Stihl MS 231 Manual Download Page 107

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106

MS 231, MS 231 C, MS 251, MS 251 C

Remove the fuel suction
hose (1),

12.11.2

Disconnect the fuel suction
hose (1) and fuel return hose (2)
from the nipples (arrows).

Installing

Install the fuel suction hose (1),

12.11.2

2310RA395 TG

2310RA396 TG

2310RA397 TG

– Use STIHL press fluid to simplify

assembly,

Fit the grommet (1) in the
hole (arrow) in the fuel tank and
make sure it is properly seated.

Push the connector (1) into the
fuel return hose (2) as far as stop.

Machines with QuickStop Super

Pass the fuel return hose (1),
connector first, under the brake
cable (2).

2310RA398 TG

2310RA399 TG

2310RA400 TG

Fit the connector (3) with fuel
return hose (1) between the
ribs (arrows) and push it into the
grommet (4).

The fuel return hose (1) must be
under the brake cable (2) and run to
the left as shown in the illustration.

Pass the fuel return hose (1)
upwards through the
opening (arrow) in the engine
housing.

Install the fuel hose (1),

12.11.2

2310RA401 TG

2310RA402 TG

2310RA403 TG

All manuals and user guides at all-guides.com

Summary of Contents for MS 231

Page 1: ...STIH STIHL MS 231 251 2010 10 All manuals and user guides at all guides com a l l g u i d e s c o m ...

Page 2: ... Timing 45 7 2 Preseparator 45 7 3 Install new ignition module 45 7 4 Testing the Ignition Module 47 7 5 Spark Plug Boot Ignition Lead 48 7 6 Flywheel 49 7 7 Short Circuit Wire 50 7 7 1 Testing 50 7 7 2 Removing and Installing 50 7 7 3 Ground Wire 53 7 7 4 Contact Spring 53 7 8 Ignition System Troubleshooting 55 8 Rewind Starter 58 8 1 General 58 8 2 Fan housing 58 8 3 Pawls 59 8 4 ErgoStart 60 8 ...

Page 3: ...or 95 12 7 1 Basic Setting 95 12 7 2 Standard setting 96 12 8 Carburetor Carrier 97 12 9 Intake Manifold 98 12 10 Tank Vent 99 12 10 1 Testing 99 12 10 2 Removing and Installing 100 12 11 Fuel Intake 101 12 11 1 Pickup Body 101 12 11 2 Fuel Hose 101 12 11 3 Fuel Hoses Manual Fuel Pump 105 12 11 4 Manual Fuel Pump 107 12 11 5 Tank Housing 108 13 Special Servicing Tools 110 14 Servicing Aids 112 All...

Page 4: ...ols manual The manual lists all special servicing tools currently available from STIHL Symbols are included in the text and pictures for greater clarity The meanings are as follows In the descriptions Action to be taken as shown in the illustration above the text Action to be taken that is not shown in the illustration above the text In the illustrations A Pointer a Direction of movement 4 2 Refer...

Page 5: ...ays wear suitable protective gloves for operations in which components are heated for assembly or disassembly Improper handling may result in burns or other serious injuries Always replace damaged parts Check disassembled parts for wear or damage before re installing replace as necessary Run the machine only with the shroud mounted in position there is otherwise a risk of injury from the fanwheel ...

Page 6: ...tch without linings Clutch engages at 3 500 rpm 3 500 rpm Crankcase leakage test at gauge pressure 0 5 bar under vacuum 0 5 bar 2 2 Fuel System Carburetor leakage test at gauge pressure 0 8 bar Operation of tank vent at gauge pressure 0 5 bar Fuel as specified in instruction manual 2 3 Ignition System Air gap between ignition module and fanwheel 0 30 0 05 0 10 mm Spark plug resistor type NGK CMR 6...

Page 7: ...lar screw D 8x18 Collar stud for bar 16 0 Collar screw D 8x18 Collar stud for bar 16 0 B Collar screw D 9x18 Collar stud for bar engine housing repair solution 16 0 Screw P 5x18 Cover chain brake engine housing 4 0 Nut M 5 Filter base baffle carburetor 3 5 Screw P 6x26 5 Handlebar tank housing right 6 0 Screw M 5x16 Handlebar tank housing bottom 5 0 2 3 Screw M 5x20 Hand guard fan housing engine h...

Page 8: ...r Use the following procedure when refitting a DG or P screw in an existing thread Place the screw in the hole and rotate it counterclockwise until it drops down slightly Tighten the screw clockwise to the specified torque This procedure ensures that the screw engages properly in the existing thread and does not form a new thread and weaken the assembly Coat micro encapsulated screws with medium s...

Page 9: ...ed Engine idle speed too high Readjust idle speed screw LA Clutch springs stretched Replace the clutch springs or install new clutch Clutch springs broken Replace the clutch springs Loud noises Clutch springs stretched Replace all clutch springs Needle cage damaged Fit new needle cage Clutch shoe retainer broken Install new retainer or clutch Clutch shoes and carrier worn Install new clutch All ma...

Page 10: ...rum badly worn Install new clutch drum Brake band blocked Check freedom of movement and operation of brake band Saw chain rotates at idle speed Engine idle speed too high Readjust idle speed screw LA Clutch springs stretched Replace the clutch springs or install new clutch Clutch springs broken Replace the clutch springs Saw chain does not stop immediately when brake is activated Brake spring stre...

Page 11: ...nnected or broken Reconnect or replace brake cable QuickStop Super Coasting brake does not disengage properly even though lockout lever is depressed Too much free travel on lockout lever Adjust brake cable QuickStop Super Braking action of coasting brake inadequate lockout lever not depressed Brake cable overtensioned Adjust brake cable All manuals and user guides at all guides com a l l g u i d e...

