Skip to main content

SERIES 60 WATER PUMP (FRONT MOUNTED) (FM)

The centrifugal-type water pump circulates the engine coolant through the cylinder block, cylinder head, radiator and the oil cooler. See Figure 20486 . ‪

The pump is mounted on the front of the engine gear case cover on units built prior to 6R037024 and is driven by the water pump drive gear. The water pump drive gear meshes with the bull gear. ‪

Front Mounted Water Pump

An impeller is pressed on one end of the stainless steel drive shaft. The other end of this shaft has internal threads, and a retaining bolt secures the water pump drive gear to the shaft. Two identical roller bearing assemblies are used to carry the shaft See Figure 20487 . ‪

1. Locknut ‪

12. Drive Shaft ‪

2. Gear, Water Pump Drive ‪

13. Water Seal ‪

3. Snap Ring ‪

14. Impeller ‪

4. Bearing Race ‪

15. Seal Ring, Water Pump Cover ‪

5. Roller Bearing, Larger ‪

16. Bolt, Cover-to-housing ‪

6. Spacer Rings (2) ‪

17. Water Pump Cover ‪

7. Roller Bearing, Small ‪

18. Bolt, Pump Housing to Gear Case Cover ‪

8. Bearing Race ‪

19. Woodruff Key ‪

9. Oil Seal ‪

20. Small Pipe Plug, Water Pump Housing ‪

10. Seal Ring, Water Pump Housing ‪

21. Large Pipe Plug, Water Pump Housing ‪

11. Housing, Water Pump ‪

22. Drain Cock ‪

Front Mounted Water Pump Details and Relative Location of Parts

A rectangular rubber ring, located in a groove in the water pump housing, seals the water pump to the gear case cover. A smaller rectangular rubber ring, located in a groove in the water pump cover, seals the cover to the water pump housing. Engines built before October, 1989, are equipped with rubber O-ring seals on the water pump housing and cover. See Figure 20487 . ‪

An oil seal is located behind the bearing assemblies, and a unitized, spring-loaded, face-type water seal is used behind the impeller. This seal prevents water from leaking down the shaft and into the gear case. It also prevents lubricating oil from entering the cooling system. The water and oil seals cannot be replaced without removing the water pump from the engine. ‪

The pump bearings are lubricated by splash oil through a passage from the front of the pump housing. ‪

Repair or Replacement of Water Pump (FM)

To determine if repair or replacement of the water pump is necessary, perform the following procedure. See Figure 21997 . ‪

Flowchart for Repair or Replacement of Water Pump (FM)

Draining and Removal of Front Mounted Water Pump

Drain the cooling system as follows: ‪

Open the drain cocks located at the right rear corner of the engine, at the bottom of the water pump and in the bottom of the thermostat housing. ‪

Remove the water pump as follows: ‪

  1. Loosen the hose clamps and remove the coolant hoses from the water pump housing.
  2. Loosen and remove the three water pump housing-to-gear case bolts. Remove the water pump from the engine by pulling it straight out of the gear case.

Disassembly of Front Mounted Water Pump

Disassemble the water pump as follows: ‪

  1. Loosen and remove the two water pump cover-to-pump housing bolts. Remove the water pump cover by pulling it straight out of the water pump housing, to prevent possible damage to the seal ring.

    NOTICE:

    If a vise is used to secure the water pump drive gear for locknut or impeller removal, use soft jaws on the vise and exercise extreme caution to prevent damage to the water pump drive gear teeth. ‪

  2. Clamp the water pump drive gear in a vise, with the impeller facing up. Use a two-screw puller and remove the water pump impeller from the shaft, using the two threaded holes in the face of the impeller.
  3. Place the water pump face down on a press bed. Using J 35988-5 , part of tool set J 35988-D , and two breaker bars, loosen the locknut that secures the water pump drive gear to the shaft. Remove the locknut. See Figure 20489 .

    Water Pump Drive Gear Locknut Removal (FM)

  4. Use a two-jaw puller to remove the water pump drive gear from the drive shaft.

    Note: Use care not to lose the Woodruff key.

    EYE INJURY

    To avoid injury from flying parts when working with components under spring tension, wear adequate eye protection (face shield or safety goggles).

  5. Remove the snap ring from the water pump housing. See Figure 20490 .

    Snap Ring Removal (FM)

  6. Support the water pump housing, engine side down, using steel blocks or plates, to allow at least 76 mm (3 in.) of clearance between the pump housing and the press bed.
  7. Press the drive shaft and bearings assembly out through the back (engine side) of the water pump housing, until both bearing races are clear of the housing.

    NOTICE:

    Use care not to damage the housing. Damaged housing bore will cause coolant leaks and damage to the engine. ‪

  8. Remove both the water and oil seals from the housing using a brass drift and hammer.
  9. Support the drive shaft assembly on two steel blocks, at the bearing inner race. See Figure 20491 .

