Workshop Manual, 42/42D/242, 1995-01, Chain Saw...42, 42D, 242 Workshop Manual 531 03 01-21 For Husqvarna Parts Call 606-678-9623 or 606-561-4983 Introduction The procedures included

42, 42D, 242Workshop Manual

531 03 01-21

For Husqvarna Parts Call 606-678-9623 or 606-561-4983

www.mymowerparts.com

Introduction

The procedures included in this workshopmanual are designed to provide you, the tech-nician, with the necessary information for repairand service of models 42, 42D and 242 chainsaws.

The information, specifications and illustrationsin this publication are based on the informationin effect at time of printing. Continued productimprovement may result in changes to thesesaws that may not be included in this manual.Later editions are revised to include any prod-uct changes that may have occurred.

Safety StatementsThe following safety statements are foundthroughout this manual and are designed tomake you aware of potential hazards or unsafepractices.

- WARNING -Immediate hazards which canresult in severe injury or death.

CAUTION: Hazards or unsafe practiceswhich can result in severe personal injury.

IMPORTANT: Hazards or unsafe practiceswhich can result in product or propertydamage.

NOTE: Additional pertinent information.



Table of Contents

= P a g e N o . Section

© Husqvarna Forest& Garden 1995

1



Technical Specifications

EngineDisplacement -----------------------------------------------------------Bore -----------------------------------------------------------------------Stroke ---------------------------------------------------------------------Maximum No Load RPM

Model 242 -----------------------------------------------------------Model 42(D) ---------------------------------------------------------

Idling Speed -------------------------------------------------------------Clutch Engagement Speed ------------------------------------------

Fuel and Chain Lubrication SystemCarburetor ---------------------------------------------------------------Fuel Tank Volume ------------------------------------------------------Oil Pump Capacity -----------------------------------------------------Oil Tank Volume --------------------------------------------------------

Ignition SystemIgnition System ---------------------------------------------------------Air Gap -------------------------------------------------------------------Spark Plug ---------------------------------------------------------------

Electrode Gap -----------------------------------------------------------

Heated HandlesModel 242 ----------------------------------------------------------------Model 42(D) -------------------------------------------------------------

Bar and ChainBar Length Minto Max -----------------------------------------------Drive Sprocket ----------------------------------------------------------Chain Speed

Model 242 -----------------------------------------------------------Model 42(D) ---------------------------------------------------------

Chain Pitch --------------------------------------------------------------Drive Link Gauge ------------------------------------------------------

WeightModel 242 ----------------------------------------------------------------Model 42(D) -------------------------------------------------------------

Weight with 13 inch Guide Bar and ChainModel 242 ----------------------------------------------------------------Model 42(D) -------------------------------------------------------------

42.0 cc (2.5 cu. in.)42.0 mm30.0 mm

15500rpm13000 rpm2900 rpm3900 rpm

Walbro HDA 340.5 Iitres (1.1 pints)3-7 cc/rein at 9000 rpm0.27 Iitres (0.55 pints)

SEM AM70.3 mm (.012 inch)NGK-BPMR6ACHAMPION-RCJ7Y0.5 mm (.02 inch)

65 watts at 10000 rpmNA

13-18 inches (33 -46 cm)7 tooth

19.7 m/secat9000 rpm17.3 m/secat9000 rpm0.325 inches1.5 mm (.058 inches)

4.6 kg (10.1 Ibs)4.5 kg (9.9 Ibs)

5.3 kg (1 1.7 Ibs)5.2 kg (1 1.4 Ibs)



Service Tools 2

5025006-01

5025026-01

5025030-07

5025033-015025038-01

5025067-015025070-01

5025079-01

5025082-01

5025083-01

5053818-175025134-02

5025149-015025161.01

50271 13-01

5027114-01

Assembling pliers, spark plug

Puller screw

Crankshaft installer

Piston stop

Pressure gauge

Wrench (11 mm)

Piston ring compressor

Seal Installer

Drift

Hook for fuel filter

Oil gear puller

Air gap gauge

Holding bar for flywheel puller

Crankcase puller

Test plug

Tachometer



3 Safety Equipment

Chain Brake

Disassembly

Disengage chain brake. Remove clutch coverretaining nut and remove cover. Clean chainbrake and clutch cover assembly,

Remove hand guard retaining screw. Rethreadscrew into pivot sleeve two turns. Press onscrew head to drive out inner pivot sleeve half.

