FH - oil pump

Over three years ago now I pulled this sludgy oil pump out of the timing case, planning to look at it and consider it for further use. It would barely turn.

Since then, much has come and gone (some of it twice) but I have stripped the pump and freed the high spots in the drive that caused the seizure. With these Mazak/Zamak castings, impurities in the alloy corrode and cause the casting to swell and crack, in this case causing high spots in the drive gear bore and damage to the circlip recess - though fortunately nothing irreparable. 

The body casting had a bit of carbon in the smaller bores:

The ultrasonic bath fixed that, and revealed some scoring. If this leads to excessive wet-sumping we will have to replace the pump.

With it all back together and working, I realised there was a thrust washer missing, which is supposed to fit under the circlip. I'll have to make one.