Dardal has given the best advice yet.
Also a few simple checks are as follows (but this is from
memory i haven't seen or owned a car with points for
15 years:-
1, With the dizzy cap off and the points closed switch
the ign switch on (run position) and open the points with
a plastic biro or similar you should see a small spark as
the points open.
2, Pull the king lead out of the centre of the dizzy cap
place it close to an earth (ground) ie engine block or
head, hold the lead with a thick glove or dry cloth to
prevent getting a shock, and flick the points again
you should see a spark jump to earth.
3, To check that the rotor arm has not failed do the
same as 2, but hold the free end of the king lead over
the contact in the upper centre of the rotor arm
(dont forget the thick glove) this time you should
not get a spark, if you do the rotor arm is bad.
Neil thorpe black 82 imp
www.imperial82.pwp.blueyonder.co.uk