PULLEY-CRANKSHAFT 6N5300 - Caterpillar

3512 Vehicular Engines Equipped With UG8L Governor And 2W2255 Cylinder Mounting GroupThe 2W2255 Cylinder Mounting Group has the parts which are needed to mount an OEM supplied double-acting air cylinder for control of engine rpm. With this group, a spring is used between the air cylinder and the governor shaft to dampen shock loads. The air cylinder should be adjusted so that there is a gap between the stop bolt and the spring when operating at low idle rpm. See the illustration. If there is no gap, the cylinder may put too much force on the idle stop lever in the governor and break the lever. If the idle stop lever breaks, it is possible for the engine to overspeed.
To correctly adjust the air cylinder and linkage, use the procedure which follows.
1. Remove or block the air supply to the cylinder.2. Set the low idle rpm on the governor to 75 rpm less than normal low idle rpm.3. Connect the air supply to the cylinder.4. Adjust the cylinder linkage so the engine runs at normal low idle rpm when the cylinder is completely retracted.5. Make sure the engine will go to high idle rpm with the cylinder extended.
Cylinder Mounting Group.