SO53 3LE
Customer Helpline 0845 600 5526 Monday to Friday 09.00 to 17.00
www.JCBdiy.com
WARNING
Before first use, it is essential that you ensure the bar and chain have not become
loose in transit. Never operate a chainsaw with incorrectly adjusted chains. Failure to
follow these steps could result in severe personal injury.
ADJUSTING THE CHAIN TENSION
See Figures 2-3, 37, 42-45.
WARNING
Never touch or adjust the chain while the motor is running. The saw chain is very sharp.
Always wear protective gloves when performing maintenance on the chain.
i.
Stop the engine before setting the chain tension.
ii. Slightly loosen the clutch cover lock knob by pressing in and rotating counter
clockwise (Figure 37).
iii. Turn the chain tension dial clockwise to tension the chain (Figure 44).
Note:
A cold chain is correctly tensioned when there is no slack on the underside
of the guide bar, the chain is snug, and it can be turned by hand without binding.
iv. Re-tension the chain whenever the flats on the drive links hang out of the bar
groove (Figure 3).
Note:
During normal saw operation, the temperature of the chain increases. The
drive links of a correctly tensioned warm chain will hang approximately 1.2 mm out
of the bar groove. The tip of the combination wrench can be used as a guide to help
determine the correct warm chain tension.
Note:
New chains tend to stretch; check the chain tension frequently and tension
as required. This applies for a NEW tool.
v. Lift the tip of the guide bar up to check for sag (Figure 43).
vi. Release the tip of the guide bar and turn the chain tension dial clockwise. Repeat
this process until the sag does not exist.
vii. Hold the tip of the guide bar up and tighten the clutch cover lock knob securely.
The chain is correctly tensioned when there is no sag on the underside of the
guide bar, the chain is snug, but it can be turned by hand without binding. Ensure
that the chain brake is not set.
Note:
If chain is too tight, it will not rotate. Loosen the clutch cover lock knob by
pressing in and slightly rotating counter clockwise, then rotate the chain tension dial
counter clockwise. Lift the tip of the guide bar up and re-tighten the clutch cover lock
knob securely. Ensure that the chain will rotate without binding.
CAUTION
A chain tensioned while warm may be too tight upon cooling.
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