What SU stands for

[Andrew W. Macfadyen]

The later Chevettes had biger alternators after they encountered problems.

Mike Morrin wrote:

> At 08:40 8/07/98 +0100, Andrew W. Macfadyen wrote:
> >Lucas real weakness was alternator; the ACR series tended to have a 40k
> mile life
> >without a rebuild partly the fault of the car manufacturers who under
> sized the
> >unit to cut costs and tried to compensate by using a smaller pullley to
> spin the
> >alternator faster. . Main land european cars tended to use much  higher rated
> >units. Most UK cars used a 35ACR   a 35 amp  rated alternator where a
> German car
> >of the same size would use a 45 amp unit.
>
> Good story, but not true.  The 17, 20, 25 etc in Lucas model numbers does
> not refer to the current rating.  From a 1975 Lucas catalogue I get:
> 15ACR = 28 Amp
> 16ACR = 34 Amp
> 17ACR = 36 Amp
> 18ACR = 43 Amp
> 20ACR = 63 Amp or 66 Amp
> 23ACR = 55 Amp
> 25ACR = 65 Amp
>
> >Worst was the UK version of the Chevette
> >only  had a 25 amp alternator -- it would fail to   meet the demand by
> about 5 amps
> >with all the lights and heated rear window on.
>
> The Chevette had a 17ACR.
>
> The problems with the Lucase alternators were the brushgear which really
> did wear out at about 40k miles on some models, perhaps the brush springs
> were too strong and the rectifier assemblies on the smaller units which
> would fail due to vibration and the subsequent stress on the diode wires.
> regards,
>
> Mike Morrin