I have an erratic problem with starting my '85 Westy.  Sometimes she will
start and run fine, other times she just cranks and cranks until I give up
and take my wife's car.  The problem seems to be that I am not getting a
spark from the coil (checked by pulling center wire and observing no spark
across small gap), but the coil itself works fine in my friends '85, so I am
pretty much at a loss...

I guess I need to know where to start looking, maybe a bad hall sender?
Please help, camping season is almost here.

Thanks in advance.
Jay Brown
'85 Westfalia
'72 Riviera