Page 12: ...ntake hose ruptured Fit new intake hose and pickup body Valve in oil tank blocked Clean or replace valve Teeth on worm worn Install new worm Oil pump damaged or worn Install new oil pump Machine losing chain oil Oil pump damaged or worn Install new oil pump Oil suction hose connection damaged Install new oil intake hose Engine housing cracked Install new engine housing Oil pump delivers insufficie...

Page 13: ...tarter rope can be pulled out almost without resistance crankshaft does not turn Guide peg on pawl or pawl itself is worn Fit new pawl Spring clip on pawl fatigued Fit new spring clip Spring clip installed wrong Install spring clip correctly Models with ErgoStart Guide pegs on pawls or pawls themselves are worn Fit new pawls Torsion springs on flywheel fatigued pawls worn or sticking Clean seats o...

Page 14: ...emperatures Lubricating oil on rewind spring becomes viscous spring windings stick together or moisture has got onto the rewind spring spring windings frozen together Coat rewind spring with a small amount of standard solvent based degreasant containing no chlorinated or halogenated hydrocarbons then pull rope carefully several times until normal action is restored All manuals and user guides at a...

Page 15: ... gap between ignition module and flywheel Set air gap correctly Flywheel cracked or damaged or pole shoes have turned blue Install new flywheel Ignition timing wrong flywheel out of adjustment key in flywheel has sheared off Install new flywheel Weak magnetization in flywheel Install new flywheel Irregular spark Check operation of switch shaft contact spring and ignition module Damaged insulation ...

Page 16: ... a new metering diaphragm Metered diaphragm deformed Fit a new metering diaphragm Poor acceleration Setting of low speed screw too lean Check basic carburetor setting correct if necessary Setting of high speed screw too lean Check basic carburetor setting correct if necessary Inlet needle sticking to valve seat Remove inlet needle clean and refit Diaphragm gasket leaking Fit new diaphragm gasket M...

Page 17: ...w speed screw too rich or too lean Reset low speed screw L correctly Setting of idle speed screw LA incorrect throttle shutter completely closed Reset idle speed screw LA correctly Tank vent faulty Replace tank vent Leak on fuel hose from tank to carburetor Seal connections or install new fuel hose Saw chain rotates at idle speed Engine idle speed too high Readjust with idle speed screw LA counter...

Page 18: ...l hose from tank to carburetor Seal connections or install new fuel hose Setting of high speed screw H too rich Check basic carburetor setting correct if necessary Main jet bores or ports blocked Clean the carburetor Pump diaphragm damaged or fatigued Fit new pump diaphragm Ignition timing wrong flywheel out of adjustment key in flywheel has sheared off Install new flywheel Engine running extremel...

Page 19: ...gine does not deliver full power or runs erratically Piston rings worn or broken Fit new piston rings Muffler spark arresting screen carbonized Clean the muffler inlet and exhaust replace spark arresting screen replace muffler if necessary Air filter dirty Clean or replace air filter Fuel hose kinked or torn Fit new hose or position it free from kinks Intake manifold damaged bore blocked Clean bor...

Page 20: ...nscrew the spark plug Hold the locking strip 1 0000 893 5904 so that the flat side of its metal top faces the piston and then push it into the cylinder The locking strip 1 0000 893 5904 must butt against the cylinder wall arrow and the flat side of its metal top must rest on the piston crown as shown in the illustration 2310RA001 TG 1 2310RA002 TG 1 2310RA003 TG 1 Apply wrench to hexagon arrow and...

Page 21: ... must rotate freely when the lockout lever is depressed With the coasting brake disengaged open the throttle wide and let go of the lockout lever on the rear handle the chain must come to an abrupt stop All models The braking time is in order if deceleration of the saw chain less than a second is imperceptible to the eye If the chain brake does not operate properly refer to troubleshooting b 3 2 5...

Page 22: ...er 1 in the slots arrows first Place the cover 1 in position Insert and tighten down the screws 2 firmly 1 2310RA012 TG 2 2310RA013 TG 1 TOP 2310RA014 TG 2 2 1 Install the clutch drum b 4 1 The clutch drum must rotate freely when the chain brake is disengaged Carry out the other checks b 5 1 Reassemble all other parts in the reverse sequence 5 3 Brake Lever Troubleshooting b 3 2 Remove the shroud ...

Page 23: ...d replace the hand guard if necessary Installing Clean the pivot pins and disassembled parts b 14 Lubricate the pivot pins b 14 Push the loop of the flat spring 1 into its seat arrow as far as stop 2310RA019 TG 2 1 TOP 2310RA020 TG 1 Fit the strap 1 on the pivot pins 2 and 3 so that TOP faces outwards and the curve arrow faces up Slip the spacer washer 1 onto the pin 2 Hold the brake lever 2 so th...

Page 24: ...rake lever on to the pivot pins Fit the retaining ring 1 The turns of the brake spring must be tightly against one another in the relaxed condition If this is not the case replace the brake spring If the groove in the brake spring s anchor pin is worn install a new engine housing b 6 6 2310RA027 TG 1 2310RA028 TG Hook the brake spring 1 to the brake lever arrow Use the assembly tool 2 1117 890 090...

Page 25: ...310RA032 TG 1 Pull the hand guard 1 and brake lever 2 off the pivot pins arrows together Remove the hand guard and brake lever Disconnect the brake cable 1 Remove the spacer washer 1 and strap 2 Pull out the flat spring 3 TOP 2310RA033 TG 1 2 2310RA034 TG 1 2310RA018 TG 1 2 3 Take the brake lever 2 out of the hand guard 1 Check the anchor pin if it is worn install a new engine housing Check the ca...

Page 26: ...arrow Push the hand guard 1 with brake lever 2 over the machine until they are positioned against the pivot pins arrows 2310RA037 TG 1 2310RA038 TG 2 1 Lift the bearing boss of the hand guard 1 and the brake lever 2 a little and position them over the pivot pins arrows Push the flat spring 1 slightly to one side until the cam of the hand guard arrow slips passed it Push the hand guard bearing boss...

