Toro 25430A Operator's Manual page 56

Figure 78
1. Drain hose
2. Drain valve
4. Open the drain valve on the radiator, and allow the
coolant to drain completely.
Note: Dispose of the used coolant properly according
to local codes.
5. Close the drain valve (Figure 78).
Flushing the Cooling System
Engine and radiator coolant capacity: 17.2 liter (18.2 US
qt)
1. Condition the cooling system as follows:
A. Ensure that the coolant is drained from the
radiator and that the drain valve is closed.
B. Open the vent valve (Figure 76).
C. Add a cooling system cleaning solution to the to
the radiator through the filler neck (Figure 79).
Note: Use cleaning solution of sodium carbonate
and water (or a commercially available equivalent).
Follow the directions that come with the cleaning
solution.
3. Radiator shroud (lower-left
area)
1. Coolant system cleaning
solution
2. Funnel
D. Close the vent valve.
Important: Do not install the radiator cap.
E. Operate the engine for 5 minutes or until the
coolant temperature gauge in the instrument
cluster indicates 82°C (180°F), then stop the
engine (Figure 80).
CAUTION
The cleaning solution is hot and can
cause burns.
Stay away from the discharge end of the
coolant drain hose.
F. Open the drain valve and drain the cleaning
solution into a drain pan (Figure 78).
G. Close the drain valve.
2. Flush the cooling system as follows:
A. Open the vent valve (Figure 76).
B. Fill the radiator with clean water (Figure 81).
56
Figure 79
3. Filler neck (radiator)
Figure 80