Before you pull hair rebuilding or locating a 'new' sender, remove it from
the tank. It is a little finicky but easy to do. The sender is held in place
by a metal pinch-ring. You need to twist the ring off counter-clockwise. I
use a wide flat-blade screwdriver positioned on one of the tabs on the ring
and tap the screwdriver with a block of wood. Keep at it and the ring will
twist off. Once off the sender can be removed - you may have to gently pry
it off the rubber seal - but dont tear the seal.
You will need to snake the sender out as the float is attached to an approx
12 inch long stiff-wire arm with a bend in it towards the float end.
I suspect you will find that the float is shot. Depending on which unit you
have the float will be either tin or plastic. I have had poor luck with the
plastic ones - they develop a crack along a seam, fill up and no longer
"float". The plastic ones simply snap into a hook at the end of the
stiff-wire arm. You can get a replacement plastic float from Nisonger's
BUT..... The last one I got from Nisonger's failed less than a year after I
An alternative is to use a brass float from an old Ford. Suggested supplier
is MAC Antique Auto. Ford number is COAZ-9202-B ($5). MAC also sells a
slightly improved version - part number: COAZ-9202-SW ($12).
These brass floats are a close but not exact snap-in fit into the hook at
the end of the stiff-wire arm. Just take care when attaching so you dont
puncture the brass float. Check by putting the installed float in a pot of
warm water - look for bubbles.....
The tin float can be repaired with solder after thorough cleaning.
Once repaired I find it good practice to dip the repaired float into
RED-KOTE to seal it for good. Recommend refinishing gas tanks with red-kote
- have had great results for the past 12 years I have been using it.
The electrics of the sending unit are not too easy to repair. But they can
be cleaned easily. Remove the two screws that hold a cover plate on and
clean it with spray-on carburetor cleaner - don't use a brush or you might
break the tiny wire. You will understand once you take the cover plate off.
After cleaning, you can apply some electrical contact lubricant/cleaner
available from Radio Shack.
It is easy to confirm the unit is working with an ohm meter. Move the arm
and the resistance should change smoothly over the mechanical range.
Unfortunately, I dont recall the resistance range.
When reinstalling, suggest coating the rubber seal with some non-hardening
(white) gasket sealer.
From: Mike Michels [mailto:firstname.lastname@example.org]
Sent: Thursday, July 22, 2010 1:35 AM
Subject: [Tigers] Fuel tank sending unit
Anybody know a source for a Tiger fuel tank sending unit or how to rebuild
one? Mine gives an open circuit (zero voltage to the gauge) below about a
quarter of a tank and reads about two gallons low throughout the range above
that. According to Stu Brennan's very helpful article on gauges and sending
units, I'm quite sure the gauge itself is accurate. It may be that the float
is heavy, but I haven't taken things apart yet to check it.