TM 5-3810-300-24&P-3
5.1
The centrifugal type water pump illustrated in Fig. 1
circulates the engine coolant through the cylinder block,
cylinder head, radiator, and the oil cooler. The drive end
of the pump shaft is supported by a sealed double-row
combination radial and thrust ball bearing. The pump
shaft serves as the inner race of the bearing.
A spring-loaded seal assembly and a water slinger,
located between the seal and the bearing, prevent the
coolant from passing along the shaft to the bearing. The
carbon washer in the seal assembly bears against a
steel insert that is pressed into the pump body. The
insert may be replaced when worn.
The impeller is a press fit on one end of a tapered
stainless steel shaft. Former pump assemblies used a
taper pin to hold the impeller on the shaft.
Fig. 2 - Water Pump Mounting
The pump is mounted at the front end of the blower (Fig.
2) and is driven by the lower blower rotor shaft. The
Remove Water Pump
drive coupling, pressed on the end of the pump shaft,
has an integral oil thrower that shrouds the flange end of
Refer to Figs. 2 and 3 and remove the pump as follows:
the pump body and deflects the oil away from the
1. Open the drain cock in the pump body and drain the
bearing.
cooling system.
2. Loosen the hose clamps and slide the water pump
Lubrication
inlet hose back against the pump cover.
3. Remove the two bolts and lock washers that attach
The sealed type ball bearing is filled with lubricant at the
the pump outlet flange to the cylinder block. Remove the
time it is assembled to the pump shaft, and no further
flange and packing ring.
lubrication is required.
4. Remove the three bolt and seal assemblies that
attach the pump to the blower assembly.
5. Withdraw the pump and remove the gasket.
Disassemble Water Pump
1. Remove the pump cover and gasket.
NOTE: Clean the corrosion from around the
impeller and shaft before separating the shaft
and bearing assembly from the impeller, seal
and water pump body.
2. Support the pump on its mounting flange in an arbor
press as shown in Fig. 4. Place a short rod on the end
of the shaft and press the shaft and bearing assembly
from the impeller, seal
Fig. I - Typical Water Pump Assembly
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