TESTING AND ADJUSTING
Unless the same impeller or one like it is used and
4. Keep the temperature of the water at 1970 F (92 C)
positioned on the shaft correctly, it is possible for a rebuilt
for ten minutes. Make the water move around. This
water pump not to give enough flow of coolant to cool the
keeps all of the water at the same temperature.
engine. If the one who rebuilt the water pump used an
impeller with a design different from the original
5. After ten minutes, remove the regulator and
equipment water pump, be sure the output of his rebuilt
immediately measure the distance the regulator is
water pump is as good as the original equipment water
opened. The distance must be a mini- mum of .380
in. (9.65 mm).
Here is how to check a rebuilt water pump:
FAN BELT ADJUSTMENT
1. Bearing end clearance must be .001 to .025 in. (0.03
Make an adjustment to the belt farthest from the
to 0.64 mm).
engine. Correct belt adjustment must give the following
reading using a Burroughs Gauge No, BT-33-96-4-15 or a
2. The clearance (2) between the face of the impeller
and the front cover is .011 to .035 in. (0.28 to 0.89
New belt ............ ... 120 ± 5 Gauge reading.
Belt with a minimum of 30 minutes
of operation time .....
90 ± 10 Gauge reading.
WATER PUMP PRESSURE CHECK
9S8138 Pressure Gauge.
The pressure at the outlet for the water pump tells if
the shunt system and water pump are operating correctly.
To check the pump pressure, install pressure gauge (2) in
the front cover. The pressure must be a minimum of 15
psi (1.05 kg/cm2 ) at 2800 rpm.
IMPELLER CLEARANCE AND HEIGHT
1. Front cover, 2. Impeller clearance [.011 to .035 In,
(0.28 to 0,B mm)]. 3, Impeller. 4, Impeller height [1.286
to 1,275 in. (32,12 to 32.39 mm)].
Clearance (2) is an indication of the condition of the
1, 3B7722 Bushing. 2.9S8138 Pressure Gauge.
impeller and of the location of the impeller on the shaft. It
can also be an indication of the condition of the bearing
If the pump pressure is less than the minimum
and front cover. Check the clearance of the impeller in
pressure: First, check the vent tube between the radiator
the following way.
top tank and the surge tank; it must have an inside
diameter of approximately .19 in. (4.8 mm).
a. Put a small amount of wax or a soft material on
two vanes of the impeller directly opposite of
Second, check to see that the shunt line has a
minimum inside diameter of .75 in. (19.1 mm).
b. Using a new gasket, install the water purity and
INSPECT REBUILT WATER PUMPS
tighten the bolts holding the water pump. DO
NOT turn the pulley.
The water pump is serviced only as a complete unit
and separate parts for the water pump are not available.
Push in on the pulley with a force of about 15 lbs.
Some others can be reconditioning these water pumps,
(7 kg). This will remove the end clearance.
using a different impeller, or an impeller they have
machined on the face for the seal or on the vanes.