Kohler LH630-775 Service Manual page 142

Section 10
Inspection and Reconditioning
Figure 10-19. Water Pump.
The impeller assembly is not serviceable, but it
should be inspected for wear or damage.
1. Inspect the impeller to make sure the blades are
in good condition and free of any cracks, nicks, or
damage.
2. The impeller shaft should rotate smoothly,
without binding or wobbling, and there should
be no sign that coolant has leaked past the shaft
to the outer surface of the cover.
3. Check that the drive pulley is not cracked or
damaged in any way.
If your inspection causes you to doubt its reliability,
the water pump assembly should be replaced.
Always use a new O-Ring whenever the water pump
is removed. Do not reuse the old O-Ring or try to use
RTV in its place.
Cooling Fan and Drive
The cooling fan assembly consists of a fan attached to
a v-pulley and bearing carrier (hub), rotating on a
dual ball-bearing fan shaft (arbor). The assembly is
mounted with a bracket to the intake manifold and
driven via a split pulley off the flywheel. See Figure
10-20.
10.14
Figure 10-20. Front View of Engine Cooling System.
Inspect the components carefully for signs of wear or
damage.
1. Inspect the fan to make sure the blades are in
good condition and free of any cracks, nicks, or
damage. The area around the fan mounting holes
must also be free of any cracks or damage.
Figure 10-21. Fan Assembly (Pulley Side).
2. The fan and hub assembly, when mounted to the
center arbor shaft, must rotate smoothly
without noticeable bearing play, wobble, or
binding.
3. Check the v-belt for excessive wear, cracking or
damage. If proper belt tension cannot be
obtained, or the condition of the belt is suspect;
replace it with Kohler Part No. 66 203 02-S. Do
not use a substitute belt.