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Monday 25 July 2011

Loco Maintenance

Fitting the remachined injector steam valve on Cochrane

The next few shots show measuring the slide valve lead on HL No.2, prior to reshimming
Peter demonstrating use of a trammel to determine piston front dead centre
The fixed valve face is vertical (part seen picture centre).
The horizontal valve rod pushes the slide valve across the face.
The valve itself is the right of the shot (flat against the face).
The 'lead' is the (dark) vertical gap between the face and valve.
'Lead' admits steam as the piston reaches the end of its stroke;
this steam is compressed and reduces knock in the motion.
Peter using feelers and a vernier to measure the lead
at front dead centre in the left hand valve.

Chris doing similar.
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