Usage:
The raw water pump is mounted on the lower left front corner of the front accessory drive housing (13). The pump shaft (12) and bearings (11) and (14) receive their lubricant by way of passages (4) and (6). End thrust is taken by the thrust bearing (5) which also receives its lubricant through passage (4). An oil seal (10) prevents the loss of lubricant from the lubricating system.
The water seal (2) and water thrower (9) prevent any water from entering the lubricating system. Later shafts have a machined thrower to replace the earlier type pressed on thrower. A hole in the bottom of the pump housing (3) allows for the escape of any water which bypasses the water seal.
1 Impeller.
2 Water seal.
3 Pump housing.
4 Oil passage.
5 Thrust bearing.
6 Oil passage.
7 Inlet elbow.
8 Gaskets.
9 Water thrower.
10 Oil seal.
11 Bearing.
12 Shaft.
13 Front accessory drive housing.
14 Bearing.
CROSS SECTION OR RAW WATER PUMP
Gaskets (8) between the inlet elbow (7) and pump housing (3) are used to adjust the impeller end clearance.
Removal And Installation
1. Drain the raw water system by removing the plug (6).
2. Disconnect the raw water inlet line from the elbow (2).
NOTE: The bearing retainer (5) should be removed to inspect the pump shaft bearing which is pressed into the retainer. Replace the bearing if necessary.
PREPARING TO REMOVE RAW WATER PUMP (D399 Engine Illustrated)
1-Elbow. 2-Elbow. 3-Raw water pump. 4-Bolts (six). 5-Bearing retainer. 6-Plug.
3. Attach a suitable hoist and remove the bolts (4) which secure the raw water pump (3) to the front accessory drive housing.
4. Remove the raw water pump assembly as shown. Approximate weight 144 lbs. (65,3 kg).
REMOVING RAW WATER PUMP ASSEMBLY (D398 Engine Illustrated)
Disassembly And Assembly
NOTE: Outlet elbow (1) and primer tank (4) can be removed as a unit but it is necessary to first remove the bolt (2) which extends through the primer tank into the pump housing (6). The primer plug (3) can be removed to fill the primer tank after the unit is assembled and installed.
PREPARING TO DISASSEMBLE RAW WATER PUMP (D399 Engine Illustrated)
1-Outlet elbow. 2-Bolt. 3-Primer plug. 4-Primer tank. 5-Inlet elbow. 6-Pump housing.
REMOVING INLET ELBOW
6-Pump housing. 7-O-ring seal. 8-Inlet elbow and cover.
REMOVING IMPELLER
9-Impeller. 10-Centering spacer. 11-Puller. 12-Bolt.
1. Remove the inlet elbow and cover (8) from pump housing (6) and inspect O-ring seal (7).
2. Insert two 5/16" NC bolts (12) 2" long into the holes provided in the impeller (9).
3. Remove the impeller with the aid of an 8H700 Puller (11) and T774 Centering Spacer (10).
DISASSEMBLING IMPELLER
9-Impeller. 13-Locks. 14-Plate assembly. 15-Gasket.
NOTE: Install gasket (15) against impeller and notches on plate assembly (14) engaged with locks (13). Lift the the impeller (9) into the pump housing so the parts remain in place. Install the retaining washers and nut on the shaft.
REMOVING SHAFT ASSEMBLY
6-Pump housing. 16-Bolt. 17-Thrust bearing. 18-Bearing retainer.
4. Remove the bolts (16) securing the thrust bearing (17) and bearing retainer (18) to the pump housing (6). Remove the shaft.
NOTE: The bearing and oil seal can be removed from the bearing retainer (18) if replacement is necessary. The oil seal should be installed with the lip facing the gear (19).
DISASSEMBLING SHAFT ASSEMBLY
17-Thrust bearing. 18-Bearing retainer. 19-Gear. 20-Water thrower (some earlier pumps).
5. Upon assembly check the impeller end clearance using a thickness gauge (21) inserted between the impeller and inlet elbow (8) as illustrated.
6. Use the necessary amount of gaskets (22) to obtain the correct impeller face clearance of .005-.020 in. (0,13-0,50 mm).
7. Tighten impeller nut to torque of 55 lb. ft. (7,6 mkg).
CHECKING IMPELLER END CLEARANCE
8-Inlet elbow and cover. 21-Thickness gauge. 22-Gaskets.
Water Seal Replacement
Water leaking from the drain hole in the bottom of the pump indicates that the water seal should be replaced. The seal may be replaced with the pump either installed or removed from the engine.
1. Remove the water pump inlet elbow and impeller (1) as previously described.
2. Remove the retaining pins from dowel pins (2).
3. Inspect and replace any worn or damaged parts.
4. Use new retaining pins upon assembly.
PREPARING TO REMOVE WATER SEAL
1-Impeller. 2-Dowel pins.
REMOVING WATER SEAL
3-Retainer ring. 4-Bellows assembly. 5-Plate.
5. Check the impeller end clearance. See the previous topic.