermarket manual for it (a repro of the real thing).

The Cap'n

I have had a lot of VW and every time the gauge starts to jump its the ground.

Went back over and took a few pics:

1. Wires: One black with switched 12v
One brown, it shows continuity to an unused wire in engine compartment
One gray with red stripe, no idea what this is yet or what it connets to

2. Sender:Behind the fan housing and held down with 4 bolts. Couldn't feel any
spades for wire to attach to

3. Back of gauge: Does the terminal maked "G" get the wire returning from the
sender ?

Didn't find any info at Bus Depot..

That ground terminal looks pretty rusty!

+ -> Upper left = 12 V
G -> Upper right = Sending Unit
Round stud -> Bottom center = Ground


Clean it all up and make sure that ground is connected to a good chassis ground ...
Andy

...found this sender on-line. Top looks like one in van, but I cant's see the connector here ?

There is a single spade connector just like the 914 ones, different ohms thou.
For bus wiring diagrams go on thesamba.com and look in the technical section for the right one...

Damn it Jim!

Just realized that the bus is 6V, not 12 V ...
Andy

Was 6v, now 12 volt; lots of PO changes.

Did he change the fuel gauge too? It's got 6V stamped on the housing ...

Andy

more bus photos please. this is getting me interested in getting my long stalled bus project going again!!!

cool ride!!!

FG will get changed; I'm trying to test and sort the wiring to get his project on track.

Thanks for the help, I'm pretty set.

I'l see if I can get some interior shots later. This thing cost over 9K

Take the sender out and check it with an ohm meter. The resistance should change linear and not jump around. Sometimes can be cleaned and repaired.

Nice bus!

I put my daily driver back on the road yesterday

Black is your power wire -- goes to the + on the gauge.
Brown is the sending unit wire -- goes to the G on the gauge
Grey w/ red is the illumination wire -- goes on a bulb socket into the gauge.

If he buys a voltage drop resister he can put it in between the power wire and the + on the gauge and still use the 6 volt gauge.

I'm pretty sure brown is always ground ...

Andy

Brown is the sending unit wire, black is power, grey/red is the lite....

http://www.thesamba.com/vw/archives/info/w.../bus_66_USA.jpg

Cool, that saves me from looking for it!
Jim, in answer to your PM, that diagram is what I built my bus with, so I doubt I could add much more.
Let me know.