103.  Q. When should lost motion between engine and tender be taken up?

A. When the lost motion becomes so great as to endanger the breaking of connections.

104.  Q. How do you proceed to pack a driving box equipped with a grease cellar?

A. Remove the filling plate on the inside of the cellar.  Pull down the indicators and follower plates, insert the grease between the follower plate and perforated plate; when full, replace the filling plate on the inside of the cellar and allow the spring and follower plate to force the grease through the perforated plate to the journal.

105.  Q. Please explain the principle on which an injector works.

A. With a lifting injector the steam valve is opened a small amount to furnish steam for the priming or starting jet.  This forces the air in the body of the injector and top end of suction pipe out through the overflow valve, producing a partial vacuum in the body of the injector.  Atmospheric pressure in the tank then forces the water into the injector body.  When it begins to come out through the overflow, a further movement of the steam valve opens the forcing valve wide, so a full supply of steam strikes the water at a high velocity and at the same time condensing.  This action of the steam gives the water sufficient velocity to overcome the boiler pressure and pass into the boiler.

106.  Q. Explain the passage of steam from the boiler to the steam heat pipe.

A. Steam is admitted to the steam heat pipe, in which there is placed a reducing valve through which it passes at reduced pressure, into the steam heat pipe under the entire length of the train.  The reducing valve is located in the cab close to the steam heat throttle.

107.  Q. If the steam heat gauge shows proper pressure, but the steam heat pipe pressure appears to be low, what should be done?

A. If the steam heat gauge is showing the correct pressure, there is an obstruction in the pipe somewhere, most likely in the steam heat hose, and this should be looked for and remedied; if the gauge is correct, then it is the reducing valve that is at fault and this should be readjusted, as well as the gauge.

108.  Q. What is the cause of failure with the second injector, and what should be done to obviate this failure?

A. Lack of attention and failure to use every day will allow joints to work loose and boiler check to fill up with mud and scale.  It should be tested every day and worked regularly so as to keep it in good working order.

109.  Q. If an injector stops working while on the road, what should you do?