15.  Q. If the engine stands with high-pressure side on the dead center and will not move when given steam, where is the trouble, and what may be done to start the engine?  Why?

A. The intercepting valve is stuck in compound position, so live steam cannot get to the low-pressure cylinder.  In a case of this kind, close the throttle, open cylinder and port cocks; when all pressure is relieved, use a bar to move forward the rod that works through the oil dash-pot, thus moving the valve to simple position and steam will pass to the low-pressure cylinder as soon as throttle is open.  The engine will not start, because with the low-pressure piston on the quarter, steam must be admitted to its cylinder to start the engine.

16.  Q. In the event of a breakdown, how should one disconnect?

A. The same as a simple engine with separate exhaust valve open, so engine will work simple instead of compound.

17.  Q. What may be done to shut off steam pressure from the steam chest and low-pressure cylinder?

A. To shut off steam from the low-pressure chest, pull out the rod that runs through the dash-pot as far as possible and fasten it in this position.  Then open the separate exhaust valve.

18.  Q. Is it important that air be pumped up on a two-cylinder compound before the engine is moved?  Why?

A. Yes.  Because the separate exhaust valve is opened by air pressure and the engine cannot be simpled without sufficient pressure.

19.  Q. How are the blows in a compound located?

A. The same as in a simple engine with the exception that any blow on the high-pressure side will not be heard when the separate exhaust valve is closed.  A blow on the high-pressure side will increase the pressure in the low-pressure side, so relief valves will pop on low-pressure side when working compound with full throttle.

20.  Q. What should be done if high-pressure piston of a cross compound is broken off the rod, or if the high-pressure or low-pressure cylinder head is broken?

A. Cover the ports on that side, open separate exhaust valve and run in; use live steam in low-pressure cylinder only, for the broken piston.  With broken cylinder head, would cover ports on that side.  Open separate exhaust and run in with low-pressure side.  Would not take down main rod, but would take out pop valves in both cylinder heads and see that the cylinder is properly oiled.  For low-pressure head broken, would cover ports on that side, open separate exhaust valve and use high-pressure side; need not take down main rod, but would see that the cylinder is well oiled.

21.  Q. In the event of separate exhaust valves failing to work when throttle is wide open, what can be done to assist in opening?

A. Ease throttle off very fine to reduce the receiver pressure; in a moment or two the separate exhaust valve should then move.  If this did not work, would shut off entirely, even at the risk of stalling, as in that event the train could be started again with engine cut in simple.