Page 27: ...e sequence 5 4 1 Adjusting the brake cable If problems occur on the coasting brake even though the brake band is in order the reason may be the adjustment of the brake cable Troubleshooting b 3 2 Checking condition and free travel Remove the chain brake cover b 5 2 The brake cable must be relaxed when the lockout lever is released TOP 2310RA031 TG 1 Press down the lockout lever 1 and hold it in th...

Page 28: ... position The brake band 1 must locate snugly against engine housing arrows and the clutch drum must rotate freely Reassemble all other parts in the reverse sequence 5 4 2 Brake cable Removing and Installing Disconnect the brake spring b 5 4 Remove the carburetor b 12 5 Remove the throttle trigger b 10 3 Remove the switch lever b 10 3 1 TOP 2310RA044 TG 1 Pull out the brake cable 1 a little and di...

Page 29: ...s hexagon and the retainer is 2 mm Fit the clamp screw 2 and tighten it down firmly Pass the brake cable 1 between the tank housing and engine housing to the right of the fuel hose 3 or on versions with a manual fuel pump to the right of the fuel hose 3 and fuel return hose 2 Push the brake cable 1 short hook 4 first through the bore arrow in the engine housing 2310RA056 TG 1 2 3 1 4 2310RA058 TG ...

Page 30: ...sary b 12 11 2 Check position of fuel return hose and correct if necessary b 12 11 3 Lift the tank housing and secure it in position b 12 11 2 Position the brake cable 1 in the guide arrow Install the switch lever b 10 3 1 Install the throttle trigger b 10 3 1 2310RA060 TG 2 1 2310RA063 TG Reassemble all other parts in the reverse sequence Check operation and adjust the brake cable b 5 4 1 5 5 Cha...

Page 31: ...thin side first see arrow into the opening and press it down until it snaps into position Take out the screw arrow Remove the cover plate 1 and adjusting wheel 2 When installing the adjusting wheel make sure its teeth face the cover plate Reassemble in the reverse sequence 1 165RA007 TG 2310RA045 TG 1 2 5 5 2 Chain Catcher Remove the chain sprocket cover The chain catcher arrow is an integral part...

Page 32: ...is badly damaged or stripped it will not be possible to tighten the standard collar stud to the specified torque the security of the collar stud is no longer guaranteed In such a case use the collar stud in the screw list as a repair solution b 2 5 Remove the standard collar stud do not re drill the hole Coat the thread of the collar stud 1 with threadlocking adhesive b 14 Fit the collar stud by h...

Page 33: ...g screen if fitted see instruction manual Installing Cover the exhaust port Remove any dirt from around the cylinder and exhaust port Check and clean the sealing faces arrows remove any gasket residue make sure there is no gasket residue or dirt in the exhaust port Always replace components with damaged sealing faces Position the new exhaust gasket 1 so that the tabs arrows point towards the cylin...

Page 34: ...off the boot and unscrew the spark plug Set the piston to top dead center This can be checked through the spark plug hole 2310RA079 TG 1 Fit the spark plug 1 and tighten it down firmly Remove the muffler and gasket b 6 1 Fit the test flange 1 5910 855 4201 on cylinder exhaust port Fit the screws 2 do not tighten down yet Flange 1 4224 893 2501 can be modified as shown a 13 mm b 39 25 mm c 6 mm 2 2...

Page 35: ...e oil seals must be replaced b 6 3 After finishing the test push the ring to the right to vent the pump Continue with pressure test b 6 2 3 6 2 3 Pressure Test Carry out the same preparations as for the vacuum test b 6 2 2 Push ring 1 to the right pressure test Operate the lever 2 until the pressure gauge 3 indicates a pressure of 0 5 bar If this pressure remains constant for at least 20 seconds t...

Page 36: ...g b 8 2 Remove the flywheel b 7 6 Take care not to damage the crankshaft stub Free off the oil seal in its seat by tapping it with a suitable tube or a punch Apply puller 1 5910 890 4400 Clamp the puller arms Pull out the oil seal Installing Clean the sealing face b 14 Lubricate sealing lips of new oil seal with grease b 14 2310RA080 TG 1 Fit the installing sleeve 1 1141 893 4600 Slip the oil seal...

Page 37: ...lips of new oil seal with grease b 14 Fit the installing sleeve 1 1118 893 4602 Slip the oil seal open side facing the engine housing over the installing sleeve Remove the installing sleeve 1 Fit press sleeve 1 1122 893 2405 with the collar arrow facing the engine Use press sleeve 1 1122 893 2405 to install the oil seal 2 The seating face must be flat and free from burrs 2310RA085 TG 1 2310RA086 T...

Page 38: ...part concerned b 3 7 Remove the shroud b 6 4 Pull off the boot and unscrew the spark plug b 4 Remove the fan housing b 8 2 Remove the flywheel b 7 6 Remove the clutch b 4 Remove the oil pump b 11 3 Remove the filter base b 12 3 Remove the carburetor b 12 5 Remove the carburetor carrier b 12 8 Remove the air guide shroud b 12 4 2310RA091 TG Remove the muffler b 6 1 Remove the handlebar b 9 4 Remove...

Page 39: ...t crankshaft stub 1 in the opening arrow in the engine housing Carefully position the engine in the engine housing support the engine pan from below with one hand Line up and hold the engine in the engine housing the bores in the engine housing engine pan and cylinder must be in alignment Insert the screws 1 do not tighten them down yet 2310RA096 TG 1 1 2310RA092 TG 1 1 1 Viewing the engine from a...

