Commander water pump overhaul


Water Pump Overhaul.
1. Remove grease seal from drive end
2. Remove circlip from behind oil seal.
3. Knock the pump shaft out (i.e. away from engine) with a small drift , this will break the pump seal in half.(It isn’t possible to strip the pump without destroying the seal)
4. Remove the outer bearing retaining circlip and remove both bearings inner bearing inwards, outer bearing out.
5. Clean the bore.
6. Fit the new inner bearing to the drive end of the pump
7. Fit the new outer bearing to the shaft (Only possible from the drive end). Fit the small circlip up against the outer bearing on the shaft. 8. Fit the small circlip in the other slot on the pump shaft.
9. Carefully fit the assembled shaft into the pump body. Warming the casting may help. Make sure the shaft locates in the drive side bearing.
10. Check the drive end of the pump shaft is flush with the inner bearing.
11. Fit circlip to retain outer bearing. 12. Fit the pump seal by alternately using a drift which will just fit over the pump shaft and a second drift which rests on the outer brass coloured lip . 
A smear of wellseal on the shaft and Silicon sealant on the housing will help.Maintain the distance between the inner and outer parts of the seal. Drifting the seal in by hitting the centre only will compress the seal too much and break the ceramic ring which acts as a water barrier. Refit impeller making sure it clears the pump body.

Checking the oldham coupling clearance:
Screw the drive into the eccentric shaft but do not tighten it. Fit the oldham coupling, retaining it with thick grease. Refit the water pump. Screw the impeller anti clockwise thus screwing the oldham coupling out of the end of the eccentric shaft towards the water pump. When the clearance is correct it should be possible to turn the impeller one quarter turn. Graham.