Stihl MS 251 User Manual

MS 251, MS 251 C
English
41
N Turn the guide bar over – every time
you sharpen the chain and every
time you replace the chain – this
helps avoid one-sided wear,
especially at the nose and
underside of the bar.
N Regularly clean the oil inlet hole (1),
the oilway (2) and the bar groove
(3).
N Measure the groove depth – with the
scale on the filing gauge (special
accessory) – in the area used most
for cutting.
If groove depth is less than specified:
N Replace the guide bar.
The drive link tangs will otherwise
scrape along the bottom of the groove –
the cutters and tie straps will not ride on
the bar rails.
Remove shroud
N Move the Master Control Lever to
the stop position 0
N Push the front hand guard forwards
– the saw chain is blocked
N Loosen screws (1)
N Remove the shroud (2)
Refitting the shroud
N Refit the shroud and tighten the
screws
Taking Care of the Guide Bar
2
3
1
143BA026 KN
Chain
type
Chain pitch Minimum
groove depth
Picco 1/4" P 0.16" (4.0 mm)
Rapid 1/4" 0.16" (4.0 mm)
Picco 3/8" P 0.20" (5.0 mm)
Rapid 3/8"; 0.325" 0.24" (6.0 mm)
Rapid 0.404" 0.28" (7.0 mm)
Shroud
1
1
1
2710BA003 KN
2

Stihl MS 251 Specifications

General

Idle speed	2800 RPM
Motor type	2-stroke motor
Chain pitch	1/308 \
Blade length	450 mm
Product color	Black, Grey, Orange
Motor speed (max)	10000 RPM
Oil tank capacity	0.2 L
Fuel tank capacity	0.39 L
Engine displacement	45.6 cm³
Kickback protection	Yes
Engine power	3 hp
Power source	Gasoline
Sound power level	114 dB
Vibration emission	3.9 m/s²
Sound pressure level	103 dB

Weight and Dimensions

Weight	4900 g