Frank "Swamp Yankee" Krajewski wrote:
> Several have suggested that pump polarity is irrelevant since
> it is not a factor cinsidered when changing a car from + to -
> ground.
Barney, Dan, and others (who are far more knowledgeable 'bout how
the smoke moves around in electrical bits) have confirmed what I
suspected ... the coil in da pump isn't sensitive to polarity.
However, when they began to replace the condensor with various bits
(polarized capacitor, then diode) in an attempt to prevent the
pitting of the points (caused by the spike that comes from the
collapse of the magnetic field in the coil when the points open),
the pumps became sensitive to polarity. The fitting of a diode
(in lieu of the condensor or capacitor) is the preffered method
for protecting the points. So, when changing a car from + to -
ground, pump polarity could should be considered ... the polarity
of the pump is determined/changed by removing the 'bakelite'
cover and examining/swaping the orientation of the diode.
> This is an interesting point. It makes me wonder why there is a
> significant increase in the price of + ground fuel pumps from most
> vendors if it makes no difference. Anyone know?
They like to make money? ... ;^)
Safety Fast! ... larry.g.unger@lmco.com
'61 MGA 1600 MkII
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