DEF Dosing Unit Filter—Final Tier 4/Stage IV Engine

Avoid contact with eyes. In case of contact, immediately flush eyes with large amounts of water for a minimum of 15 minutes. Reference the Materials Safety Data Sheet (MSDS) for additional information.

If DEF is spilled or contacts any surface other than the storage tank, immediately clean the surface with clear water. DEF is corrosive to painted and unpainted metallic surfaces and can distort some plastic and rubber components.

Spilled DEF, if left to dry or if only wiped away with a cloth, leaves a white residue. Improperly cleaned DEF spill can interfere with diagnosis of Selective Catalytic Reduction (SCR) system leakage problems.

Servicing DEF dosing unit filter may require removing additional covers or components. See Access DEF Dosing Unit for location information.

1. 
   RG22534-UN-21MAR13

   Remove DEF dosing unit filter cover (A).

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2. Remove and discard DEF dosing unit filter equalizing element (B).

3. Insert “Black” end of DEF dosing unit filter tool (C) into DEF dosing unit filter (D) until CLICK is felt or heard indicating DEF dosing unit filter tool is fully engaged.

4. A tool such as a screwdriver can be inserted into DEF dosing unit filter tool slot to assist removal.

   Pull DEF dosing unit filter tool and DEF dosing unit filter from DEF dosing unit. Discard DEF dosing unit filter and DEF dosing unit filter tool.

5. Plugged DEF dosing unit filter may indicate that header filter is also plugged.

   Examine dosing unit filter. If filter is plugged with contaminants, go to step 6. If not plugged, go to step 10.

6. Change DEF header filter. See Header Filter in this Operator’s Manual section.

7. Check DEF tank for contaminated DEF. See Testing Diesel Exhaust Fluid (DEF) in Diesel Exhaust Fluid (DEF) section of this Operator’s Manual.

8. If DEF is contaminated, drain and clean DEF tank. See Diesel Exhaust Fluid (DEF) Tank in Service - Clean section of this Operator’s Manual.

9. Check stored DEF supply. See Testing Diesel Exhaust Fluid (DEF) in Diesel Exhaust Fluid (DEF) section of this Operator’s Manual.

10. Clean DEF dosing unit threads and mating surfaces with distilled water.

11. Lubricate new DEF filter O-rings with clean engine oil. Carefully insert DEF dosing unit filter into DEF dosing unit.

12. Install new DEF dosing unit filter equalizing element into DEF dosing unit filter.

13. Install DEF dosing unit filter cover and tighten to specifications.

    DEF Dosing Unit Filter Cover	Torque	23 N·m (204 lb.-in.)