50, 50 Special, 51, and 55
Workshop Manual
531 03 00-76
This workshop manual is mainly intended for Husqvarna
50, 50 Special, 51, and 55 models, but certain chapters
can also be used for other models. The manual gives
information about how to repair the saw and how to use
special tools. In order to make sure that the saw will
function properly, always use Husqvarna original spare
parts and accessories.
The information, specifications and illustrations in this
manual are based on the information in effect at time of
printing. Any improvements or changes on these models
will be included in future manual revisions.
Page
Technical Specifications
2
Service Data
3
Service Tools
4 Safety Equipment
5 Rewind Starter
6
Ignition System
7 Centrifugal Clutch
8
Lubrication System, Oil Pump
9 Anti-Vibration System
10
Fuel System
Exhaust System
12 Cylinder & Piston
13 Crankcase & Crankshaft
2
3
3
4
12
15
22
26
30
32
47
46
51
Engine
Displacement - cc (cu. in.)
Bore - mm (in.)
Stroke - mm (in.)
Max. power of speed - rpm
Idling speed - rpm
Clutch engagement speed - rpm
No load free speed - rpm
Ignition system - Electroiux
Air gap - mm (in.)
Spark plug - Champion
NGK
Electrode gap - mm (in.)
49 (3.0)
44(1 .73)
32(1 .26)
8400
2500
3700
12500
ET
0.3 (0.012)
RCJ7Y
BPMR6A
0.5 (0.020)
51 (3.1)
45(1 .77)
32(1 .26)
8400
2500
3700
12500
ET
0.3 (0.012)
RCJ7Y
BPMR6A
0.5 (0.020)
51 (3.1)
45(1 .77)
32(1 .26)
9000
2500
3700
12500
ET
0.3 (0.012)
RCJ7Y
BPMR6A
0.5 (0.020)
53 (3.2)
46(1 .81 )
32(1 .26)
9000
2500
3700
12500
ET
0.3 (0.012)
RCJ7Y
BPMR6A
0.5 (0.020)
Fuel and Lubrication System
Carburetor - Walbro
WA82
WA82
WT170
WTl 70
Fuel tank volume - Iitre (pint)
0.6 (1 .27)
0.6 (1 .27)
0.6 (1 .27)
0.6 (1 .27)
Oil tank volume - Iitre (pint)
0.3 (0.63)
0.3 (0.63)
0.3 (0.63)
0.3 (0.63)
Oil pump capacity at 6000 rpm
cc/rein.
7.0
7.0
7.0
7.0
Oil pump type
Automatic
Automatic
Automatic
Automatic
Bar and Chain
Bar length
cm
inch
Chain pitch
Chain speed
.325 m/see
3/8 m/see.
Drive link gauge - mm (in.)
Weight - kg (Ibs)
Weight with 38 cm (15 in.)
guide bar