Turn cover to opposite side. Using a suitablepunch, remove outer half of pivot sleeve.Separate hand guard from cover.

4



Safety Equipment 3Remove screws (4) and cover plate.

– WARNING -Wear eye protection whenremoving spring to preventinjury

Using a screwdriver, pry out brake spring.

Using a punch, drive out knee link retainingpin.

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3 Safety Equipment

Position punch in clutch cover as shown, anddrive out brake band roll pin. Remove brakeband and knee link assembly.

Check brake band for damage or wear. Thebrake band thickness should not be less than0.75 mm (.030”) when measured at any pointalong the band.

The brake band must be replaced if the band isdamaged or worn less than minimum thick-ness. If brake band requires replacement,remove screw and replace band.

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Safety Equipment 3Apply a thin coating of oil to brake mechanismparts. Position brake band and knee link incover.

Install knee link assembly and roll pins. Installspring on knee link mechanism.

- WARNING -Wear eye protection wheninstalling spring to preventinjury

With screwdriver positioned as shown, pressspring into place.

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3 Safety EquipmentInstall cover plate and secure with (4) screws.

Position hand guard on clutch cover. Presspivot sleeve halves into place.

Install and tighten screw. Disengage chain

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Safety Equipment 3Install bar, chain and clutch cover on saw. Testchain brake for proper operation.

Inertia Chain Brake Engagement

Hold the saw approximately 35 cm (14”) abovea stump or other firm object. Release grip onfront handle and allow front of saw to drop.When the bar tip hits the object, the chainbrake should activate.

Manual Chain Brake Engagement

Place the saw on firm ground and start theengine. While holding the saw with both hands,apply full throttle. Activate chain brake by turn-ing left wrist against hand guard as shown.Chain should stop immediately.

- WARNING -Avoid contact between anyobject and the guide bar tip.Contact can cause the chain and guide bar tosuddenly move upward and backward towardthe user. Use both hands on the handles.Follow all safety precautions in the operator’smanual. Failure to follow instructions couldresult in serious personal injury.

9



3 Safety Equipment

Throttle Trigger Lockout

Disassembly

Press out pin and remove throttle lockout.

Assembly

Install throttle lockout and secure with pin.

Chain Catcher

Inspect chain catcher. If damage is evident,remove screw and replace chain catcher.

10



Starter 4Disassembly

Remove screws (4) and starter assembly.

Pull starter cord out approximately 30 cm (1 2“)and position in starter pulley recess. Carefullyallow pulley to rotate counterclockwise untilspring tension has been relieved.

Remove screws (4) from guard ring.

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Starter

- WARNING -Wear eye protection whenremoving spring to preventinjury

Remove center post screw and washer.Carefully withdraw starter pulley.

- WARNING –Wear eye protection whenremoving spring to preventinjury

Position starter so spring side is toward bench.Tap housing down on bench sharply to removerecoil spring.

Clean all starter parts and check for wear ordamage.

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Starter 4Assembly

- WARNING -Wear eye protection wheninstalling spring to preventinjury

Insert hook on outer end of recoil spring intostarter housing as shown. Using thumbs, care-fully install new recoil spring into place.

Install starter cord into pulley as shown. Meltcord end to seal knot. If knot is too large it mayinterfere with starter pawls.

Thread starter cord through retaining rinq andeyelet as shown. Attach starter handle to rope.

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4 StarterApply a light coating of oil to starter pulley postand recoil spring.

Position starter pulley on starter housing asshown. Rotate pulley to engage recoil spring inpulley.

IMPORTANT: Starter pulley must be flushagainst recoil spring.

Secure starter pulley with washer and screw.Install guard ring with screws. Pull starter han-dle out and stop starter pulley with thumb. Liftcord into pulley recess, then preload spring byturning pulley three turns clockwise.

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Starter 4Pull starter cord all the way out. Make sure (starter pulley can be turned at least 1/2 turn,before the recoil spring fully tightens.

