ROD 4T2500 - Caterpillar

Remove and disconnect items in the V of the engine that obstruct removal of the governor drive housing.Lift the complete assembly from the V of the engine. A 3/8" NC forged eyebolt may be installed at the rear of the governor drive housing to aid in removal of the unit.As the housing is lifted off, the vertical oil supply tube from the main oil manifold to the governor drive oil manifold may remain in the main oil manifold. Inspect the top and bottom seals on this tube before installation of the housings.Install in reverse order of removal.Replace gaskets and seals as necessary. Apply 7M7260 Liquid Gasket Material to the cylinder block and mating surfaces of housings.Disassembly And Assembly
Governor Drive and Tachometer Drive
REMOVAL OF TACHOMETER DRIVE
1-Tachometer drive adapter. 2-Drive shaft. 3-Thrust washer. 4-Drive gear. 5-Drive housing.Remove tachometer drive adapter (1) and housing (5) as a unit. When housing (5) is removed from adapter (1) shaft (2) can be removed.Use a 5/8 in. (15,8 mm) diameter driver to drive gear from thrust washer. At assembly, heat the thrust washer to 250° F. (120° C.) and push the washer on gear until flush with top of gear. There should be .015-.045 in. (0,38-1,14 mm) end clearance.Install a new bearing in the housing if necessary.
REMOVING TACHOMETER DRIVE GEAR
3-Thrust washer. 4-Drive gear.
GOVERNOR DRIVE
6-Retaining bolts and locks (six each). 7-Governor drive pinion assembly. 8-Bolts. 9-Governor drive housing.The governor drive pinion assembly (7) can be removed for parts inspection with the governor drive housing (9) in place. If parts are replaced, the backlash between the pinion and bevel gear must be adjusted. Backlash between the pinion and drive gear is adjusted with shims under the governor drive shaft thrust plate.
REMOVING DRIVE SHAFT
10-Locknut. 11-Gear. 12-Bolts. 13-Shaft drive gear. 14-Thrust plate. 15-Drive shaft. 16-Gear.Remove shaft drive gear (13) by turning the puller bolt assembly counterclockwise. This forces a collar on the bolt against the plate on the gear hub, thus pulling the gear. At assembly tighten bolt assembly, after timing, to torque of 265 35 lb. ft. (36,6 4,8 mkg).Inspect and install new parts if necessary. SAE Standard and SAE Opposite rotation engine use different drive gear (11) and pinion. For proper drive shaft adjustment, see the topic ADJUSTMENT.Adjustment
To check the backlash between the pinion and bevel gear, set up a dial indicator by use of parts from the 8S2328 Dial Test Indicator Group, as shown in the illustration.Adjust the backlash to .002-.006 in. (0,05-0,15 mm) by removing or adding shims (2) behind thrust plate (1).
CHECKING BACKLASH
1-Thrust plate. 2-Shims.