    Removing Bearing Assemblies (FM)

  10. Press the drive shaft out until it is clear of both bearing and race assemblies. Discard the used bearings, races and the two spacer rings located between the bearing packs.
Inspection of Front Mounted Water Pump

Inspect the water pump parts as follows: ‪

  1. Visually inspect the parts for cracks, wear or other damage.
    1. If parts are cracked, worn or have other damage, replace damaged or worn parts. Refer to section .
    2. If parts are not cracked, worn or damaged, reuse remaining components.
  2. Inspect the water pump housing for relief slots in the water seal cavity. If pump is without the relief slots, modify the area in which the impeller rides to add the slots. See Figure 20492 .

    Note: The gear case cover mount water pumps have two cast slots in the water seal cavity. Effective with Engine Serial Number 6R2807 machined relief slots were added to the pump. The relief slots ensure coolant flow to the seal faces.

    Water Pump Body Modification (FM)

    NOTICE:

    If a vise is used to secure the water pump drive gear for locknut or impeller removal, use soft jaws on the vise and exercise extreme caution to prevent damage to the water pump drive gear teeth. ‪

    1. Lock the water pump body securely in the soft jaws of a bench vise.
    2. Using a die grinder (if possible, have professionally machined), remove 38.1 mm (1.5 in.) of material in the 10 o'clock and 4 o'clock positions of the raised belt that surrounds the water pump impeller. See Figure 20492 . Enough material should be removed so that, when machined, the slot is flush with the rest of the casting.
    3. After machining, wash the pump housing and all other pump parts in clean fuel oil.
    4. EYE INJURY

      To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.

    5. Dry with compressed air.

Cleaning of Front Mounted Water Pump

Clean the water pump parts as follows: ‪

  1. Wash all of the pump parts in clean fuel oil.

    EYE INJURY

    To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.

  2. Dry the parts with compressed air.

Assembly of Front Mounted Water Pump

Assemble the water pump as follows: ‪

  1. Coat the bearing bores of the water pump housing and the drive shaft bearing surfaces with clean engine oil.

    NOTICE:

    Although the bearings are identical, the bearings and races are matched parts, and should be installed as they are removed from the box. Parts that are not matched will cause damage to the water pump. ‪

  2. Assemble new bearing packs. See Figure 20465 .

    Bearing Pack Assembly (FM)

  3. Install the drive shaft into the center of the fixture usingJ 35988-18 andJ 35988-2 , parts of tool set J 35988-D . See Figure 20493 .

    Bearing Installation Set-Up (FM)

  4. Install the assembled bearing packs to the drive shaft. See Figure 20494 .

    Bearing Placement (FM)

  5. Press the bearing pack onto the shaft until it contacts the shoulder of the shaft using J 35988-1 , part of tool set J 35988-D . See Figure 40602 .

    Bearing Installation (FM)

  6. Remove the shaft and bearing assembly from the press.
Test Bearing Assembly (FM)

Check bearing assembly as follows: ‪

  1. Turn bearings to ensure they turn freely.
    1. If bearings bind, disassemble water pump and replace bearing assembly. Refer to section .
    2. If bearings do not bind, reuse the part.

Assembly of Water Pump (FM) - cont'd

Continue assembling the water pump, as follows: ‪

  1. Coat the new oil seal contact area of the water pump housing with a thin film of clean engine oil. See Figure 20496 .

    Oil Seal Contact Area Lubrication (FM)

  2. Install the oil seal to the water pump housing from the rear (gear side). See Figure 20497 .

    Oil Seal Positioning (FM)

  3. Place the small end of tool J 35988-1 , part of tool set J 35988-D , into the water pump housing until it contacts the oil seal. See Figure 40603 .

    Oil Seal Installation (FM)

    NOTICE:

    The contact surface of the oil seal is coated with a special sealant. Do NOT remove this sealant before installing the oil seal. If sealant is removed, leakage can occur. ‪

  4. Press the oil seal into the housing until the seal lip is bottomed in the pump housing. Remove the tool J 35988-1 , part of tool set J 35988-D .
  5. Coat the bearings with clean engine oil.
  6. Place the water pump housing, face down (gear side up), on a press bed.
  7. Install the drive shaft, with bearings installed, to the rear of the water pump housing. See Figure 20499 .

    Note: During the bearing installation, the water pump housing must be parallel to the press bed or table surface.

    Drive Shaft Insertion (FM)

  8. Place the large end of tool J 35988-1 , part of tool set J 35988-D , over the drive shaft so that the lip of the tool rests squarely on the outer bearing race. See Figure 40604 .

    Drive Shaft Installation (FM)

    NOTICE:

    The drive shaft must be installed pressing on the outer bearing race only. Any other attempt at installation may damage the bearings. ‪

  9. Press the drive shaft and bearing assembly into the water pump housing, using the tool J 35988-1 , part of tool set J 35988-D , until it is seated firmly against the shoulder in the housing.
  10. Install the snap ring to the water pump housing. See Figure 20501 .

