I think that this conversion is a little more involved than what at first meets the eye.

From memory, the L series shaft is 1/2" [12.7mm] diameter, while the A series shaft is 12mm. If this is correct, then it means that the A series shaft can't be used in the finished product as it will be a loose fit in the rotor, unless some form of adaptor sleve is made.

If the L series shaft is used, the pump housing needs to have the bore enlarged to fit it, but I don't remember if the L series shaft is long enough without removing the lock pin & pushing the shaft up inside the rotor by a fair amount. I think that this is why this pump has a plug of silicone in the bottom of the rotor.

If all of the above is true, then another way out would be to make a custom stepped shaft. 1/2" at the bottom to hold the rotor & 12mm in the main shaft to fit the pump & the drive gear on the end.

Stirlingmac, can you clarify this for us?
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