Usage:
Introduction
The front accessory drive provides up to five splined drives for accessories such as a charging generator, raw water pump, air compressor and hydraulic pump, in addition to the oil pump and water pump. An extension of the water pump shaft provides another convenient auxiliary drive.
Oil under pressure provides lubrication for shaft bearings and gears. An oil thrower and piston ring type seal prevent leakage between the crankshaft and accessory drive housing. Lubricating oil drains into the front scavenge sump.
Front Accessory Drive Housing
Removal and Installation
1. Remove any accessories that are attached to the front of the accessory drive housing.
PREPARING TO REMOVE THE ACCESSORY DRIVE COVER (D379 Engines Illustrated)
1-Bearing retainer and cover. 2-Fuel priming pump linkage. 3-Priming pump. 4-Covers (four). 5-Bearing retainer. 6-Crankshaft cover. 7-Accessory drive housing. 8-Bolts (two).
2. Remove the cover (6) and adapter on the end of the crankshaft. At assembly coat bolts (8) with 7M7456 Loctite Sealant and install with copper washers under their heads.
NOTE: On D399 and D398 Engines, remove the vibration damper and the adapter. See the topic, VIBRATION DAMPER.
3. Attach a suitable hoist to the accessory drive housing (7) and remove the bolts securing the housing to the plate and block.
4. Remove the housing as illustrated. Approximate weight 200 lbs. (90 kg.).
5. Inspect the baffle (10) and replace if worn or damaged. Nicks and burrs should be removed from the chamfered edge to prevent damage to the piston ring seal (9) during installation.
REMOVING THE ACCESSORY DRIVE COVER (D379 Engines Illustrated)
8-Thrower. 9-Piston ring seal. 10-Baffle.
6. To install the accessory drive housing, remove or loosen the bolts as required which mount components between the engine block and oil pan base.
7. Loosen the bolts holding the oil pan base to the engine. Raise the front of the engine approximately 3/8" in. (9,5 mm) and insert spacers between the engine and oil pan base.
8. Inspect the gaskets and replace if damaged.
9. Install the accessory drive housing.
NOTE: The leading edge of the baffle (10) is chamfered so that the piston ring seal (9) will compress in its groove and center in its bore during installation.
10. Remove the spacers from between the oil pan base and the engine block. Apply 7M7456 Loctite to bolt threads and tighten the bolts. Install and/or tighten bolts removed or loosened in Step 6 above.
Disassembly and Assembly
1. Remove the bolts and locks from water pump drive gear (1) and remove it from shaft.
2. Remove the retaining washer from the idler gear (7) and remove the gear from the stub shaft. Remove the stub shaft.
3. The oil pump drive gear (8) is splined to the oil pump drive shaft. Remove the gear.
4. Remove tube (4). Rotate the crankshaft to gain access to bolts securing the end of the tube.
ACCESSORY DRIVE GEARS (D379 Engines Illustrated)
1-Water pump drive gear. 2-Main idler gear. 3-Crankshaft gear. 4-Tube. 5-Thrower. 6, 7-Idler gears. 8-Oil pump drive gear. 9-Balancer gear. 10-Plate.
5. Remove the main idler gear (2) and its stub shaft by rotating the crankshaft to gain access to the bolts securing the stub shaft to the engine block and plate (10).
REMOVING THE MAIN IDLER GEAR (D379 Engines Illustrated)
6. Remove the idler gear (6) and the stub shaft as a unit. The crankshaft can be rotated to gain access to the bolts and locks securing the stub shaft to the plate.
NOTE: Remove retainers from gears (2) and (6) and inspect bearings and stub shafts. Replace bearings in gear (2), (6) and (7) if the maximum clearance is greater than the maximum permissible clearance given in the SPECIFICATIONS.
7. If it is necessary to remove or replace the thrower (5), see the topic, CRANKSHAFT.
NOTE: If plate (10) is removed, from later engines, check the plate position indication mark so the correct side of the plate is installed to the front. The front of the plate for SAE Standard Rotation engine (counterclockwise as viewed from the flywheel end) is marked "FRONT STD. ROT." The front of the plate for SAE Opposite Rotation engine (clockwise as viewed from the flywheel end) is marked "FRONT REV. ROT."
NOTE: Accessory drive gear trains are identical on these Engines except for balancer gear (9) used on the D379 Engines. On SAE Standard Rotation engines the balancer gear "B" timing mark must align with the "B" on the main idler gear (2) and the "C" on the main idler gear must align with the punch marked tooth (four, five or six punch marks) on crankshaft gear (3). On SAE Opposite Rotation engines, the balancer gear "R" timing mark must align with the "R" on the small idler gear and the other "R" on the small idler gear must align between the two marked teeth (with two punch marks) on the crankshaft gear. On D398 and D399 Engines, no timing of the accessory drive gears is necessary.
(SAE Standard Rotation Engine)
(SAE Opposite Rotation Engine) TIMING BALANCER GEAR ON G379 & D379 ENGINES
8. Assemble accessory drive components in reverse order of disassembly.
NOTE: At assembly install small gaskets under nuts for retaining right end of tube (4), and coat the sealing surfaces of idler gear (7) stub shaft, tube (4) and main idler gear (2) stub shaft with 7M7260 Liquid Gasket Material. Apply 7M7456 Loctite Sealant to the threads of mounting bolts for these components. Tighten the bolts to torque values as follows. 1/2" dia. bolts 85-95 lb. ft. (11,8-13,1 mkg), 5/16" dia. bolts 29-35 lb. ft. (4,0-4,8 mkg), 3/8" dia. bolts 36-44 lb. ft. (5,0-6,1 mkg).