Cutter Blade Adjustment
WARNING!
The cutter blades are very sharp! Always wear gloves when working around the cutter assembly.
CAUTION!
Operating the trimmer with worn or improperly adjusted cutters will reduce cutter performance and may also dam- age your machine.
Cutter performance of your machine depends in great measure on cutter blade clearance. Properly adjusted blades will oscillate freely yet help prevent binding of cut material between blades. Adjust blades as follows (Figure 26):
1.Loosen all blade locknuts at least one full turn.
2.Tighten each blade shoulder bolt firmly, and then loosen the shoulder bolts 1/4 to 1/2 turn.
3.Working from the gearcase end, lock each bolt in place by firmly tightening its locknut while preventing the shoul- der bolt from turning.
When shoulder bolt adjustment is cor- rect, there should be a gap of
mmbetween the cutter blades and the flat washers, and the flat washer beneath each bolt head should turn freely.
Locknut
Guide Bar
Cutter Blades | Washer |
Shoulder | (should turn |
Bolt | freely) |
Figure 26 |
|
10-Hour Maintenance
(more frequently in dusty conditions)
1.Remove the air cleaner cover by loosen- ing the thumb screws and lifting up. See Figure 27A.
2.Remove and inspect the
3.Clean the
4.Inspect the air cleaner element. If the element is damaged or distorted, re- place it with a new one.
5.Tap filter gently on a hard surface to dislodge debris from element or use compressed air from the inside to blow debris out and away from the air filter element.
Unscrew
Fasteners
Figure 27A
IMPORTANT!
Direct the air stream at the inside face of the filter only!
6.Install the filter element,
Filter
Element
Figure 27B
CAUTION!
Never operate the unit if the air cleaner assembly is damaged or missing!
10/15-Hour Maintenance
CAUTION!
Before removing the spark plug, clean the area around the plug to prevent dirt and dust from getting into the engine’s internal parts.
Every 10 to 15 hours of operation:
nRemove and clean the spark plug. See Figure 19. Adjust the spark plug electrode gap to 0.024 inch (0.6 mm). If the plug must be replaced, use only: NGK CMR5H or equivalent.
nLubricate the cutter assembly gear- box by pumping one or two strokes of
| Clean the spark |
| plug and check |
| the gap at the |
| electrode. |
| 0.024 inch |
| (0.6 mm) |
Figure 28 | 251030 |
CAUTION!
Over lubricating can cause the gear- box to operate sluggishly and can cause grease to leak out.
Gearbox Grease
Fitting
Figure 29
12