[dave-r]

I'd rather use a pin, like MSD does with the upper collar (the split-tube-like pin, I don't know how you call these in English). I'll look into this. I have an aluminum bar somewhere I bought when I needed to make spacers, there should be some left.

Split pin.

Only problem with that is lack of adjustment.

[dave-r]

My mate Trevor is making them now. In aluminium or stainless steel (your choice) and two grub screws in each one.

Email Trevor at mopar@tesco.net

Prices are;
Aluminium £8.50
Stainless £10.50

£1.00 from each sale will go to Little Havens childrens hospices.

[fbernard]

You've got a point about adjustability (or I would have to drill for the pin a bit too low on the shaft, and machine the collar until I have the desired clearance).

Since there's no relative movement between dist shaft and pump shaft, I might even be inclined to imagine a spring-loaded system, or a rubber insert between the collar and gear.

I need more alcohol to think this through!