ignition light (again)

DAV8

Member
Hi All, sorry about this, been here before, about 18 months ago the ignition light on my 1971 V8 auto started flickering, didn't seem to have any effect on the running of the car, I changed the 3AW unit but this made no difference, about 3 months ago the light ceased to flicker, travelled about 500 miles so I thought all is well, had a short run today and the light came on and stayed on!! oh dear I said (I think thats what I said) the amp needle well into the minus sector especially at idle as I would expect so, drove straight home and allowed the engine to cool, checked all the connections and all seem okay, started the engine and no red light? then carried out some checks with a multimeter, checked the battery with the engine stopped gives a reading of 12.75 (okay) run engine at idle gave a reading of around 14.40 (okay) amp needle well into plus sector, increased revs to about 2500 gave same reading, switched on all lights etc and then the red light came on, amp needle well into the minus sector and a reading on the multimeter of around 11.80/12.00 well too low!, stopped engine and carried out all the same tests again this time with no red light etc, amp needle well into the plus sector eventually settling down to a mid position. The alternator is a Lucas 11AC and has not had any work done on it for perhaps 30 years, should I suspect that this might fail altogether in the near future, or should I suspect the 4TR unit this being the original, has anybody else experianced anything similar, what are these replacement 4TR units like ? can anyone please help or advise.
Best Regards Dave
DAV8
 
Hi all, okay, done some more tests and I ended up with the warning light some times on and sometimes not? then with the engine idling and the warning light on I reached over and gave the 4TR unit a thump and the light went out!! so I am suspecting this is the fault, I bought a new 4TR unit from Holdens and this seems to have done the trick, although the new unit looks different from the original (viewing the underside) but nevertheless I have no warning light on. Hope this helps anyone with similar problems.
DAV8
Dave
 
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