Hitachi CH55EPA (S) Owner's Manual page 12

Cylinder (Engine cooling) (Fig. 3-5)
The engine is air cooled and air must circulate
freely around engine and over cooling fins on
cylinder head to prevent overheating.
Every 100 operating hours, or once a year
(more often if conditions require) clean fins and
external surfaces of engine of dust, dirt and oil
deposits which can contribute to improper cooling.
NOTE!
Do not operate engine with engine shroud or
muffler guard removed as this will cause
overheating and engine damage.
Cutter blade (Fig. 4-1, 2)
The blades are installed to the cutter guide with
three to five bolts depending on cutter length.
Those bolts are tightened with a clearance so
that the cutters can move smoothly.
When clearance is too small:
The cutters do not move properly and the
sliding surfaces may seize.
When clearance is too large:
The cutters are poor in sharpness.
To adjust the cutter clearance:
1. Loosen the cutter fixing nuts.
2. Fully tighten the cutter fixing bolts and then
loosen them approx. 1/2 turn.
3. With the bolts set at that position, tighten the
cutter fixing nuts.
Be sure to replace cutter guide fixing bolts
when they are loosened, worn or damaged.
Also be sure to replace damaged cutter blade.
NOTE!
Properly lubricate the cutter sliding surfaces
with machine oil.
Fig. 4-1
Gear case (Fig. 4-3)
Apply good quality lithium based grease
through the grease fittings.
On some models, one of the grease fittings has
been moved from upper location to the bottom.
NOTE!
Lubrication should be applied at 50 hour
intervals and more frequent at heavy use.
Maintenance schedule
Below you will find some general maintenance
instructions. For further information please
contact HITACHI dealer.
Daily maintenance
Clean the exterior of the unit.
Check the blade guard for damage or cracks.
Change the guard in case of impacts or cracks.
Check that the blade is sharp, and without
cracks.
Check that the blade nut is sufficiently tightened.
Make sure that the blade transport guard is
undamaged and that it can be securely fitted.
Check that nuts and screws are sufficiently
tightened.
Fig.3-5
Fig. 4-2
Weekly maintenance
Check the starter, especially cord and return
spring.
Clean the exterior of the spark plug.
Remove it and check the electrode gap.
Adjust it to 0.6 mm, or change the spark plug.
Clean the cooling fins on the cylinder and
check that the air intake at the starter is not
clogged.
Check that the angle gear is filled with grease.
Clean the air filter.
Monthly maintenance
Rinse the fuel tank with gasoline.
Clean the exterior of the carburetor and the
space around it.
Clean the fan and the space around it.
Fig. 4-3
GB-11