On one of the latest jobs, a very sweet W111 220SE cabriolet i had to sort out a leak in the power steering. Specs call for a maximum of 1 mm free play in the shaft ,but this was had close to 10 mm and a slight leak . After contacting the local vickers dealers and getting no where fast I bought the complete kit to overhaul the pump from Mercedes Classic Center. Special tools are required to reassemble the pump ,mainly to fit the bush into the housing after the shaft and the two shell half’s are fitted, then a further tool to fit the outer seal.
The above pic shows the bush installer in place
The original shaft has a straht shaft where the pulley fits but the new one has a taper with a slot for a woodruff key.
A new pulley was also installed with a taper bore ,thankfully available from the classic center.