With starter handle extended approximately 30cm (1 2“) from housing, position starter againstsaw. Release starter handle to allow the pulleyto fit within the starter pawls on flywheel.Secure starter with screws.

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5 Ignition System

DescriptionModels 42, 42D and 242 are equipped with anelectronic ignition system. The spark generatedby this system has a higher energy and ashorter burning time than the spark generatedby a breaker point ignition. Because of this, thespark, across the spark plug electrode,appears to be weaker.

0.5mm (.020”)

Checking the Spark

Remove and clean spark plug. Check sparkplug electrode gap.

Spark plug gap should be 0.5 mm (.020”). Ifelectrodes are worn, spark plug must bereplaced.

With ON/OFF switch in “ON” position, groundspark plug to cylinder and pull starter handle. Aspark should appear across the electrodes.

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IgnitionSvstem 5If no spark appears, install new spark plug ortest plug P/N 50271 13-01 and pull starterhandle.

If no spark appears, remove ON/OFF switchlead from stop switch and pull starter handle,spark appears, stop switch is faulty and muslbe replaced. If no spark appears, check hightension leads, connections and contacts fordirt, wear and/or damage.

If

Using air gap gauge P/N 5025134-02 checkair gap between flywheel magnet and ignitionmodule. Air gap should be 0.3 mm (.012”).

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5 Ignition System

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If replacing ignition module does not restorespark, replace coil.

Replacement of the Ignition Module

Remove leads from ignition module. Removescrews and ignition module. Position new igni-tion module as shown and install but do nottighten screws.



Ignition System 5Place air gap gauge P/N 5025134-02between ignition module and flywheel. Pressignition module against air gap gauge. Makesure flywheel magnets are in line with moduleand tighten ignition module screws. Remove airgap gauge.

Connect blue ON/OFF switch lead (1) and redcoil lead (2) to ignition module. Be sure to routeall leads away from flywheel.

Replacement of the Coil

Remove high tension lead from spark plug.Remove ignition module lead and screws.Remove coil. Position new coil as shown andsecure with screws. Connect ignition modulelead to coil.

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5 Ignition System

Using assembling pliers P/N 5025006-01,make a guide hole in high tension lead.

Insert ignition lead through rubber cover andinstall contact spring in guide hole and securewith assembling pliers. Slide rubber cover overcontact spring.

Removal of the Flywheel

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Remove spark plug and thread piston stop P/N5025033-01 into spark plug hole until tight.



Ignition System 5Remove flywheel nut and washer (1).starter pawls (2).

Remove

Remove piston stop P/N 5025033-01. Installflywheel removal tool P/N 5025149-01 to theflywheel with the M5 screws. Ensure pullerP/N 5025026-01 is centered, then tightenpuller screw and lightly tap puller, and removeflywheel.

On G series saws (models with heated han-dles) the generator is now visible and can beremoved. The sealing ring holder is locatedbehind the generator.

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5 Ignition SystemRemove flywheel removal tool from flywheel.Inspect starter pawls for damage or wear.Check pawl return spring tension. Replaceparts as necessary.

Installation

Install flywheel key in crankshaft keyway andinstall flywheel.

Thread piston stop into spark plug hole untiltight. Install flywheel washer and nut. Torqueflywheel nut to 24-29 Nm. (17 -21 ft. Ibs.)Install starter pawls. Remove piston stop.

IMPORTANT: Starter pawls must movefreely.

22



Heated Handles 6Identification

The symbol “G” means the saw is equippedwith electrically heated front and rear handles.The required electric power is produced by agenerator located behind the flywheel. Thissystem requires no maintenance and is con-trolled by an ON/OFF switch on the right sideof the saw.

Checking the Switch

Remove lead from switch. Connect ohmmeterto crankcase (1) and lead connector (2). Slideswitch to “ON” and then “OFF” position. Whenthe switch is in the “ON” position the needleshould move. When the switch is in the “OFF”position the needle should show no movement.

Handle Element

Oxidation of lead connections and rear socketare common causes of element failure. Cleanelements as needed.

