105681-4450 ZEXEL 9 420 616 547 BOSCH AUTOM. ADVANCE MECHANISM 9420616547 1056814450

Location of Components
Illustration 1 g06494607
Typical example
(A) DEF tank breather
(B) Heater relay
(C) DEF fast fill tank-mounted valve
(D) Plug heater
(E) Heated supply line
(F) DEF fast fill receiver
(G) DEF tank
Illustration 2 g06494608
(C) DEF fast fill tank-mounted valveThe ground level DEF fill system works much like the ground level fast fuel system. DEF fast fill tank-mounted valve (C) is mounted in DEF tank (G). Fast fill tank-mounted valve (C) has a piston that is normally closed with a spring.
Illustration 3 g06516649
(H) O-Ring seal
(J) Flow In
(K) Flow Out
(L) Back cavityNote: O-Ring seal (H) allows small amount of fluid flow.Note: The main flow through the valve is not shown.Note: During normal flow conditions there is no pressure built up in back cavity (L). Back cavity (L) is essentially "open to atmosphere".When filling, the DEF flow opens the piston, past the diverter shield and a portion flows through an orifice in the piston into the float area.
Illustration 4 g06516652
(L) Back cavity
(M) Rolling diaphragm
(N) O-Ring seal
(P) Drain holeNote: O-Ring seal (N) prevents any flow from back cavity (L).Note: Once the float rises, the pressure in back cavity (L) equals the pressure pushing the front of rolling diaphragm (M). Since the area behind rolling diaphragm (M) is greater than the area in front, along with the spring force, diaphragm (M) is held shut.When the tank level causes the float to rise high enough, the orifice is blocked, causing increased pressure on the piston until valve (C) closes. The increased pressure in the fill line then causes the nozzle attached to the receiver to shut off.The nozzle shuts off when the nozzle sees 172 to 200 kPa (25 to 29 psi) resistance. If pressure is not great enough from the source pump/supply at nozzle, there is not enough pressure built up in line between valve and nozzle to trigger nozzle shut off and DEF exits the breather-overfill.Targeted flow for the DEF supply pump should be 45 L/min (12 US gpm). Excessive flow can lead to premature shut-off of DEF nozzle.DEF tank valve (C), supply line (E), and DEF fast fill receiver (F) are electrically heated based on ambient temperature, battery, and alternator loads controlled through heater relay (B). For heated DEF hose repair kit, refer to Service Magazine, M0103829, "Repair Kits for Quick Connect Diesel Exhaust Fluid (DEF) Line Fittings Are Now Available for Certain Cat® Machine Engines".Note: If receiver (F) and supply line (E) on machine are drained for storage, the system must be refilled via the ground fill connection. The system is refilled to ensure that plug heater (D) in receiver (F) remains submerged in DEF fluid during the heating operation.
Plug heater (D) probe must be submerged at least 80% in DEF fluid to prevent overheating that could lead to plug heater (D) failing.