Fuel

Ashley · Post by **Ashley** » Fri Apr 06, 07 6:40 pm

Anyone know if these a firm in the UK that recalibrate's fuel tank gauge's ???

Fitted a new sender unit, when the tanks full the gauge read's half

Thanks.

Anonymous · Post by **Anonymous** » Fri Apr 06, 07 7:37 pm

I have this problem with the Satellite. I just put it down to old wiring and crroded connections causing resistance in the circuit.

I always keep a couple of cans of fuel in the boot on long journeys just incase.

Dave-R · Post by **Dave-R** » Fri Apr 06, 07 7:58 pm

Ash. It is either a bad earth (the strap over the rubber part of the line out of the tank is the usual problem) or bad live connections as Fingers has suggested.

However the low voltage regulator/limiter in the dash that powers the sender may not be up to much.

You sure you have the correct sender?

Dave-R · Post by **Dave-R** » Fri Apr 06, 07 8:13 pm

I tell you what Ash.

See if it goes to full deflection if you take off the wire from the sending unit and earth it to good clean metal on the chassis.

If the gauge goes to full, then all is well with the electrical system and it is the sending unit that is not right.

If it still only goes to half then check the sending unit has a good earth.

Next thing to check is the voltage regulator (limiter) in the dash. The output voltage should be pulsing from 4- 9 volts. The average voltage is about 5 volts.

Ashley · Post by **Ashley** » Fri Apr 06, 07 10:52 pm

Dave, checked the fuel gauge, earthed the feed it go's straight to full, so OK there

The feed to the sender is OK, the earth from the sender OK

The sender is brand new so shouldn't be a problem there

The only thing i haven't checked is the limiter, were under the dash will that be and how do i check it ???

Dave-R · Post by **Dave-R** » Fri Apr 06, 07 10:59 pm

You already checked it. If you got full deflection when you grounded the wire to the sender then everything is OK. It must be the sender itself.

I have the ohm specs for empty and full on the sender someplace. I will see if I can find it.

Dave-R · Post by **Dave-R** » Fri Apr 06, 07 11:04 pm

Here it is;

With the float in the 'empty' position you should get a reading of 73 ohms (+/- 12 ohms).

In the full position the reading should be 9.6ohms (+/- 1 ohm).

So the sender should be what they call a 70 ohm unit.

Matt · Post by **Matt** » Fri Apr 06, 07 11:07 pm

I hear that this is a common problem with the new senders , which are often wrong out of the box .

Ashley · Post by **Ashley** » Fri Apr 06, 07 11:10 pm

So can i take that reading from the sender unit out of the car Dave ???

Dave-R · Post by **Dave-R** » Fri Apr 06, 07 11:27 pm

Yes. Take it out of the car.

Anonymous · Post by **Anonymous** » Sun Apr 08, 07 5:52 pm

could it not be the float on the wire arm bent in the wrong position?

latil · Post by **latil** » Sun Apr 08, 07 6:04 pm

My original would only read 1/2 the scale. When I tested it I got 9.8ohms full position but no reading after around 40 ohms. Gently cleaned the resistance wire and got full scale correct reading to 73 ohms empty,theres not some protective coating on a new one ?

Ashley · Post by **Ashley** » Mon Apr 09, 07 9:16 am

Thanks fella's, Look like the float was in the wrong position, did some adjusting and its reading just over 3/4 full when the tank is full, i can live with that

Thanks again fella's

Anonymous · Post by **Anonymous** » Mon Apr 09, 07 11:28 am

Got the same prob with mine, just can't be bothered to strip the sender out & bend the arm. Most senders are havin this problem.