24. Q. If, with the automatic brake valve handle in running position, the brake pipe and main reservoir do not stand twenty pounds apart, where would you look for the trouble?
A. Would first learn if the maximum pressure head was properly adjusted, and if it were, would then look for the trouble in the adjustment of the regulating spring in the excess pressure head.
25. Q. What should be done?
A. The regulating spring should be properly adjusted.
26. Q. How should the adjustment of the regulating spring in either pressure head be made?
A. By removing the cap nut 25 or 17 and screwing the regulating nut 26 or 18 up or down as may be required.
DEFECTS OF THE GOVERNOR
27. Q. What would be the effect if one or both of the pin valves leaked?
A. Would cause a delay in opening of the steam valve after the pin valve had seated; and if air leaks by faster than it can escape through the relief port "c", pressure will accumulate in chamber "b" and force the governor piston downward, so as to partially or wholly close the steam valve 5.
28. Q. How can you tell if the pin valves leak?