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6 Heated Handles

Checking the Rear Handle Element

With heater switch in the ‘(OFF” position, testthe two heating elements in the rear handlebetween points 2 and 3. The meter should read1.4 -1.8 ohms. Connect meter between points4 and 2 and then between 4 and 3. The metershould read 0.7 -0.9 ohms in both positions.

Checking the Front Handle Element

With heater switch in the “OFF” position, testbetween points 1 and 3. Meter should read 3.7-3.9 ohms. If the reading is below 3.7 ohms,the entire front handle must be replaced.

Checking the Complete HeatingSystem

Test both rear and front handles as follows.With heater switch in the “OFF” position, con-nect meter between points 1 and 2. Metershould read 5.1 -5.7 ohms.

Checking the Generator

– WARNING -Never start chain saw withoutbar chain and clutch coverinstalled. The clutch couldcome loose and cause severeinjury

A voltmeter capable of reading AC voltage isneeded to test generator.

Start saw and move heater switch to “ON” posi-tion. With saw running at 10000 rpm attachvoltmeter leads to point 1 and crankcase.Meter should read 20 volts at 10000 rpm. A lowreading can be caused by interruption in gener-ator windings, insufficient magnetization ordefective leads.

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Centrifugal Clutch 7Disassembly

Remove clutch cover, chain and bar. Removecylinder cover. Remove spark plug. Thread pis-ton stop P/N 5025033-01 into spark plug holeuntil tight.

Loosen the clutch, turn wrench in direction ofarrow (clutch has left hand threads).

Remove clutch drum. On 242 models, removerim sprocket.

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Centrifugal Clutch

Dismantle the clutch spring. Use a pair of pliersP/N 5025049-01 and a small screwdriver.

and poor function.

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Centrifugal Clutch 7Check chain sprocket and clutch drum for wearor damage. Replace as necessary.

Assembly

Put the spring in one of the clutch shoes sothat the spring end loop lies in the middle of theshoe and mount it to the hub. Place an addi-tional clutch shoe on the hub.

Fit the remaining clutch shoe. Use a pair ofpliers, P/N 5025049-01 and a screwdriver.

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Centrifugal Clutch

On 242 models, install rim sprocket on clutchdrum.

Install clutch drum on crankshaft. Thread clutchcounterclockwise onto crankshaft. Clutchassembly must be secure on crankshaft. Applygrease to needle bearing through hole incrankshaft. Remove piston stop. Install sparkplug and cylinder cover. Install bar, chain andclutch cover.

- WARNING -Never start chain saw withoutbar chain and clutch coverinstalled. The clutch couldcome loose and cause severeinjury

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Chain Lubrication System

Disassembly

Remove oil tankerly and flush OutI

filler cap. Dispose of oil prop-oil tank with solvent. Remove

debris from tank using low pressure air.Remove clutch cover, chain, bar and clutchassembly. Remove three screws from oil pump.

Thread two M5 screws into pump housing asshown. Tighten screws alternately half a turneach time until pump housing comes loose.Remove pump housing and M5 screws.

Note: Removal of the oiler also removesdust cover washer on the crankshaft.

the

Lift oil suction hose and filter from oil tank andclean or replace oil pick-up filter.



8 Chain Lubrication System

Screw oil gear puller P/N 5053818-17 com-pletely onto worm gear clockwise. Screw pullerbolt into sleeve and remove worm gear fromcrankshaft.

Tap pump housing against sturdy surface toremove sealing plug and pump piston.

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Chain Lubrication System 8Assembly

.Lubricate pump parts with chain oil. Pushpump piston to bottom of housing. Install andseat adjusting screw (1). Back adjustmentscrew out 1-1/2 turns for initial adjustment.

Make sure locking tabs fit in groove of adjustingscrew. Tighten lock screw (2). Press in sealingplug (3) and install rubber output sleeve (4).

Thread worm gear into puller sleeve until flushwith end of sleeve. Place sleeve with gear overthe end of the crankshaft. Tap sleeve down witha plastic hammer until gear contacts the shoul-der on the crankshaft.

Place suction hose with filter in oil tankopening.

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8 Chain Lubrication System

Coat worm gear and oiler drive gear with lightpetroleum grease.

