With reference to the letter from P. H. Simon in January’s edition concerning alternator failures. He mentions replacing two alternators at £20 and £29 and having no joy from Joe Lucas due to his guarantee having expired. If his alternator fails again I would suggest that he takes it to any competent radio/television/electronics/electrical engineer who will remove the plastic end Cap and find that one of the nine silicon diodes cast into three heat sinks is either short circuit or open. circuit (probably the former). The cure is then to find a suitable diode—an easy matter for a capable engineer—attach some stout wire to it and bridge the offending diode after having snipped away the one connectiog lead—the other conductor is the heat sink itself. Stage two is to make sure the new diode is insulated from the rest of the alternator. That’s all there is to it! Total cost of parts—less than £1.
This is the cure effected to a friend’s Toledo some time ago as 3 temporary measure that looks like becoming permanent. As a rule it does seem that it is the rectifier as against the regulator that gives trouble in alternators.
Incidentally, I believe that the rectifier can be bought •as a whole from Lucas for about £9, but I may be wrong. I wonder who make the other £20?
As a point of interest alternator’s are acclaimed on the basis of supplying charge to a battery at low engine revs on the principle of increased excitation to the field winding to boost output volts—the same can be done on a dynamo with little redesign, but that’s another story.
I hope this letter is of use to someone in the future.
Bewdley, Worcs. P. C. HARDCASTLE