Page 40: ... clean all sealing faces b 14 When reinstalling the cylinder always seal it with fresh sealant on the engine pan Inspect the piston and piston rings and replace if necessary b 6 8 b 6 9 2310RA102 TG 2 2 1 2 2310RA103 TG 1 If the piston or the oil seals are damaged also inspect the inside of the cylinder for signs of damage and install a new cylinder if necessary Installing Fit the manifold 1 in po...

Page 41: ... top of the cylinder bore is tapered to ease installation When pushing the piston into the cylinder check that the gaps in the piston rings meet at the fixing pins they might otherwise break Position the piston 1 on the cylinder bore and ease it into the cylinder 2 2310RA107 TG 1 2 3 2310RA108 TG 1 2 Push the crankshaft 1 into the bearing seats arrows as far as stop Position the oil seals 2 so tha...

Page 42: ...n so that the sealant is evenly distributed Take care not to damage the crankshaft stubs Install the engine b 6 5 6 7 Bearings Crankshaft Remove the engine b 6 5 Remove the crankshaft and pull off the oil seals b 6 6 Remove the piston b 6 8 Pull out the needle cage 1 check it and replace if necessary 2710RA113 TG 1 Pull the ball bearing 1 off the tapered crankshaft stub ignition side Pull the ball...

Page 43: ...b 6 5 Install the engine b 6 5 6 8 Piston Remove the engine b 6 5 Remove the crankshaft b 6 6 The assembly drift passes through the installed snap ring Therefore only one snap ring needs to be removed Remove the snap at the side with the recess Use a suitable tool to grip the hookless snap ring at the recess arrow and ease it out 2710RA119 TG 1 2710RA418 TG Slide the assembly drift 1 1110 893 4700...

Page 44: ...93 1707 from the installing tool 2 5910 890 2210 Attach the snap ring 1 to the magnet 2 so that the snap ring gap is on the flat side of the tool s shank arrow Push the large slotted diameter of the sleeve over the magnet and snap ring The inner pin 1 must point towards the flat face of the tool s shank 2 5904RA089 TG 2 1 165RA153 TG 1 2 5904RA090 TG 2 1 Press the installing tool downwards into th...

Page 45: ...0RA420 TG 2310RA421 TG 6 9 Piston Rings Remove the piston b 6 8 Remove the piston rings from the piston Use a piece of old piston ring to scrape the grooves arrows clean Position the new piston rings so that the radii face upward arrows 5902RA160 TG 5902RA161 TG Carefully fit the piston rings over the piston they might otherwise break Install the piston rings so that the radii at the ring gap meet...

Page 46: ... be installed if no ignition spark is obtained after checking that wiring and stop switch are in good condition 2310RA113 TG 2 1 7 1 Ignition Timing Ignition timing is fixed and cannot be adjusted during repair work Since there is no mechanical wear in these systems ignition timing cannot get out of adjustment during operation 7 2 Preseparator Remove the fan housing b 8 2 Take out the screw 1 Chec...

Page 47: ... that the terminal butts against the stop arrow and its crimped side faces the screw head Fit the screw 2 with washer do not tighten down yet 2310RA119 TG 1 2 3 2310RA120 TG 1 2 Push the ignition module back and slide the setting gauge 1 1111 890 6400 between the arms of the ignition module and the flywheel magnet poles The setting gauge is not shown in the illustration The flywheel must turn free...

Page 48: ...h the retainer 1 into the slot arrow until it snaps into position Reassemble all other parts in the reverse sequence 7 4 Testing the Ignition Module To test the ignition module use either the ZAT 4 ignition system tester 5910 850 4503 or the ZAT 3 ignition system tester 5910 850 4520 2310RA125 TG 1 2 2310RA126 TG 1 The ignition test refers only to a spark test not to ignition timing Using ZAT 4 ig...

Page 49: ...e ignition system is in order If no spark is visible in the window 3 check the ignition system with the aid of the troubleshooting chart b 7 8 7 5 Spark Plug Boot Ignition Lead The ignition module 1 and ignition lead 2 form a unit A new ignition module must be installed if the ignition lead is damaged Remove the shroud b 6 4 Remove the spark plug boot and pull the ignition lead out of the guides b...

Page 50: ...rn Tap the puller 1 sharply to release the flywheel 2 from its tapered seat Take care not to damage the pawls on models with ErgoStart Take the puller 1 5910 893 4504 off the crankshaft and remove the flywheel The flywheel and magnet poles arrows must not be damaged or have turned blue Replace flywheel if necessary 2310RA097 TG 1 2 0001RA167 TG On models with ErgoStart check the pawls for damage a...

Page 51: ... spring and replace the wiring harness if necessary If no fault can be found check the ignition system with the aid of the troubleshooting chart b 7 8 Reassemble in the reverse sequence 7 7 2 Removing and Installing Remove the shroud b 6 4 Pull the boot off the spark plug Remove the fan housing b 8 2 Remove the choke rod b 10 3 3 Pull the retainers 1 and 2 carefully out of the slots arrows and ope...

Page 52: ...e tube 1 locates in the grommet 2 Position the wiring harness 1 so that the protective tube 2 points towards the ignition module 2310RA137 TG 1 2 2 2310RA138 TG 1 Push the grommet 1 into the recess arrow in the air guide shroud 2 until it is flush with the outside edge The ground wire 1 must be below the short circuit wire 2 Position the wiring harness 1 in the retainer 2 so that about 5 mm a of t...

Page 53: ... wire 2 make sure the terminal is pushed fully home Press the short circuit wire 2 fully into the guide arrow Check that the ignition lead 1 is properly seated in the guide Carefully push the retainers 2 and 3 into the slots arrows until they snap into place Position filter base in the carburetor box 2310RA144 TG 1 2 2310RA145 TG 1 3 2 Position the switch lever 1 in the carburetor box Position ter...

