TheSamba.com :: View topic - fuel gauge

Fri Jul 18, 2008 11:27 pm

Hi

i have problem with my fuel guage.

I had a 61 beetle and decide to change my speedometer with a new one from cip1

i bought and a new fuel gauge sender unit

i have bought also and a fuel gauge vibrator

here is one new and one used one..

i notice that when i placed them the start getting hot and so i remove the vibrator... later i notice that the new speedometers have and fuel gauge vibrator built right in.

so i connect directly the cables to the fuel gauge.

one ground, one + , and one coming from the sender unit in the tank.

now i have this problem...

when the sender unit ( resistor ) is on the lower position - empty tank

i get this reading

when the sender unit is at the upper position (full tank)

i get this reading

any solutions please ?? what can i do to fix it...

also i notice that when i turn off ignition switch (no + ) the indicator needle stays at the same place.... if i move the sender unit in other position then after i turn the switch on again, the needle moves to the new reading.

the needle goes back to the zero position only if i remove the cable from sender unit.

Fri Jul 18, 2008 11:36 pm

I really wish I had an answer for you. But I don't. I'm replying to say that I'm impressed by the way you assembled your question though, very well done! Damn if I coulndn't give you an answer though.

One thing though, you said the needle doesn't change if you turn the key off? That's odd, it should. Unless the later model gas gauge setup doens't do that or something.

Sat Jul 19, 2008 7:18 pm

The gauge continues to register after you turn off the key because you took the positive lead off of the wrong side of the fuse box. There are two or three sending units,triple check to make sure you have the proper one. The gauge grounds through the sending unit.

Sat Jul 19, 2008 10:40 pm

proljo wrote: The gauge continues to register after you turn off the key because you took the positive lead off of the wrong side of the fuse box. There are two or three sending units,triple check to make sure you have the proper one. The gauge grounds through the sending unit.

the unit continues to show even i remove the positive cable from contact...

about the sending unit now... here is the problem... i dont know what kind of sending units are for my tank... or can i ask to see what is the correct one..

any shop or link to check??

Sun Jul 20, 2008 1:37 pm

Try Speeys Jims Home Page. click on electric fuel gauges. Good Luck

Sun Jul 20, 2008 11:42 pm

i think that my problem must be the 2 resistors that fuel gauge has inside..

they dont work well with my sender unit...

so i will probably open the gauge and try to find witch resistor will work with my sender unit (try a variety of ohm resistance )

Mon Jul 21, 2008 9:28 pm

Are you grounding the sending unit?

Mon Jul 21, 2008 9:39 pm

It looks like your sending unit is not matched to your gauge. The resistance must be the same at empty/full for both. We just ran into this problem with a customer's Autometer kit they brought in - the gauge was a 0-90 ohm and the sending unit was something like a 15 to 70 ohm. will never read completely empty or full. :wink:

It should list what the two parts are rated for on the packaging or instructions/spec sheets.