There's not much going on here, so I thought I'd describe my afternoon's frustrations.
One of my jobs at the moment is overhauling the fuel injection pumps on a Crossley HR4. This is a 4-cyl 2-stroke 'scavenge pump' direct reversing diesel, from memory 285 bhp @ 300 rpm, built 1948. It's something like 10.5" bore by 15" stroke. The scavenge pump is a big single cylinder piston pump in line with the four power cylinders.
It's in a vessel which had been idle for 10 years, I helped to get it going again about 5 years ago. Part of getting it going involved freeing up the badly rusted injection pump.
We've finally got around to doing something a bit better with the pump, so I've tracked down some new control valves and excellent used main pump plungers and bores. These pumps are a bit different from the usual CAV/Bosch or Simms in-line pump, which use a plunger with a helical groove to control the amount of fuel delivered per stroke. These Crossley pumps have a simple pumping element whch connects to the control valve, which controls the fuel delivery. The pump plungers are 3/4" dia., the control valves 3/8 dia. The various bores are lightly pressed into a chunky cast steel (guessing) block, with copper sealing washers. I unpacked the control valves & checked they were OK. They're like the usual fuel pump elements in that they rely on a very close fit to keep the fuel in. I tapped out the old ones, cleaned everything & blew out the block thoroughly, before tapping in the new bores. Then came to fit the control valve plungers into their bores, disaster - two of them wouldn't fit (without persuasion).
To cut a long story short, I tapped these out two bores out of the block again and measured the OD's at the critical points & compared them with the old ones. The worst of the new ones was about 8 tenths of a thou bigger than the one it replaced on the OD. I put it in the lathe and polished, carefully, a similar amount from the body of the new valve bore. Refitted it to the block, hey presto, all is well, the plungers fit as they should
Tomorrows job is to refit to the engine and see if I can make it go again. Both this vessel and the 'day job' at the dry-dock are being taken by their respective owners to a commemorative bash for their builders (Yarwoods of Northwich) next weekend, so no rest for the wicked for a few days!
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service