fuel sender hanging

[spatz]

Hi folks, my right fuel sender seems to hang and wonder if there is a fix other than replacing it.
I am driving mainly on the left fuel tank, and when this is empty and I switch on the right tank which has then
about 33 liters left, my gauge is always reading 0. I expect The 7 liters that are missing travel through the connection
hose at the top to my left tank because once I fill both tanks up both fuel senders are 100%.

[outotheblue]

If you are using a digital/numeric gage it could be it is programmed not to accept sudden changes in signal from the sender. Fuel gages also use a real long refresh rate to damp the reading, else you would see the numbers constantly changing and the gage would be unreadable.

[Gulf LS3]

are you running a stack spatz?

[spatz]

no digidash2, but the problem is not in the dash, the other sender of the left tank works ok, the right however whenn full is 100% and when a few liters are missing
it reads 0%, so I guess it is stuck in top and not moving downards with the fuel level, or whatever else. I have to measure the resistance next time.

[spatz]

ok found the bug, embarassing one. Was reading the level from the non active tank.......my switch that is engaging the valves is also flipping
between the (Double pole single throw toggle type) fuel senders and when I actually was driving on the left tank I had the reading of the right tank.
I now also understand why the tanks was actually empty when I still had 69% reading and why it was going down so slowly. Howeve we know now that the tank link hose is actually feeding 30% to the other tank.

[Swiss_Toni]

A question in a similar vane, I have the old style analogue gauge and when the tanks are full the gauge doesn’t read full.

Is there away to “adjust” the fuel senders?

[Steve_D]

Swiss_Toni said:

A question in a similar vane, I have the old style analogue gauge and when the tanks are full the gauge doesn’t read full.

Is there away to “adjust” the fuel senders?

The fuel sender is just a float that goes up and down the tube so adjustment is not possible. There may be something you can adjust on the gauge.

Steve

[Swiss_Toni]

I'll have a look at that but I think both tanks are reading differently.

May be the float is getting stuck.

[Steve_D]

Swiss_Toni said:

I'll have a look at that but I think both tanks are reading differently.

May be the float is getting stuck.

You did remove the transit pin before installing the sensor?

Steve

[Paul.B]

Another thing to remember! If you have a balance pipe the guage will not show full on the second tank when you switch from an empty tank to what you thought was a full tank.

[spatz]

yep, as stated earlier, approx 8 liter of the fuel travels throught the balance pipe, so when you switch to the "full" tank it is reading not full.

[Swiss_Toni]

No balance pipe or shipping pin (it works but just doesn't read full).

Maybe should take the sendor out an see if it's hanging up on something or nees a bit of "physical" adjustment.

[spatz]

are you using the ultima gauge or something else ?

[Swiss_Toni]

Just an Ultima gauge, nothing fancy.

[spatz]

is that also the case when you are filling both tanks up ?

[V8 Vum]

Not wishing to hijack this thread ...a quicky qessie:

At rest ie no current, can anyone tell me which tank is 'on' using the std Ultima valve unit? Left or right (viewed from the back of the car)???

cheers

Keith