All the parts for the pump head on my Monotype Composition caster are now clean and mostly shiny. There are two cotter (split) pins which I did not bother cleaning since I plan on replacing them.
The lower crosshead 19H1, which I could not extract from its compartment, is still filthy. It looks like I might have to try to clean it in situ, as a test insertion of the Piston Operating Rod 19H would get stuck on grunge after going in about an inch. Furthermore, this part has oil passages in it which I should clear out as well. I can’t use the paint remover on this part because there would be no way to rinse it off properly, so I will have to use something that can just be wiped off.
I have already begun a bit of reassembly: The Pump Body Spring Rod 31H1 and its crosshead 31H2 have been reassembled and the nut 31H10 installed and tightened. This turned out to be a press fit loose enough that a rubber mallet could be used to drive the parts together. I made a quick try at re-installing this rod along with its spring and sleeve, but it has to run through a second hole in the lower crosshead 19H1, which also acts as the lower land for the spring, and I found that the pressure from the spring made it next to impossible to get the end of the rod inserted into the hold in the crosshead. Perhaps I could arrange something to keep the spring compressed during installation, or perhaps having the Piston Operating Rod 19H in position would stabilize the crosshead enough to enable insertion of the Pump Body Spring Rod.
(for a part code reference see the photo of the parts right after disassembly)
Once I have both crossheads (31H2 and a19H3) installed on their rods I will repaint the unmachined surfaces of these parts. Then I will do the reassembly in earnest of everything except the pump spring group 20H, for which I have to make modified parts to accommodate the pump latch mechanism, which was the goal that started this entire exercise.
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