Page 54: ...re Test and install the ground wire as described for the short circuit wire Check for contact and continuity and replace the wiring harness if necessary b 7 7 7 7 4 Contact Spring The ground wire must be firmly seated in the contact spring s loop perform contact and continuity test if necessary b 7 7 1 Pull the filter base off the studs b 12 3 Swing the filter base 1 to one side 2310RA150 TG 1 Lif...

Page 55: ... pushing the contact spring 1 fully home lift it a little and ease it over the switch level no more than 2 mm 2310RA424 TG 1 2 2310RA152 TG 2 1 2310RA153 TG 1 Push the contact spring 1 into the guide arrows until it is engaged by the tab Install the filter base b 12 3 Check operation short circuit wire s terminal sleeve must touch the contact spring arrow in position 0 Reassemble all other parts i...

Page 56: ...tacts shorted Clean readjust or replace the plug b 7 4 Check the spark plug boot Firmly seated on plug leg spring Leg spring hook in center of ignition lead Boot damaged If necessary install new spark plug boot and or leg spring b 7 5 Test ignition system with ZAT 3 or ZAT 4 use ZAT 3 as main spark gap see TI 32 94 b 7 4 1 All manuals and user guides at all guides com a l l g u i d e s c o m ...

Page 57: ... plug boot Holes cracks Resistance spark plug boot to ground spec 1 5 12 kΩ Check resistance of ignition lead spark plug boot and ignition module removed Spec 10 Ω If necessary install new spark plug boot and or ignition module b 7 5 Check short circuit wire Wire damaged Connectors firmly seated Check continuity replace wiring harness if necessary b 7 7 1 1 3 yes no 2 Powerful spark All manuals an...

Page 58: ...uretor Check engine for leaks Check position of flywheel on crankshaft b 6 2 b 7 6 yes Check operation of stop switch Short circuit wire chafed Function between contact spring and switch shaft contact Position F no connection Position 0 connection replace the wiring harness if necessary b 7 7 2 2 3 Powerful spark Engine runs All manuals and user guides at all guides com ...

Page 59: ...b 14 If clogged with dirt or pitch the entire starter mechanism including the rewind spring must be removed and disassembled Take particular care when removing the rewind spring Clean all components Models with ErgoStart Relieve tension of rewind spring b 8 4 8 2 Fan housing Remove the shroud b 6 4 Take out the screw 1 with sleeve and screws arrows Lift the hand guard a little and remove the fan h...

Page 60: ...tor turns and the peg on the pawl moves in the direction of the spring loop the pawl moves outwards Reassemble all other parts in the reverse sequence 2310RA206 TG 1 2310RA207 TG Models with ErgoStart Remove the ErgoStart b 8 4 Two pawls are installed in models with ErgoStart The removal procedure is the same as for the standard version Lubricate the seats of the new pawls b 14 Fit the new pawls a...

Page 61: ... the pins 2 on the flywheel preload the torsion springs at the same time and locate them against the ribs arrow Fit the pawls 1 so that they can move towards the center of the flywheel as far as stop arrow Fit the E clips 2 533RA198 TG 1 1 5902RA581 TG 2 1 2710RA274 TG 2 1 Check operation Pawls must move freely and be held against the stop by the torsion springs Push the spring housing 1 over the ...

Page 62: ...ut and unwind Check the rope rotor and replace if necessary Coat bore in rope rotor with STIHL special lubricant b 14 Installing Fit the rope rotor on the starter post so that the inner spring loop arrow engages the recess 1 The recess in the hub of the rope rotor is the anchor point for the spring Fit the cover washer 2310RA213 TG 2 1 2310RA214 TG 1 Install the pawl s and spring clip b 8 3 Instal...

Page 63: ...e 1 through the side of the rope rotor Secure the rope 1 with a simple overhand knot 4903RA132 TG 2310RA216 TG 1 2310RA217 TG 1 Pull the rope 1 back into the rotor until the knot locates in the recess arrow Tension the rewind spring b 8 7 Reassemble all other parts in the reverse sequence 8 7 Tensioning the Rewind Spring Remove the fan housing and the segment b 8 2 Pull out a short length of start...

Page 64: ...wind Spring Troubleshooting b 3 4 The replacement spring in a spring housing comes ready for installation Wear a face shield and work gloves to protect your eyes and hands from injury Remove the fan housing and the segment b 8 2 Relieve tension of rewind spring if necessary and remove the rope rotor b 8 5 Remove any remaining pieces of the old rewind spring If the rewind spring can no longer be pr...

Page 65: ...g If the rewind spring has popped out refit it in the fan housing as follows Arrange the rewind spring 1 in its original position Fit the anchor loop in its seat arrow in the fan housing Fit the rewind spring 1 clockwise in the housing holding the windings steady in the process The procedure is otherwise the same as that for installing a new rewind spring 2310RA230 TG 1 2310RA231 TG 1 Models with ...

Page 66: ...nd spring in frame As the spring seat is deeper on models with ErgoStart the rewind spring can only fitted directly in the fan housing if it is preassembled in a frame If the rewind spring has popped out refit it in the frame as follows Fit the anchor loop in its seat arrow in the frame Fit the rewind spring 1 counterclockwise in the frame holding the windings steady in the process The procedure i...

Page 67: ... Unscrew the AV spring 1 with bearing plug 2 2310RA232 TG 1 2310RA233 TG 2 1 Check the AV spring and plug replace if necessary Installing The bearing plug 1 must be screwed into the AV spring 2 as far as stop Screw the AV spring 2 with bearing plug 1 onto the plug arrow as far as stop Install the tank housing b 12 11 5 Insert and tighten down the screw 1 firmly Reassemble all other parts in the re...

