DEF Backflow Valve Replacement

DEF Backflow Valve Replacement

Follow the below information to properly replace the backflow connector.
1. Remove DEF supply pump cover. See figure 1.

NOTE: Wipe or blow away any debris, dirt or dust from top of the DEF supply pump to avoid contamination in the following steps.






Figure 1.
DEF Supply Pump Cover






Figure 2.

2. Remove back flow connector hose. See figure 2.
a. Push on the connection knob to release the hose.






Figure 3.
Backflow valve connector






Figure 4.
New Backflow connector

3. Using a 17mm deep socket, remove back flow connector and discard it. See figure 3.
4. Apply engine oil on O-ring of the new back flow connector (Figure 4) and install temporarily.

NOTE: Be sure to keep the backflow connector free from any dirt or debris to avoid SCR system contamination.

5. Using a 17mm deep socket, tighten the new backflow connector to 4 to 5Nm (35 to 44 lb in.) using torque wrench.
6. Insert back flow hose. The connection will make a click noise when completely inserted.
7. Clean away any DEF.
8. Reinstall the DEF supply pump cover.
9. Using IDSS clear any DTCs