MBW R422 - Manual (Page 14)

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10. Secure the cover with two flat head socket screws
(#20) torque to 8 ft lbs (11 N•m).
11. Remove the spring box tool rods from the assembly.
12. The spring box warning decal (page 2, #01326)
should be clean and highly visible. If not, the old decal
should be completely removed and replaced with a
new decal.
13. Lightly oil a new o-ring (#10) and place it into the
groove in the spring box guard (#13).
14. Slide the spring box guard over the ram head onto the
spring box. Be careful not to damage the o-ring
during installation.
15. Place the spring box assembly onto the shoe (#12)
with the fill plug (#4) pointing toward the back of the
shoe.
16. Install four socket head cap screws (#23) and lock
washers (#24). Torque the cap screws to 40 ft lbs (56
N•m).
Gearbox and Lower Unit Assembly
Refer to Gearbox and Lower Unit Assembly, page 18.
1. Rotate the ram head (page 16, #14) in the lower unit
so the larger hole on top is positioned toward the front
of the shoe (#11).
2. Slide the gearbox assembly onto the lower unit.
3. Align the connecting rod (page 14, #5) with the ram
head and install the piston connecting pin (#6) with
the threaded hole in the pin facing out.
4. Install retaining ring (#8) into ram head. Be sure
retaining ring is completely seated into groove in ram
head.
5. Rotate the gearbox assembly so the front of the
gearbox is aligned with the front of the lower unit.
6. Secure the lower bellows mount (page 16, #4) to the
spring box guard (page 16, #12) using six hex head
flange screws (page 16, #21). Torque to 12 ft lbs (16
N•m).
7. Tip the assembly back and place a new gasket (#3)
over the gearbox face.
8. Insert the dowel pins (#1) into the gearbox through
the holes in the gasket.
9. Align the holes in the cover (#2) with the dowel pins
and place the cover on the gasket.
10. Secure the cover to the gearbox using four flange
head screws (#8). Tighten the flange screws equally
and torque to 12 ft lbs (16 N•m).
11. The gasket will compress slightly after initial
tightening, re-torque the flange screws after 5
minutes.
12. If the lifting bracket & handle brackets (page 20, 12,
13 &19) were removed, reinstall with flange head cap
screws (page 20, 22 &23). Torque to 35 ft lbs (47
N•m).
13. Fill the unit with oil according to the Changing
Percussion System Oil section on page 6.