Page 68: ...ngages the peg arrow Push the tank housing 1 upwards and hold it there Position the bearing plug 2 and cover 3 so that their bores are in line with the bore in the tank housing Insert and tighten down the screws 4 and 5 firmly Reassemble all other parts in the reverse sequence 2310RA240 TG 1 2310RA241 TG 4 1 3 2 5 9 3 AV Spring on Handlebar The AV spring is located between the handle frame and cyl...

Page 69: ... are installed between the engine housing and tank housing at the ignition and clutch sides Remove the tank housing b 12 11 5 Pry out the stop buffer 1 at the ignition and clutch sides Install new stop buffers 2310RA246 TG 2 1 5902RA247 TG 1 Installing Position the stop buffers 1 at both sides the tapered ends arrow must face the engine housing Use STIHL press fluid to simplify assembly b 14 Push ...

Page 70: ...bores arrows Use STIHL press fluid to simplify assembly b 14 Push the tapered ends of the buffers 1 fully into the bores arrows turning them back and forth to simplify installation The tapered ends arrows must be properly seated on the other sides of the bores 2310RA251 TG 1 1 2310RA252 TG Push the tank housing 1 upwards and hold it there Insert and tighten down the screw 2 firmly Reassemble all o...

Page 71: ...AV spring and replace if necessary b 9 3 Installing Place the handlebar in position Lift the handlebar 1 lug 2 first into the recess arrow until it locates in the tank housing seat Insert the screws and tighten them down firmly Ease the handlebar 1 sideways and place it in the guide arrow Insert the screws and tighten them down firmly 2 2310RA158 TG 1 2310RA159 TG 1 Place plug 1 of AV spring on th...

Page 72: ...sary 2310RA160 TG 2 1 2310RA161 TG 1 Check the filter base and replace it if necessary Installing Position filter base in the carburetor box Position the switch lever 1 in the carburetor box Fit the short circuit wire on the switch lever b 7 7 2 Position the switch lever 1 so that the short circuit wire points towards the filter base and the opening arrow lines up with the web 2 2310RA162 TG 1 2 2...

Page 73: ...er 3 with torsion spring 4 Inspect the lockout lever throttle trigger and torsion spring replace as necessary Installing Attach the torsion spring 1 to the trigger 2 note the installed position arrow 2310RA167 TG 2 1 2310RA168 TG 1 2 4 3 2310RA169 TG 2 1 Place the throttle trigger 1 in the rear handle so that the tongue arrow is within the handle and the holes in the throttle trigger and handle ar...

Page 74: ...tle Trigger Lockout Lever QuickStop Super Lubricate sliding and bearing points with grease after disassembly To remove the handle molding press the tabs 1 on the underside apart and push them through the rear handle Remove the handle molding 1 5902RA307 TG 1 1 2310RA175 TG 1 Take the throttle rod 1 out of the guide arrow and disconnect it from the throttle trigger 2 Use a drift 2 to drive out the ...

Page 75: ...ch the throttle rod 1 to the throttle trigger 2 and fit it in the guide arrow Lubricate roller on throttle trigger with grease b 14 Engage lugs 2 at front end of handle molding 1 in the recesses arrow Press the lockout lever down 3 2310RA182 TG 2 1 2 2310RA183 TG 1 2310RA174 TG 1 2 Push down the handle molding 1 until it snaps into position Check operation Reassemble all other parts in the reverse...

Page 76: ...the handle molding b 10 3 Use a drift 1 to drive out the pin arrow Take out the lockout lever Push out the bushing 1 Remove the torsion spring 2 Inspect the lockout lever torsion spring and bushing replace as necessary 2310RA188 TG 1 2310RA189 TG 1 2 Installing Position the torsion spring 1 and fit it in the lockout lever Push the bushing 2 into the bore arrow the torsion spring is held in positio...

Page 77: ... rod 1 fully into its seat arrow Check operation Check that the choke rod is properly seated Reassemble all other parts in the reverse sequence 10 3 4 Throttle Rod Remove the throttle trigger b 10 2 QuickStop Super b 10 3 Remove the choke rod b 10 3 3 Remove the baffle b 12 2 Pry the filter base 1 out of the buffer 2 2310RA194 TG 2 1 2 2310RA195 TG 1 Pull the filter base 1 off the studs arrows Pul...

Page 78: ...le cable 1 between tank and engine housings and through the opening arrow in the direction of the rear handle Push the throttle rod 1 into the guide 2 in the carburetor carrier until it snaps into position 1 2310RA294 TG 12310RA295 TG 2 1 2310RA296 TG Install the throttle trigger b 10 2 Push the carburetor 1 with fuel hose 2 over the studs take care not to overstretch the fuel hose 2 Models with m...

Page 79: ...k cap and drain the oil tank b 1 Remove the clutch b 4 Remove the brake band b 5 2 Remove the oil pump b 11 3 Remove the oil suction hose 1 together with the pickup body Check the oil suction hose and pickup body and replace if necessary Fit the pickup body b 11 1 Installing Push the oil suction hose 1 pickup body first through the housing bore arrow 2310RA299 TG 1 2310RA300 TG 1 Line up the oil s...

Page 80: ...ws are in alignment Position the oil suction hose 1 so that the straight sides of the lugs arrows locate against the engine housing Push the oil suction hose 1 onto the nipple 2310RA305 TG 1 2310RA306 TG 1 2310RA307 TG 1 Place oil pump 1 in position and push the tube 2 into its seat arrow until it is flush with the engine housing Fit the screw 3 and tighten it down firmly Push the worm home as far...

Page 81: ... carefully drive the valve out of the housing from inside the tank Installing Check correct installed position Insert the valve in the housing bore arrow Use a 6 mm drift to carefully drive in the new valve from outside note installed depth 2310RA310 TG 2310RA311 TG Drive the new valve into the bore to a depth of 1 0 1 mm a Reassemble all other parts in the reverse sequence 219RA479 TG All manuals...

