> That should keep you quiet :-))

Not wrong there :-)  for a while at least

I have had the plunger out and there are no markings dots etc on it.
The only dot I could find is on the outer casing on the bottom of the
pump.

Also the plunger has a pin with a squared end that engages with just
one of the slots in the pinion body. this pin spins freely so
reassembly was quite tricky. Seems a bit odd as there are two slots in
the pinion body but only one engages with the plunger.

To get the rack and pinion out i would need to remove a second spring
clip deep in the body of the casing, so I haven't done that! I can see
that on reassembly it would be very easy to get the plunger on the way
around and logically that could cause the problems I currently have. I
have reassembled the pump with the plunger in 180 deg from where it
was and will see if that sorts things out.

thanks for all your help Peter those drawings were invaluable.

Matt