Install oil pump and secure with screws. Installwasher with labyrinth seaI against pump. Usinga seal driver securely seat the washer.

Install clutch assembly, bar, chain and guidebar cover.

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Anti-Vibration System 9System DescriptionThe powerhead, bar and chain are isolatedfrom the front and rear handles by four shockmounts. These shock mounts are designed toreduce the vibration at the operator’s handswhich is generated by the powerhead and thecutting equipment.

Replacement of the Shock Mounts

Empty fuel tank. Remove clutch cover, chain,bar, cylinder cover, air filter and starterassembly.

Disconnect fuel hose. On “G” models, discon-nect leads from generator to handles at con-nectors. Remove four shock mount screws.Separate fuel tank assembly and front handlefrom powerhead.

Remove the four shock mounts using 11 mmspanner P/N 5025067-01. Install and securenew shock mounts with 11 mm spanner.

IMPORTANT: All 4 shock mounts must bereplaced as a set.

Position remaining two shock mounts andreassemble saw.

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10 Fuel System

Checking the Fuel Tank Ventilation

Empty fuel from tank into a suitable container.Remove cylinder cover. Remove fuel hose fromcarburetor. Install and tighten fuel tank cap.Connect pressure gauge P/N 5025038-01 tofuel hose. Pump gauge to 50 kPa (7 psi).Pressure should drop to 20 kPa (2 psi) within60 seconds.

NOTE: Rate at which pressure drops can varydepending on type of two stroke oil used infuel.

Replacement of the Vent

Remove fuel tank cap completely. Using acurved needle nose pliers, grip vent tube andpush vent out through passage.

Using a suitable punch, push new fuel tankvent into place. Some vents are threaded andrequire a screwdriver.



Fuel System 10

Carburetor

- WARNING -Never start chain saw withoutbar, chain and clutch coverinstalled. The clutch couldcome loose and cause severeinjury.

Adjustment

Clean air filter and fuel filter before adjustingcarburetor.

There are three adjustment screws on thecarburetor:

L =H =T =

Low speed screwHigh speed screwIdle speed screw

Turn screws L and H clockwise until lightlyseated. Turn screw L counterclockwise 1-1/2turns. Turn screw H counterclockwise 1-1/4turns.

, . , , , _ , . # . . . . e

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10 Fuel System

2,500-2,800rpm

Start saw and allow to warm up. Adjust screw Tuntil saw idles between 2500-2800 rpm or justbelow clutch engagement.

Turn screw L clockwise just until engine rpmdecreases (lean drop). Note this position, thenturn screw L counterclockwise until engine rpmdecreases (rich drop) and note this position.Set screw L between lean and rich positions.Make sure engine does not hesitate on accel-eration and saw chain doesn’t rotate at idle.

Adjust screw H for optimum cutting perfor-mance under load. Using a tachometer, ensuremaximum no load rpm does not exceed 14000for 42, 42D models and 15500 for 242 models.

caution: Do not adjust carburetor less than7/8 turn open on (H) needle, this can cause anover speeding condition and possible lack oflubrication.

Removal of Carburetor

Remove cylinder cover. Remove air filter.Disconnect choke linkage. Remove fuel hoseand, if equipped, heated handle switch lead.

Remove (2) screws. Lift and turn carburetor todisconnect throttle linkage.

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Fuel System 10Remove screw (1), washer (2), filter holder (3),gasket (4), manifold (5), gasket (6) and screw-driver guide (7) from carburetor.

Metering Side

Disassembly

Remove screws (1). Remove meteringdiaphragm cover (2) and meteringdiaphragm (3).

Connect pressure gauge P/N 5025038-01 tofuel hose nipple and submerge carburetor in acontainer of non-flammable clear solvent. Testpressure atpermitted.

50 kPa (7 psi). No leakage

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10 Fuel System

n

If leakage occurs, loosen screw and removeneedle valve.

Inspect needle valve (1) and leveror damage. Replace if necessary.

(2) for wear

Check shafts (1), choke and throttle plates (2),springs (3) and fast idle levers (4) for wear ordamage. Replace if necessary.



Fuel System 10Fuel Pump

Disassembly

Remove screw (l). Remove fuel pump cover(2), gasket (3) and diaphragm (4).

