Triumph Repair: Fuel sender alignment on Spitfire 1500, fuel guage, spitfire 1500

Question
The fuel guage on my 1980 Spitfire reads about 1/2 a tank low (i.e. when the tank is full, the guage shows just under 1/2 full).  I've been told by the previous owner that the sender unit is misaligned.  Do you have any tips on how to align the sender unit in the fuel tank so that the guage reads properly?

Answer
Jim,

The sender is keyed so that it should only be possible to fit into the tank in the correct orientation.

What is possible is that the plastic float on the end of the sender arm has failed, allowing gasoline into the float.

Drive the car until you know you have less than 1/2 tank of fuel remaining.  The ideal situation would be to drain the tank completely.

To remove the sender unit:

1) order a new gasket for the fuel sender unit
2) Move the car to a safe location where spilled fuel or vapors will not cause a hazard
3) disconnect the battery
4) remove the spare tire
5) remove the board at the front edge of the trunk to expose the gas tank
6)  make note of how the wires are connected to the sender unit.  A digital camera picture will keep you from pulling a thousand hairs later.
7)  gently remove the sender retaining ring.  This is done by tapping on the ears inside the ring, using a hammer and either a large blade screwdriver, a piece of rod stock or a piece of flat stock.
8)  remove the fuel sender unit.  You'll have to turn and twist it a bit to get it out.
9)  From there, check things out.  If the float has gas in it, it's time for a new float.  I don't believe that they are available separately, although you might find another Spitfire owner with used float in the collection.   Sometimes people try to repair the floats but since gasoline will dissolve quite a few of the common sealants it's an iffy proposition.  

Otherwise it should be fairly obvious how the sending unit should be oriented in the tank.  I'd be curious to see one improperly installed...

Keep in mind when you put it all together that gasoline is a liquid with great penetrating power... so it likes to leak past old seals.  After you put the sending unit (or a replacement) back in place be cautious the first time you refill the tank to make sure it's not leaking from the gasket.


Cheers,

Jim