Fellow sworkers:
I have been fighting an electrical gremlin in my TR for the past several
days.
At first I thought there was a problem with the starter (thanks to all who
offered
advice) but now I realize the problem was that the battery was not getting
charged
and there was not enough current available to spin the starter motor. As an
aside,
while checking out the starter I found the top bolt had loosened considerably
and
the whole assembly was flopping about. I thought that was the cause of my
intermittant starter problem, but not quite. After putting a voltmeter
across the battery and trying to start the car, it was obvious the problem
was simply a flat
battery. A check with the hydrometer confirmed this, all cells being equally
low.
How can that be I thought. The ammeter shows considerable discharge while
cranking the starter, then after the car starts, slowly wends its way back to
zero,
making me think the battery was being recharged. So a digital voltmeter
across the battery after a thorough off-line charge shows 12.6 volts at rest,
falls down a coupla volts during the start operation, then goes back to 12.6
or so. Putting the same
DVM from ground to the D terminal on the E reg. shows 14.5 (about what I
would
expect). The charge current (according to my schematic) goes from one of the
A
terminals through the ammeter thence to the batter +ive term. This is where
I need
some help. Shouldn't the voltage across the battery be in the 13.8-14.2
range just
after starting? The ammeter shows current flow but the voltmeter shows
quiescent battery voltage, and even I know you cannot charge a battery unless
the E applied
is greater than 12V. Do these lovely Lucas ammeters have a shunt just for
this purpose and maybe mine is open circuited?
As usual, any and all info is appreciated.
Replies to foxb@macom.com will get read before those to AOL, FWIW.
Cheers,
Barry W. Fox 65 TR4A CT51681L
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