Usage:
3406E (2WS476-Up, 1MM127-Up) Truck Engines
Reference: Service Manual Module; SENR5016-00; Disassembly & Assembly; 3406E Truck Engine.
Description of Change: A new two-piece spool and diaphragm are now available to be installed in the BrakeSaver control valve for the above 3406E truck engines. The new design replaces the one-piece spool and diaphragm. The new two-piece spool has an increased service life.
Adaptable To: The new 154-1907 Spool replaces the 6P-4638 Spool. The new 158-0507 Diaphragm (orange color) replaces the 9Y-4811 Diaphragm (black color). The new spool and diaphragm must be installed together as they cannot be mixed.
The instructions have changed for installation of the new two-piece spool and diaphragm.
The following steps are for the assembly of the BrakeSaver control valve. The numbering scheme used in the figure is consistent with that used in the 3406E Disassembly & Assembly Manual (the same number references the corresponding part in the new assembly)
1. Put diaphragm (12) in position on valve retainer (14).
2. Align the hole in valve stop (13) with the pin in valve retainer (14) and install the stop.
3. Install bolt (11). Two no. 10-24 bolts installed in the stem of the retainer may be used in order to hold the retainer while torque is applied to the bolt. Do not damage the pilot surface on the retainer stem or the diaphragm rolling surface on the retainer while installing the bolt.
4. Install the thrust races (15) on either side of bearing (16) on the stem of the retainer (14).
5. Insert the stem of the retainer (14) into the pilot hole of the spool (8).
6. Install sleeves (5) and the O-ring seals.
7. Put spring (7), stop (10), spring (6), and slug (9) in position in valve spool (8).
8. Install valve spool (8) and retainer (14) into the valve body. As the valve is installed, make sure the edge of the diaphragm makes contact all of the way around with the groove in the valve body. At this time the valve retainer end must extend approximately 38.1 mm (1.50) in) from the valve body. Push the valve spool-retainer assembly approximately 6.4 mm to 12.7 mm (.2519 in to .50 in) farther into the valve body until a curved depression is caused in the diaphragm between the valve retainer and the valve body. Make sure there are not wrinkles in the diaphragm.
9. Install covers (3) and (4) on the valve body.
10. Install one O-ring seal (1), and two O-ring seals (2).
End By: Install the BrakeSaver control valve.