[Healeys] Convex rear view baby mirror and fuel sender adjustment

[BJ8 Healeys]

Fred, the sending units are not adjustable electrically.  Adjustments are
made in the calibration of the  fuel gauge.
Smiths fuel gauges for Healeys register full when they sense approximately
95 - 107 ohms, and empty at about 3 - 4 ohms.

There is a procedure for calibrating similar gauges used in MGAs at
http://mgaguru.com/mgtech/electric/fg_06.htm.  The technique for calibration
is the same, but you have to use 95 - 107 ohms instead of the 68 ohms used
by the Jaeger gauges in MGAs.
I determine the resistance values needed by measuring (with a full tank)
between the green/black wire to the T terminal on the back of the fuel gauge
and ground.

Calibration of the gauge is not difficult with the MGA procedure (but
somewhat tedious, with trial and error), but there is one caution:  to
adjust the gauge it is necessary to loosen the two small nuts on the back of
the gauge so that the threaded posts can slide in the slots.  On the inside
of the gauge where you can't see them is a plastic "foot" that also slides
in the slot and prevents the coil of tiny wire around the post from turning
as you loosen/tighten the nut.  If you are not careful to prevent the foot
from coming out of the slot (keep outward tension on the post when the nut
is loose), when you tighten the nut again you'll spin the post and coil and
break the wire.  Then, the gauge will have to go to a professional shop for
repair.  Trust me.

Steve Byers
HBJ8L/36666
BJ8 Registry
Havelock, NC  USA

-----Original Message-----
From: healeys-bounces at autox.team.net [mailto:healeys-bounces at autox.team.net]
On Behalf Of Fred Wescoe
Sent: Wednesday, July 18, 2012 4:14 PM
To: healeys at autox.team.net
Subject: [Healeys] Convex rear view baby mirror and fuel sender adjustment

List,

I happened to be in Kmart today, for totally unrelated reasons, and came
across an item, in the automotive isle, that I purchased.  The item is a
"baby mirror", intended for parents to be able to observe a child in the
back seat area. .  It is a convex mirror, 2 1/2" x 5",  black and attaches
to the windshield with a mechanical suction cup.  It has an unlimited,
adjustable range.  It was $8.99.  I tried it as soon as I got home and it is
terrific for a rear view mirror that simply attaches via the suction cup to
the upper windshield.  Great view to the rear that I have never had.

Some time back, someone was working on a fuel tank sending unit and trying
to adjust it for proper readings.  What is the final advice on what the ohm
reading should be?  How are the readings taken and how is the adjustment
made?

TIA,

Fred
63 BJ7