As a Case owner, I will pass on the Case Road Locomotive question. Maybe Colin could answer that.:rant:
My comment has to do with the intercepting valve. While I realize this is "A-A only", I'm commenting on certain equipment.
I know of four cases of Reeves cross compounds that had terrible results due to the intercepting valve. Three of them were US engines and two had problems with countershaft bearings that pulled out of the back headsheet and wagon top of 32 hp Reeves cross compounds. It broke the studs or tore them out of the sheets and they were tapped into water or steam space. (that would sure ruin my day) The other engine was a 32 Reeves cross compound Canadian Special with an upper cannon bearing bolted into wing sheets, eliminating the problem of the above two engines. However this one broke the countershaft. I know of another 32 US cc that broke the countershaft, in lieu of tearing the bearings out of the headsheet and wagon top.
What happened is with a great load on the hitch, the engineer allowed the RPMs to drop too low on the motor, when opening the intercepting valve. With, in the neighborhood of, 150% of brake horsepower applied to the drive train, the master pinion on the crankshaft is trying to walk the intermediate gear right out of the gear train. It has a tremendous strain backward against the boiler. Something has to give and that is the area, at least on a Reeves, where it happens.
It is a remarkable valve, but needs to be respected. When an engineer knows he isn't going to make a hill or a tough spot, simple it early... Not late, or you are taking one heck of a chance with some prescious parts.
Gary
