Q. How much “lead” should a valve have?
A. There is no general rule for the amount of lead that would be best suited for all makes of engines. It must be determined by the design or construction, speed and work required, to produce the best results for economy and quietness in running.
Q. What is a throttle engine?
A. A throttle engine is one in which the speed is controlled by throttling the steam with a governor, as opposed to an automatic engine in which the speed is regulated by varying the point of cut-off at the valve.
Q. What is the difference between a stroke and a revolution?
A. A stroke is the movement of the piston, from one end to the other of cylinder. A revolution takes two strokes of piston.
Q. How are steam packing rings put on the piston head?
A. Remove the back cylinder head and take the piston and rod out of the cylinder, and stand it “head up.” Then place the inside of the ring, opposite to the opening, against the side of the piston head next to you; gradually press the ring open with your hands, and it can be easily slipped over the head and put in place.
Q. How is a piston put into cylinder?