Hitachi EM 490 - Manual (Page 18)

307-735 18
REPLACING THE CONNECTING ROD and BEARING
WARNING
To reduce the risk of serious bodily injury, including
fluid injection or splashing in the eyes or on the skin,
or injury from moving parts, always follow the Pres-
sure Relief Procedure Warning on page 14 be-
fore checking, adjusting, cleaning or shutting off the
sprayer.
Unplug the power supply cord.
NOTE: Refer to Fig 16 for this procedure unless other-
wise instructed.
1. Remove pump as described on page 16.
2. Remove the front cover (35).
3. Remove the bearing housing screws (20).
4. Slide the bearing and connecting rod assembly (A) off
the crankshaft (B).
5. Use a screwdriver to push the retaining spring (33)
up. Remove the pin (34) and the coupling (36).
6. Clean and inspect the bearing housing (53) and con-
necting rod (54), including the needle bearing (D). Re-
place both parts if either is worn or damaged.
7. Clean and inspect the crankshaft (B). Wipe the crank-
shaft clean with a rag (don’t use solvent). If the crank-
shaft is badly worn, replace the drive assembly (55)
as described on page 19.
CAUTION
To extend the service life of the connecting rod bear-
ing, lubricate it properly. After every 100 hours of op-
eration, or whenever servicing the pump (whichever
comes first), fill the cavity (E) in the connecting rod
(54) with SAE non–detergent motor oil.
8. Coat the surfaces of the new connecting rod and
bearing (C) with SAE non–detergent motor oil. Liber-
ally pack the needle bearing (D) with industrial-grade,
heavy-duty, extreme-pressure, lithium-soap grease.
9. Assemble the connecting rod (54) and bearing (53).
Assemble the coupling (36) to the connecting rod and
install the pin (34). Push the spring (33) over both
ends of the pin (34).
10. Align the connecting rod (54) with the crankshaft (B)
and push the bearing housing onto the drive housing
(55). Assemble the remaining parts.
53
Fig 16
55
18
20
35
19
34
36
33
LUBRICATE:
See CAUTION
54
A
B
C
D E