Page 82: ...TG 1 12 2 Baffle Remove the air filter b 12 1 Unscrew the nuts arrows Remove the baffle 1 Check the baffle and replace it if necessary Reassemble in the reverse sequence 12 3 Filter Base Remove the air filter b 12 1 Remove the choke rod b 10 3 3 Remove the baffle b 12 2 Pry the filter base 1 out of the buffer 2 2310RA313 TG 1 2 2310RA195 TG 1 Pull the filter base 1 off the studs arrows Pull the fi...

Page 83: ...id to simplify assembly b 14 Push the filter base 1 into the buffer 2 collar of peg must project fully on the other side of the buffer 2 2310RA316 TG 1 3 2310RA317 TG 1 2 2310RA318 TG 1 Install the choke rod b 10 3 3 Use punch down tool 5910 890 4000 to press the short circuit wire 1 into the guides arrows so that the marking 2 is at the edge of the guide and the protective tube 3 locates below th...

Page 84: ...d out Ease the air guide shroud 1 over the stop arrow and lift it a little Push the manifold flange 1 out of the air guide shroud 2 in the direction of the cylinder and pull the air guide shroud away at the same time Pull the fuel hose out of the air guide shroud Remove the air guide shroud 2310RA321 TG 1 2310RA322 TG 1 2310RA323 TG 2 1 Pull out the shutter check it and replace if necessary Instal...

Page 85: ... Line up grommet 1 of fuel hose 2 so that its straight side arrow butts against the edge of the air guide shroud Ease the air guide shroud 1 over the stop arrow and push it into its seat Insert and tighten down the screws 2 firmly Install the carburetor carrier b 12 8 Install the throttle rod b 10 3 4 Install the carburetor b 12 5 2310RA329 TG 2 1 2310RA330 TG 1 2 2 Push the rubber grommet 1 into ...

Page 86: ...he carburetor carrier b 12 8 2310RA332 TG 1 Take out the screw 1 Remove the connector 2 and disconnect it from the fuel return hose 3 Pull the fuel return hose 1 out of the guides arrows Take out the screws 1 2310RA333 TG 1 2 3 2310RA334 TG 1 2310RA335 TG 1 1 Push the grommet arrow of the fuel hose 1 downwards and out Ease the air guide shroud 1 over the stop arrow and lift it a little Push the ma...

Page 87: ... simplify installation b 14 Fit the grommet 1 in the hole arrow and make sure it is properly seated Install fuel pump with fuel hoses and elbow connector b 12 11 4 To fit the manifold 2 through the air guide shroud s opening wind a piece of string 1 about 15 cm long around the back of manifold flange 2310RA324 TG 1 2310RA325 TG 2 1 Coat manifold flange with STIHL press fluid to simplify installati...

Page 88: ...tring Ease the air guide shroud 1 over the stop arrow and push it into its seat Insert and tighten down the screws 2 firmly Push the fuel return hose 1 onto the connector 2 as far as stop 2310RA345 TG 1 3 2 2310RA346 TG 2 1 2 2310RA347 TG 2 1 Position the elbow connector 1 against the stop arrow Insert and tighten down the screw 2 firmly Starting at the elbow connector 2 push the fuel return hose ...

Page 89: ...the fuel in a clean container b 1 Disconnect the fuel hose only when the tank cap is open 2310RA350 TG 1 2 3 Pull the fuel hose 1 off the nipple arrow Models with manual fuel pump Remove the fuel hose 1 All models Remove the carburetor 1 Check the carburetor and service or replace if necessary Install a new fuel hose b 12 11 2 2310RA351 TG 1 2310RA199 TG 1 2310RA352 TG 1 Models with manual fuel pu...

Page 90: ...b 12 5 Push the fuel hose 1 1110 141 8600 on to the nipple 2 0000 855 9200 Push the fuel hose with nipple onto the carburetor s fuel stub arrow 2310RA254 TG 1 2 Push the pressure hose of pump 0000 850 1300 onto the nipple Push the ring 1 to the right and pump air into the carburetor until the pressure gauge 2 indicates a pressure of about 0 8 bar 80 kPa If this pressure remains constant the carbur...

Page 91: ...rts and swells and has to be replaced Check the metering diaphragm for signs of damage and wear Install a new gasket Installing Note installed positions of metering diaphragm 2 and gasket 1 Position the gasket 1 and metering diaphragm 2 so that pegs arrows engage the small holes in the tabs 2310RA256 TG 1 2 2310RA259 TG 1 2 Position the end cover 1 so that the stub 3 points in the direction of the...

Page 92: ... the bore Position the inlet control lever 3 with spindle 2 on the spring arrow first then slide the inlet control lever s clevis into the groove in the inlet needle 1 Make sure the spring locates on the control lever s nipple Press the inlet control lever down and secure it with the screw Check that the inlet control lever moves freely Install the metering diaphragm b 12 6 1 2310RA263 TG 1 2 2310...

Page 93: ... Installing Place the gasket 1 and pump diaphragm 2 on the end cover 3 so that the contours arrows are in alignment and make sure they are held in position by the pegs 4 Fit the end cover 1 from below so that the pump diaphragm and gasket are still held in position Aligntheendcover 1 sothatthe contour arrow points in the direction of the throttle and choke shaft levers 2310RA268 TG 4 2 4 1 3 2310R...

Page 94: ... LA idle speed screw 3 If the carburetor cannot be adjusted properly the problem may be the adjusting screws The high speed screw H has a limiter cap which has to be removed before the screw is removed Always install a new limiter cap Low speed screw Take out the low speed screw L 1 2310RA273 TG 1 3 2 2310RA274 TG 1 Inspect the tip arrow and O ring 1 for damage or wear and replace the low speed sc...

