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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 Husqvarna Power Cutters Workshop Manual Supplement for models 371K and 3120K 101 90 71-26 www.mymowerparts.com...
For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CONTENTS Workshop manual – power cutters Supplement for models 371K and 3120K Contents Filter system ............ 3 Carburettor ............5 Clutch ............... 6 Ignition system ..........6 Cutting head ............ 7 Tools ..............9 Cutting equipment .........
50 µm down to 5 µm. (It takes about 2 minutes for a 10 µm stone particle to fall one metre in stationary air). One physical property that is vital to the effectiveness of Husqvarna Air Injection Filtration is the way that the size of dust particles affects their behaviour in a stream of air: A small particle is affected more by a moving air stream than a large particle.
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The obvious practical benefit of Air Injection is that the service interval is consid- erably longer than with previous systems. 1. Centrifugal cleaning is the first stage of filtering the intake air on the 371K/ 3120K Air injection. Centrifugal cleaning was originally only used on larger ma- chines in dusty environments, e.g.
(weight) of the parts, the greater the effect. (Lightweight parts can accommodate fluctuating vibration more easily than heavy parts). The moving parts of the carburettor are larger in large machines, and the 371K and 3120K Air Injection therefore have a vibration-damping element between the cylinder and carburettor.
CLUTCH Self-lubricating clutch bearing The clutch bearing fitted to the 371K and 3120K Air Injection is lubricated automati- cally, which is an old Husqvarna speciality. A channel through the crankshaft has a vent under the clutch bearing. The positive pressure that is developed inside the crankcase is transferred to the clutch bearing.
CUTTING HEAD Belt drive As with most other Husqvarna power cutters, the cutting disc on the 371K/3120K Air Injection is driven by a drive belt running between the pulley on the crankcase and the pulley on the drive shaft. As well as being simple, this type of transmission is also lightweight.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING HEAD Reversible arm The cutting arm can be reversed on the machine. This makes it possible to cut right up against a wall or floor as close as the disc guard allows, i.e. around 20 mm from the cutting disc.
For Husqvarna Parts Call 606-678-9623 or 606-561-4983 TOOLS Drift for ball-bearing Drift Allen key NV 4 M Combination tool NV 13/19 English – www.mymowerparts.com...
The belt is subjected to hard, uneven loading. The pulleys also have relatively small radii, which places special quality requirements on the belt. Always replace the belt with an original Husqvarna belt that has been thoroughly tested to meet these special requirements.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING EQUIPMENT Remove the pulley from the cutting arm. Lock the pulley using a suitable drift and unscrew the bolt that holds the pulley. Lift off the pulley and the washer that is between the pulley and the ball- bearing.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING EQUIPMENT Refitting Do as follows! Models 371K, 3120K Models 371K, 3120K Clean and inspect the various parts. Clean and inspect the various parts. Heat up the cutting arm and fit new Replace the cutting arm mounting bolts bearings.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING EQUIPMENT Drive the shaft in through the bearings Drive in the shaft using a plastic mallet until it projects out 5.5 mm on the other so that it goes through the ball-bearings side.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING EQUIPMENT Clean, refit and adjust. Clean and replace damaged or worn parts of the belt tensioning mechanism before fitting. Lift the cutting arm into position and fit Lift the cutting arm into position. Place...
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Fig. D. Uneven wear caused by belt being too loose or engine idle speed being too high. Fig. E. Tears in belt and damaged reinforcement caused by poor alignment, oil on pulleys or substandard belt. Use Husqvarna original belts. Fit a new belt around the clutch drum Fit a new drive belt around the clutch and fit the cutting arm in its rearmost drum.
Disc diameter The disc diameter is given in mm or inches. Husqvarna 371K Air Injection can be used with the following cutting discs: 12" (300 mm), 14" (350 mm) or 16" (400 mm).
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• Husqvarna Rescue is a special blade with carbide bits. It can only be used by trained personnel in rescue work. Replaceable disc bushings Husqvarna power cutters can be fitted with a centre bushing to fit various standard disc sizes.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 CUTTING DISCS Which type of disc should I use? Hard steel Stainless Soft steel Granite Hard brick Pre-cast Hard General Concrete Abrasive Soft brick Green Asphalt steel concrete concrete concrete building concrete + other...
For Husqvarna Parts Call 606-678-9623 or 606-561-4983 WET-CUTTING WITH DIAMOND DISCS Wet-cutting practically eliminates cutting dust, while also cooling the cutting disc, which extends its working life. The disc guard has been prepared to accept Husqvarna’s wet-cutting kit. The wet-cutting kit has been rede- signed and can be fitted very quickly.
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For Husqvarna Parts Call 606-678-9623 or 606-561-4983 Husqvarna 1999-10 Printed in U.S.A. www.mymowerparts.com...