[Spridgets] fuel senders and ethanol

[w swift]

I purchased a fuel sender unit from Moss a few years ago and installed it
in my Bugeye after restoration in very late 2015.  Had it on the road for
about a month before garaging it for the winter (unheated garage). Drove it
most of 2016 summer/fall months. Away for winter agin in unheated garage.
Pulled it out of garage a couple weeks ago and took it for some shakedown
runs. Found problem, solved it and I think I know what caused it ...

During shakedowns, I found my fuel gage to be erratic hovering about empty
but occasionally oscillating up and down a bit.  I read the excellent
descriptions of Smith fuel gage operation by

 Barney Gaylordhere  :http://mgaguru.com/mgtech/electric/fg_01.htm

And began a diagnosis.  Gage (original Bugeye) removed, tested, checked out
fine. Resistances measured and compared reasonably well with is article.

Checked resistance from G/B lead to sender and ground got very low figures
- i.e. tank near empty. Dipstick measurement said 3/4 full.

Removed tank and pulled sender.  Plastic float nearly full of ethanol.
Should be empty.  If it's full it doesn't float, it sinks to the bottom of
the tank and rests near "empty" unless you slosh the tank by rocking the
rear end, then it will move a bit - which is what I saw on the gage.

Winter in NH means variable temps between about 70F occasionally and -20 F
occasionally, maybe 60 days below 32 F.  That's the temperature that water
(in ethanol or most other places) freezes.

I believe the freeze/thaw cycles during the winter caused the plastic float
to crack and leak, slowly.  I removed the plastic float from the lever arm
(seen here:

http://www.mossmotors.com/graphics/products/PDF/980-004.pdf)

I located a minuscule crack in the circumferential groove where the lever
arm snaps onto the float.  I think that during extended periods of below
freezing temps, ice accumulates on the wire ring that snaps onto the
plastic float (air inside) and basically cracks the plastic.

It's also possible  that the float had a split in it from the beginning,
but I'm betting it was the water in the ethanol that caused the seeping
leak.

So - I replaced the plastic float with a brass float, and I don't use
ethanol anymore.
-- 
w swift ... on the road again.
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