John Deere — Flushing Cooling System

Maintenance

From a John Deere owner's manual covering: 4045TF120, 6068HF158, 6068TF120, 6068TF250. Check it applies to your exact model before use.

Applies to: John Deere 4045TF120, John Deere 6068TF120, John Deere 6068TF250

Procedure

1. Pressure test entire cooling system and pressure cap if not previously done.
2. Slowly open engine cooling system filler cap or radiator cap to relieve pressure.
3. Open engine block drain valve on left side of engine. Drain all coolant from engine block.
4. Open radiator drain valve. Drain all coolant from radiator.
5. Remove thermostats. Install cover (without thermostats) using old gasket; tighten cap screws to 47 N·m (35 lb-ft).
6. Close all drain valves after coolant has drained.
7. Fill cooling system with clean water. Run engine about 10 minutes to stir up rust or sediment.
8. Stop engine, pull off lower radiator hose and remove radiator cap. Immediately drain water.
9. Close drain valves, reinstall radiator cap and hose. Fill with clean water and a heavy duty cooling system cleaner such as Fleetguard RESTORE and RESTORE PLUS.
10. After cleaning, drain cleaner and fill with water to flush. Run engine about 10 minutes, then drain.
11. Close all drain valves. Reinstall radiator hose and tighten clamps. Install thermostats using a new gasket.
12. Add coolant to radiator until coolant touches bottom of filler neck. Install radiator cap.
13. Run engine until it reaches operating temperature.
14. After running engine, check coolant level and entire cooling system for leaks.

Full service-parts list: John Deere 6068TF250 →

Source: John Deere owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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