[Steam-engine] Wachs Knock

Francis Orr steam.boat at verizon.net
Mon Oct 1 21:56:42 PDT 2007


Rick, 

Jim Mackessy's remarks reminded me of a 4 X 4 Upton marine engine we had in a boat in the 60s. It had a knock that sounded like a sledge hammer. After a complete rebuild, it quieted down but eventually came back. To make a short story out of it, we found the knock was coming from the connecting rod sliding left and right on the wrist. Further examination showed the cause of this was that the top of the cast column (cast on one side, steel on the other) had been broken at one time and welded back together. Therefore the piston rod and the connecting rod were not in alignment. Machining the top of the cast column and redoing the wristpin brasses fixed the knock. 

Francis A. Orr



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