NOTE: The internal passages of the carbure-tor body are delicate and are easily damaged ifproper service procedures are not used.Damage to the fuel passages and seats is notrepairable and will necessitate the installationof a new carburetor. Make sure the work areais clean and exercise extreme care duringdisassembly, cleaning and reassembly of thecarburetor.

Drill a small hole in welch plug (1) and cup plug(2). Place a screwdriver in hole and pry outplugs. Remove fuel screen (3). Remove adjust-ing needles and springs (4). Clean carburetorhousing and parts in suitable solvent and drywith low pressure air.—

Assembly

Install new fuel screen (3). Tap new welch plug(1) and cup plug (2) into place. Seal plugs withnail polish. Install springs and adjustingneedles (4).

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10 Fuel System

Install choke (1) and throttle (2) assemblies.Install needle valve (3), spring (4), lever (5) andpin (6). Secure with screw (7).

Metering lever must be level with meteringdiaphragm mounting area of carburetor. Adjustif necessary.

Install metering diaphragm and gasket. (Besure diaphragm is captured on needle lever.)Install metering diaphragm cover with ventila-tion hole facing cylinder. Secure with screws.



Fuel System 10Replace fuel inlet screen (1). Assemble fuelpump diaphragm, gasket and cover as shownand secure with screw (2).

Be sure fuel inlet fitting is angled correctly.Pressure test carburetor as outlined earlier inthis section. No leakage is allowed.

Inspect manifold for damage and make sureimpulse channel is open. Replace if necessary.

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10 Fuel System

Assemble screws and washers (1), filter holder(2), carburetor (3), gasket (4), manifold (5),gasket (6) and screwdriver guide (7).

Installation of Carburetor

Connect throttle linkage to carburetor. Positioncarburetor as shown and tighten screws (1). Besure fuel hose (2) is at least 95 mm (3-3/4 in.)above fuel tank and connect choke linkage (3)and, as equipped, heat switch lead (4). Installair filter and cylinder cover.

42



Fuel System 10Disassembly

Remove cylinder cover and air filter.

On Model 42D the compression release valvelocated on the clutch (right) side of the cylindercan be removed for inspection or replaced ifnecessary by using a 13 mm socket.

Disconnect choke linkage (1), fuel hose andstop switch wire (2). Remove spark plug lead(3) from spark plug. Remove spark plug.

Remove screw securing muffler to front ofcrankcase. Remove (4) cylinder screws. Liftcylinder assembly, carburetor and muffler fromsaw.

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Cylinder and Piston

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Remove carburetor and muffler. Clean exhaustport. Check spark screen, clean or replace.

Place piston ring in cylinder approximately 1/2way down and check ring gap.

NOTE: Proper ring gap is 0.25-0.30 mm(0.010” - 0.012”), max 1.0 mm (0.040).



Cvlinder and Piston

Assembly

NOTE: Replace all gaskets when reassem-bling piston/cylinder.

Position piston on connecting rod with arrow onpiston top facing the exhaust side as shown.Apply a few drops of oil to wrist pin, Push wristpin into place. Secure wrist pin with new cir-clips. Openings in circlips should be at either12 o’clock or 6 o’clock.

Install new cylinder base gasket.

Secure muffler and carburetor to cylinder afterreplacing gaskets.

Apply oil to piston. Install piston ring with open-ing at piston pin. Install piston ring compressorP/N 5025070-01 on piston as shown.

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46

Lower cylinder down onto piston. Gently pushcylinder down until ring has entered the cylin-der. Remove piston ring compressor.

Secure cylinder with screws. (Be sure cylindergasket is aligned properly before installingcylinder.) Secure muffler support to crankcasewith screw. Install spark plug and spark pluglead. Connect choke linkage, fuel hose andstop switch wire.

Install air filter and cylinder cover.



Cylinder and Piston 1 1

Changing a Bar Stud

Empty and rinse out the oil tank. Using a driftpunch, tap the bar stud into the oil tank. Extractthe stud through the oil filler opening. Insert asmaller diameter wire through the bar stud holein the crankcase and out the oil filler opening.Wrap the end of the wire around the bar studthreads, then guide the stud through the oiltank and stud hole. Remove the wire. Place asleeve or washers over the stud. Thread a studnut down onto the stud to pull the stud into itsseat.

