en spring, or the packing rings of separate
exhaust valve leaking.

14. Q. What can be done if the engine will not operate compound when the
air pressure on the separate exhaust valve is released by the three-way
cock?

A. The separate exhaust valve has failed to close. Try jarring it with a
hammer on the front side, near the exhaust valve. With a bad case, take
the valve out, clean it and replace, if not broken.

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