    Snap Ring Installation (FM)

    NOTICE:

    Form-a-Gasket Sealer must be used sparingly, and kept from the shaft and bearing surfaces. Excessive amounts of Form-a-Gasket Sealer could cause plugging of radiator or cooler core. ‪

  11. Turn the water pump housing over. Working through the front, apply a coating of Aviation Form-a-Gasket, Form-a-Gasket No. 3 or equivalent to the area where the water pump seal case contacts the pump body. See Figure 20502 .

    Sealer Installation

  12. Install J 35988-3A , part of tool set J 35988-D , to the fixture tool. See Figure 20503 .

    Support Installation (FM)

  13. Install the water pump housing assembly to the fixture. See Figure 20504 .

    Water Pump Impeller Installation Set-Up (FM)

    NOTICE:

    The extension must contact and support the shaft when installing the water seal and impeller to prevent damage to the bearings. ‪

  14. Turn the adjustor wheel to raise the extension until it contacts the drive shaft in the water pump housing.
  15. Apply Loctite primer (Locquic Primer N, Part No. 764) by swabbing onto the I.D. of the rotor of the seal.
  16. Install a new water seal over the drive shaft and seat it in the water pump housing. See Figure 20505 .

    Water Seal Insertion (FM)

  17. Position tool J 35988-1 , part of tool set J 35988-D , over the water seal. See Figure 42248 .

    Water Seal Installation (FM)

  18. Press the water seal into the housing until the flange of the seal case contacts the water pump housing a full 360. Remove tool J 35988-19 , part of tool set J 35988-D .
  19. With the water pump housing still housed in toolJ 35988-2 , part of tool set J 35988-D , and located on a press bed, install the water pump impeller to the end of the drive shaft. Position the impeller so that the machined end is parallel with the housing machined face. See Figure 20508 .

    Water Pump Impeller Installation (FM)

  20. Press the impeller on until it is flush with the end of the drive shaft. See Figure 20509 .

    Water Pump Impeller Location (FM)

  21. Turn the housing over and place it face (impeller side) down on fixtureJ 35988-2 , part of tool set J 35988-D .
  22. Install the Woodruff key to its slot in the drive shaft. Tap the key with a brass hammer to seat it squarely in the slot. See Figure 20510 .

    Woodruff Key Installation (FM)

  23. Install the water pump drive gear to the drive shaft, indexing the slot in the gear with the Woodruff key.

    NOTICE:

    Extension tool J 35988-3 , part of tool set J 35988-D , must support the shaft. This is necessary to prevent damage to the bearings when pressing the gear onto the shaft. ‪

  24. Turn the adjustor wheel to raise the extension toolJ 35988-3 , part of tool set J 35988-D , until it contacts the shaft.
  25. Using the small end of toolJ 35988-1 , part of tool set J 35988-D , press the drive gear down onto the drive shaft until it touches the bearings. See Figure 20511 .

    Water Pump Drive Gear Installation (FM)

  26. Install locknut to the drive shaft threads. See Figure 20512 .

    Locknut Installation (FM)

  27. Using J 35988-5 , part of tool set J 35988-D , with a breaker bar to hold the gear and shaft, tighten the locknut with a torque wrench to 203-230 Nm (150-170 lbft) torque.
Assembly Integrity Test

Verify the assembly integrity as follows: ‪

  1. Turn the pump over and install J 35687 into the tapped holes provided in the impeller.
  2. Clamp J 35988-5 , part of tool set J 35988-D , (legs up) in a vise and position the lightening holes in the drive gear over the legs of the tool.
  3. Using a 1/2 in.-drive torque wrench in the hole provided in the center of J 35687 , apply 68 Nm (50 lbft) torque in either direction.
    1. The gear and impeller must withstand 68 Nm (50 lbft) torque without slipping.
    2. If the torque specification is not satisfied, disassemble water pump and replace the impeller. Refer to section .
  4. Using a dial indicator with magnetic base, measure the total run-out of the water pump drive gear at four places, at 90 degree intervals. Maximum allowable run-out is 0.0635 mm (0.0025 in.). See Figure 20513 .

    Measuring Water Pump Drive Gear Runout (FM)

    1. If specifications are exceeded, disassemble the water pump and check for burrs or foreign particles. Refer to section .
    2. If specifications are with limits, reuse part.

Installation of Front Mounted Water Pump

Install the water pump as follows: ‪

  1. Coat the two seal rings with clean engine oil. Install the larger seal ring to the groove in the water pump housing. Install the smaller seal ring to the groove in the water pump cover. Coat the water pump drive gear with clean engine oil.
  2. Install the water pump to the engine, meshing the water pump drive gear with the bull gear.
  3. Install the three water pump housing-to-gear case cover bolts. Tighten the bolts alternately and evenly to draw the water pump straight into the engine. Torque the bolts to 30-38 Nm (22-28 lbft).
  4. Measure the gear backlash. Refer to section .
  5. Install the water pump cover to the water pump with two bolts. Torque the bolts alternately and evenly to draw the cover straight into the water pump housing. Torque the bolts to 30-38 Nm (22-28 lbft).
  6. Slide the coolant hoses into position and tighten the hose clamps.
  7. Fill the cooling system. Refer to section of engine maintenance.