I had originally intended to install a new pump that I had acquired from a friend. However, further investigation
led me to be suspicious of the quality of new pumps and so I ended up rebuilding my original.
It all started when I noticed that there was about 1/16 inch play on the old water pump shaft (without brass housing)
when installed in the bushing deep in the block (beneath the jackshaft). This seemed a bit excessive
so I ordered a new bushing (145022) and wondered how I was going to get the old one out! Then I tried the new bushing
on the new shaft and there seemed to be a similar amount of play, even when gripped in a vice so the gap
in the bushing closed up.
In view of this, I consulted some senior opinion from the SOC and others, who confirmed that the quality of some new pumps had caused jack-shaft problems for some people, so they recommended rebuilding on the original water-pump shaft, if possible. Also, it seemed that a reasonable amount of play in the bushing was normal & desirable, to avoid any unnecessary strain on the jack-shaft.
So I decided to strip the bearing & oil-seal etc from the new pump, including the 6-vane impellor to replace the 12-vane that had been fitted in 1982. Disassembly of the new pump revealed much shallower knurling than on the old shaft:
The other noticeable difference was that the depth of machining of the gears on the old shaft was deeper than on the new:
The old shaft also had markings: ND3 ZEPHYR which were absent on the new one.
If anyone wants more detailed info about the make of new pump etc, contact me by email.
