THE VALVE-GEAR. 75 



In placing the engine on its dead-centers, in examining 

 the valve setting, or in setting the valve, it should always be 

 turned in the direction indicated by the reverse lever, that is, 

 if the reverse lever is in the forward end of the quadrant, 

 the engine should be turned "under," or in the direction in 

 which it runs when threshing. If turned past the mark, it 

 should be turned the opposite way and again brought to the 

 mark, moving in the right direction. This eliminates any 

 error due to lost motion., 



To Determine if the Valve Setting has been Disturbed. 

 New engines have their valves set at the factory before being 

 painted, so that broken paint often reveals the fact that some- 

 one has re-set the valve. Besides this indication, "Case" 

 engines are provided with marks, by means of which, one 

 can determine whether or not the valve setting has been dis- 

 turbed since the engine left the factory and, if it has been 

 disturbed, furnish the means to bring it back to the original 

 setting without removing the steam chest cover. The eccen- 

 tric hub and the shaft are marked, as with a sharp cold 

 chisel, so that the marks meet when the eccentric is in its 

 proper position. When one suspects that the eccentric has 

 slipped from its original position, an examination of these 

 marks will show whether it has or has not. If it has slipped, 

 the trouble may be corrected by loosening the set-screws and 

 rotating it around the shaft until the marks correspond. 

 An eccentric is liable to slip when it becomes hot from run- 

 ning without oil and this tendency in such cases is sometimes 



