I'm embarrassed to continue to take up everyone's time with this problem.
However since I've gotten so many helpful suggestions, both on and off list, I
feel I owe an update.
(Note: Because the original white wire running under the car and back to the
fuel pump is suspect I used a jumper from the switched #3 lead on the fuse
block [that's the lower inboard lead] from which the white wires are fed to
power the fuel pump and run load tests.)
To summarize the situation:
1. When I turn the ignition key on the (NAPA) fuel pump energizes and pumps
fuel till the bowls are apparently full, then goes into it's "idling mode",
clicking less frequently and more faintly (much like and SU only a bit louder).
2. As soon as I start the engine the fuel pump stops clicking and pumping,
and within a minute the engine dies.
3. If I shut the key switch off and then turn it on again, the same process
begins: The pump energizes, etc., only to shut off again on restart.
4. When I clip the jumper running to the fuel pump onto either the battery
or the unswitched lead (#1) at the fuse block the pump starts to pump, AND
CONTINUES TO PUMP EVEN AFTER THE ENGINE STARTS! No pump shutdown, no running
out
of fuel, no problem.
Several folks suggested that the problem might be in the alternator and told
me to disconnect it and see what happens. With the pump energized off the
switched terminal I completely disconnected all wires to the alternator and
started the engine with the same result: The pump stops and the engine
eventually
runs out of fuel and dies. Absolutely no effect on steps 1-4 whether or not
the alternator is hooked up.
But here's something interesting: In doing voltage tests at the #3 post and
the battery I found that there is about 12.5 volts before starting, that the
voltage drops to perhaps 10.5 during cranking and that as soon as the engine
fires over the voltage climbs to about 18 volts. That's too high and I am
taking the alternator to the repair shop tomorrow. It doesn't explain the
problem
to me but it is something that I need to put right before continuing.
I have not yet investigated the quality of connections at the key switch
which feeds the switched side of the fuse block, though why the heater fan and
turn signals on the fused side of that switched circuit continue to work while
the fuel pump drops out is baffling.
But perhaps I'll find something there--tomorrow.
Thanks everyone for your patience.
Best--Michael Oritt
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