6 replies to this topic

[Italianjob]

Ok its starting to annoy me now,

 

Replaced my old one which would read full when the tank was actually full, once I'd used a tiny amount of fuel it would just read empty.

 

Changed it for a brand new minispares one and now it just stays at half full whether the tanks full or empty! I've removed the rubber ring thing that sits on the float as it kept working its way up the arm and getting tangled, but still no luck. I'd really love to not have to keep sucking petrol out everytime I have to check it as its rather an unpleasant taste.

 

Is there anything else that could possibly be wrong that I'm not checking?

 

Thanks in advance

 

 

[dklawson]

For the later cars there are two possible sending units.  For cars after about 1992 the float arm has a Z-bend in it.  On the earlier cars the arm is more or less straight.  If you have the wrong sending unit the float arm can bind in one position so the gauge reading never changes.  

 

Another possibility is that you have the right sending unit but you have the wires connected to the wrong terminals on the sending unit.  Look carefully at the wires.  The green/black wire goes to the sending unit spade terminal that is isolated from earth by a plastic washer.  The black wire goes to the spade terminal that is spot welded directly to the mounting flange of the sending unit.  If the green/black wire is on the sender's earth terminal the gauge will read full all the time.

[Italianjob]

Thanks for the help, I tried changing the wires over but the connectors seem to be the correct sizes for where they go. I did make a connection with them the other way round and the fuel gauge when over the full maker and stayed there, does that sound normal? My cars a '93 so bit of a crossover year. I fitted XNB10007 from the minispares site, is this correct?

Thanks in advance

[dklawson]

I cannot answer which sending unit is correct for your car... I just know that when the injected cars were introduced there was a change to the tank and sending unit.

 

As a test, turn the ignition switch to the run position.  According to what you have said earlier, the gauge should go to "full".  With the ignition on, open the boot and unplug the green/black wire at the sending unit.  Do not let the disconnected wire touch anything and watch the gauge.  If it stays at full, the gauge has a problem or the green/black wire is shorted to earth somewhere along its length.  If the gauge goes to empty, that suggests that the wiring and gauge are OK and that the problem lies with the sending unit.

 

If the test suggests the problem is with the sender, drain the tank one more time and remove the sending unit.  With the sender outside the tank, connect the wires to the sending unit as normal and turn the ignition on.  Operate the sending unit by moving its arm slowly through its range of motion while you watch the gauge.  If the gauge responds normally, this suggests mechanical binding of the float arm in the tank.  

[firstforward]

Have a read up here.....http://www.theminifo...not-full/page-2

[Italianjob]

Funnily enough I did check the sender before I put it in moving it up and down and it was fine.

 

Thanks for the link firstforward after reading that it seems I've bought the wrong sender unit and should have the injection one even though its a carb model, ill have it out later once its stopped raining and investigate! thanks for all the help, hopefully this will solve it.

[Italianjob]

Job done guys! I removed it and bent it like the injection one, refitted and as I poured in the fuel again it rose to where it should have been! Thanks so much! Hopefully this will help others too!