Cub Cadet 6X4 Shop Handbook page 247

4g. Remove the air vent plug from the to-radi-
ator pipe, above the thermostat housing.
A 3/16" allen wrench will fit the plug.
See Figure 8.62.
Vent
plug
Figure 8.62
NOTE: Production versions may use a hex-
head plug: 7/16" wrench size.
4h. Position a drain pan under the engine tray.
4i. Remove the square drain plug from the
base of the water jacket on the inboard
side of the engine block using a 3/8"
wrench. See Figure 8.63.
Drain plug
Figure 8.63
4j. Allow the remainder of the fluid to drain.
4k. Empty the coolant reservoir using a
syphon pump.
Chapter 8 - Caterpillar Engine and Related Systems
NOTE: With the plugs removed, it is acceptable
to apply 30 PSI (2.0 Bar) of pressure with a
blow-gun to drive the coolant from the system.
This is about twice the pressure the system was
designed to hold, so it should only be done if
there are substantial openings in the system.
CAUTION: Wear eye protection when using
compressed air to force water out of the system.
CAUTION: Clean-up any spilled coolant immedi-
ately, and dispose of it in a safe, legal, and envi-
ronmentally responsible manner.
4l. Apply thread sealant to the block drain
plug and reinstall it immediately after
draining is complete.
4m. Make any needed repairs to the cooling
system while the fluid is drained.
4n. Re-connect the return hose to the return
pipe.
4o. Add 5 U.S.Qt. (4.73 L) of coolant to the
system through the radiator filler neck.
NOTE: Coolant requirements are described at
the opening of the COOLING SYSTEM MAIN-
TENANCE section of this chapter.
NOTE: Do not add coolant faster than 1.3 U.S.
gal. (5.0L) per minute to avoid air locks.
4p. Add coolant until liquid comes out of the
air vent port on the highest point of the to-
radiator pipe. See Figure 8.64.
Vent plug
removed
243
Figure 8.64