I have prepared a drawing of the Pattern F386 D Valve on Climax CN 1551 (14.5" x 16"). Although the drawing is preliminary as the new operator at Cass shut down the MSR&LHA Climax restoration project (I have been unable to confirm the measurements with calipers), my preliminary measurements determined that the Exhaust Port in the D Valve was offset from the center of the D Valve.

John Lewis has provided a Climax drawing of Pattern F458 D Valve (15") which confirms the offset in Climax D Valves.

What I do not know is which side of the D Valve was the front. All the info I have is included as notes on the drawing. Any insight as to the orientation of the D Valve would be appreciated.

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I think I have figured out how Climax calculated the machining of the D Valve. Using the method I think was used, centering the Johnson Bar and centering the D Valve on the valve seat would automatically correctly place the D Valve Exhaust Port.

A drawing illustrating the method and assumptions is attached. Comments, corrections and thoughts are welcome. A few additional changes based upon the Climax drawing of Pattern F456 D Valve (15") were also made - The 15" D Valve has many similarities to the 14.5" used on CN 1551.

Thats the basic method I used to reset a valve on the 1910 climax I worked on when it slipped a valve right in the middle of a public road crossing. Luckily we had the right tools on board and were able to quickly open the steam chest up and center the valve and get the train moving again. We had called back for a crew to come out and retrieve us but were able to execute the repair hot and get moving again before they found another crew to come get us.

Some additional notes and details added to drawing.