Changing the Crankshaft Seals

The crankshaft seals are accessible afterremoving:

● The flywheel and, if equipped, the heatedhandle generator as instructed in Section 6.

● Ignition Systems and the oil pump asinstructed in Section 5.

● Chain Lubrication Systems in Section 8.

The seals can be pried out using a suitablescrewdriver. Be careful not to scratch or dam-age the crankshaft during seal removal.

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12 Crankcase and Crankshaft

Crankcase

Disassembly

Remove the oil pump (see Section 8), flywheel(see Section 5), piston and cylinder (seeSection 11). Remove the four rubber elementsand separate the crankcase from the tank.

Remove the seven screws retaining the

Mount tool P/N 5025161-01 on the clutch side— of the crankshaft and crankcase. Separate the

crankcase halves by pressing the crankshaftout of the right crankcase half.

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Crankcase and Crankshaft 12Mount the tool on the left crankcase half andpress out the crankshaft.

Remove the crankshaft bearings from thecrankcase halves by heating up the crankcasearound the crankshaft bearing then pressingthe bearing out of the case.

Checking the Crankshaft

The crankshaft is not serviceable and must beexchanged if defective. Some crankshafts mayhave a slight blue discoloration around thecrank pin. This is a normal condition caused bythe heat treatment around the crank pin holeduring assembly.

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Very carefully inspect the connecting rod big-end (crank pin) bearing. Hold the connectingrod flush against one crank half and then theother while rotating the rod around the pin.Look for cracks or other damage to the bearingcage. Examine the connecting rod big-end forseizure marks on the sides or discoloration.

Check for radial movement (up and down play)of the connecting rod. Replace the crankshaft ifradial movement is detected. Slight axial move-ment (side to side) is acceptable.

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Check the small-end of the connecting rod. Ifseizure marks or discolored spots are evidentin the bearing seat, the crankshaft must bereplaced.



Crankcase and Crankshaft 12Assembly

Thoroughly clean all parts before assembly.Make sure the crankcase half mating surfacesare clean and free of all gasket material. Heatthe bearing seat area of the ignition (left) sidecrankcase half and install the crankshaft bear-ing. Make sure the bearing is fully seated.

Heat the bearing seat area of the drive (right)side crankcase half and install the crankshaftbearing ensuring it is fully seated.

Using assembly tool P/N 5025030-07 pull thecrankshaft into the ignition side crankcase half(left). Make sure the crankshaft is flush againstthe bearing.

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52

Position the crankcase gasket onto the ignitionside crankcase half using a light coating ofgrease to hold it in place.

NOTE: The crankcase alignment pins shouldbe located in the ignition side crankcase half.

Slide the drive side crankcase half (right) ontothe crankshaft, then mount the assembly tool.Pull the crankshaft into the crankcase halfwhile guiding the two halves together. If neces-sary, start a few crankcase screws to hold thegasket in place. Make sure the crankshaft isflush against the bearing, then remove theassembly tool.

Install ail the crankcase screws except the topfront screw which also retains the bar spikeand muffler support. Starting with the screwsaround the crankshaft, tighten all six screws to7-9 Nm (5.1 -6.6 ft. Ibs.) torque.



Crankcase and Crankshaft 12Always use new crankshaft seals. Begin withthe ignition side. Apply grease to the crankshaftseal lip and carefully slide the seal over the endof the crankshaft. The open side of the sealmust face inward. Drive the seal into thecrankcase using tool P/N 5025082-01 untilthe seal is flush with the crankcase. Install thedrive side crankshaft seal in the same manner.

The remainder of reassembly of the unit is thereverse of disassembly. Refer to the appropri-ate sections for reassembly instructions.

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NOTESFor Husqvarna Parts Call 606-678-9623 or 606-561-4983


Documents

Workshop Manual, 42/42D/242, 1995-01, Chain Saw...42, 42D, 242 Workshop Manual 531 03 01-21 For Husqvarna Parts Call 606-678-9623 or 606-561-4983 Introduction The procedures included