FIXING A LOOSE ROTOR ARM

Some time ago, after fitting a new rotor arm, I noticed it was very loose on the distributor spindle - a temporary solution was to put some masking tape over the spindle, and press the rotor arm onto this - it works for a while, but does not last very long before it needs doing again.

My permanent solution to this problem now is as follows: - drill and tap the diameter of the rotor arm to take a 6BA screw, which can then be tightened against the distributor spindle carefully until all looseness is eliminated. I cut my screw down to the length that would just allow a spring washer to be fitted under the head to prevent it from coming loose, this also ensures that the screw will not foul on the condenser as the rotor arm rotates.

The second piece of advice is to pack the dynamo/distributor gears with grease, something I was not aware of. An easy job I thought - tin of multi-purpose HMP grease, out with the wire circlip and remove the end cap. Not so easy; it is concave, like a cylinder block core plug, a very tight fit and no places to lever or prise it out. A very strong magnet would not pull it out so I decided to drill a small hole through the centre of the cap and start a self-tapping screw in it, which enabled me to pull the cap out.

Before replacing the cap, I fitted a 4BA countersunk screw through the hole from the inside of the cap, which misses the dynamo end nut OK and also fitted a fibre washer and plain washer under the nut to form a grease seal. Now, when I come to do this job again, the protruding screw will ensure that I can pull the end cap out easily.

Shane Burrows – Solent A7C with many thanks