Troy-Bilt 52070, 52066 owner manual Maintenance Schedule, Adjusting Trimmer Head Engagement

Before each use.

Every 5 operating hours. Every 25 operating hours. Every 100 operating hours.

Section

5

Maintenance

13

WARNING

Before inspecting, cleaning or servicing the machine, shut off engine, wait for all moving parts to come to a complete stop, disconnect spark plug wire and move wire away from spark plug. Remove ignition key on electric start models.

Failure to follow these instructions can result in serious personal injury or prop- erty damage.

MAINTENANCE SCHEDULE

PROCEDURE	NOTES
Check motor oil level	2, 3
Check trimmer/mower lines	2, 6
Check trimmer head engagement	2
Engine/machine cleaning	2, 7, 8
Check nuts and bolts	2
Change motor oil	1, 11
Service air filter system	4, 11
Clean under deck	4
General lubrication	4
Inspect drive belt	5
Clean engine	2, 10
Check trimmer head wear cup	3, 9

NOTES

1 - After first 2 hours of break-in operation; every 25 hours thereafter.

2 -

3 -

4 -

5 -

6 - New line replacement is suggested when old line is 50% or less of original length.

7 - Clean daily in extremely dusty or dirty conditions.

8 - See Engine Owner’s Manual for service recommendations.

9 - Replace when severe gouges exist on bottom surface

10 - At each fuel refill.

11 - Service more often if used in extremely dusty

or dirty conditions (see Engine Owner’s Manual).

NOTE: LEFT and RIGHT sides of unit are as viewed from operator’s position behind the handlebars.

ADJUSTING TRIMMER

HEAD ENGAGEMENT

The tension on the drive belt must be cor- rect for proper operation of the trimmer head. If the tension is correct, the trim- mer head will rotate when the Trimmer Head Control Bail is pulled back against the handlebar (another indication of cor- rect tension is if the engine stalls when the trimmer head becomes bound up in very tough material).

A worn or loose drive belt will cause the trimmer head to move slowly – or not at all – when the control bail is engaged (belt squealing may also be noticeable).

If the tension is too tight, the trimmer head may rotate before the control bail is engaged, or when there is no free play in the control bail.

To Adjust Belt Tension

1.Stop the engine and wait for all parts to stop moving. Adjust the two jam nuts on the control cable adjustment stud (see Figure 5-1) as follows:

a.To tighten belt tension, thread the upper nut (A, Figure 5-1) upward one or two full turns, followed by the lower nut

(B). Tighten both nuts securely. Test unit and readjust jam nuts as needed.

b.To loosen belt tension, thread the lower nut (B) downward one or two full turns, followed by the upper nut (A). Tighten both nuts securely. Test unit and readjust jam nuts as needed.

A

B

Figure 5-1

REMOVING AND REPLACING THE TRIMMER HEAD

1.Stop the engine and wait for all moving parts to stop. Disconnect the spark plug wire and move it away from the spark plug. Remove the ignition key on electric start models.

2.Two bolts (A, Figure 5-2) secure the trimmer head (B) to the spindle head (C). Loosen both bolts (not the nuts) just enough to allow the trimmer head to slide down the spindle head and past the two stops. Do not attempt to remove the bolts

– they are permanently attached. NOTE: It may be necessary to remove the wear cup (D, Figure 5-2) when replacing the trim- mer head. See Step 4 for instructions.

3.Install the new trimmer head on the spindle head. Tighten the hardware securely (to 75 in/lbs.) and evenly.

4.Inspect the wear cup (D, Figure 5-2) for signs of severe wear, such as deep gouges. Use the following steps if the wear cup needs to be replaced:

a.Insert a Phillips head screwdriver into the small hole at the top, front of the deck (see Figure 5-5) and rotate the trimmer head until the screwdriver engages a hole in the trimmer head. This will prevent the trimmer head from turning when you next remove the hex nut (E, Figure 5-2).

b.Remove hex nut (E), washer (F) and wear cup (D). Install the new wear cup and reinstall the washer and hex nut.

Tighten securely and remove Phillips screwdriver from deck.

C

B

A

D

F

E

Figure 5-2