Page 95: ...ow and O ring 1 for damage or wear and replace the high speed screw H if necessary Screw down the high speed screw H 1 as far as stop 2310RA279 TG 1 2310RA280 TG 1 Pre installing limiter cap Always install a new limiter cap Push the new limiter cap 1 on to the high speed screw H as far as the detent arrow do not push fully home The basic setting is performed through the pre installed limiter cap w...

Page 96: ...rt the screwdriver 1 5910 890 2306 through the opening arrow and into the low speed screw L and high speed screw H push the screwdriver through the pre installed limiter cap on the high speed screw H Adjust idle speed with a tachometer Adjust specified engine speeds within a tolerance of 200 rpm 1 Adjust engine speed with idle speed screw LA to 3 300 rpm 2 Turn the low speed screw L counterclockwi...

Page 97: ... setting Warm up the engine Engine stops while idling Turn the idle speed screw LA clockwise until the chain starts running then turn it back 1 full turn Saw chain runs while engine is idling Turn the idle speed screw LA counterclockwise until the chain stops running then turn it back 1 full turn Erratic idling behavior poor acceleration although standard setting is correct Idle setting too lean W...

Page 98: ...ier check it and replace if necessary Check the intake manifold and replace if necessary b 12 9 Installing To fit the manifold 2 through the carburetor carrier sopening wind a piece of string 1 about 15 cm long around the back of manifold flange 2310RA288 TG 1 2 2310RA289 TG 1 2 Coat manifold flange with STIHL press fluid b 14 Use the ends of the string 2 to pull the manifold flange 1 through the ...

Page 99: ...e shroud b 6 4 Remove the carburetor b 12 5 Remove the carburetor carrier b 12 8 Remove the air guide shroud b 12 4 Models with manual fuel pump b 12 4 1 Take out the screws arrows Remove the intake manifold 1 Inspect the intake manifold and replace it if necessary even very minor damage can cause engine running problems b 3 7 2310RA357 TG 1 Inspect and clean the sealing faces arrows b 14 The seal...

Page 100: ... on the tank via the fuel hose Open the fuel tank cap and drain the fuel tank b 1 Close the tank cap Remove the carburetor b 12 5 2310RA360 TG 1 Push the nipple 1 0000 855 9200 into the fuel hose arrow Models with manual fuel pump Use a suitable plug 2 to seal the fuel suction hose 1 2310RA361 TG 1 2 2310RA362 TG 1 Vacuum test Push the ring 1 to the left and connect the pump 2 0000 850 1300 to the...

Page 101: ...out the screw 1 2310RA364 TG 1 2 2310RA365 TG 1 Press the tank housing 1 downwards and use wooden block 2 1108 893 4800 to maintain the gap Remove the cover 1 Pry the tank vent 1 out of its seat using the rib arrow for leverage Always install a new tank vent 2310RA366 TG 1 2 2310RA367 TG 1 2310RA368 TG 1 Coat sealing ring of new tank vent with STIHL press fluid b 14 Push home the tank vent by hand...

Page 102: ...the tank Pour a small amount of clean gasoline into the tank Close the tank and shake the saw vigorously 2310RA365 TG 1 Open the tank again and drain it Dispose of fuel properly in accordance with environmental requirements b 1 Open the tank cap Use hook 5910 893 8800 to remove the pickup body 1 from the fuel tank Do not overstretch the fuel hose Pull off the pickup body 1 check it and replace if ...

Page 103: ...310RA057 TG All models Lower the tank housing Pull the fuel hose 1 downwards and out through the opening arrow Pull out the fuel hose 1 with connector Pull the connector 1 off the fuel hose 2 Remove the pickup body b 12 11 1 2310RA376 TG 1 2310RA377 TG 1 2 2310RA378 TG 1 Pull the fuel suction hose 1 out of the fuel tank Replace the fuel hose and fuel return hose Check the connector and replace if ...

Page 104: ... 1 Push the fuel hose 1 connector 2 first into the fuel suction hose so that it locates between the ribs arrows Machines with QuickStop Super Pass the fuel hose 1 connector 2 first under the brake cable and push it into the fuel suction hose so that it locates between the ribs arrows 2310RA383 TG 1 2 2310RA384 TG 1 2 Position the fuel hose 1 so that it is below the brake cable 2 as shown in the il...

Page 105: ...crews and tighten them down firmly Fit the AV spring 1 in position Insert and tighten down the screw 2 firmly Check position of fuel hose and correct if necessary b 12 11 2 2310RA159 TG 1 2310RA388 TG 2 1 Use hook 5910 893 8800 to remove the fuel suction hose 1 from the fuel tank Do not overstretch the fuel suction hose Fit the pickup body b 12 11 1 Install the air guide shroud b 12 4 Models with ...

Page 106: ...e grommet is pulled out of the adjusting screw this may change the adjustment of the brake cable Take out the screw 1 and pull the retainer 2 out of its seat Remove the fuel hose 1 b 12 11 2 Pull the fuel return hose 1 downwards and out through the opening arrow 1 2 2310RA057 TG 2310RA390 TG 12310RA391 TG 1 Pull out the connector 1 with fuel return hose 2 Pull the connector 1 off the fuel return h...

Page 107: ...tor 1 into the fuel return hose 2 as far as stop Machines with QuickStop Super Pass the fuel return hose 1 connector first under the brake cable 2 2310RA398 TG 1 2310RA399 TG 1 2 2310RA400 TG 1 2 3 4 Fit the connector 3 with fuel return hose 1 between the ribs arrows and push it into the grommet 4 The fuel return hose 1 must be under the brake cable 2 and run to the left as shown in the illustrati...

Page 108: ...s Squeeze the tabs arrows together and pull out the manual fuel pump 1 Check the oil fuel pump and replace if necessary 2310RA404 TG 2 1 2310RA406 TG 1 Installing Position the fuel pump 1 so that the lug 3 points towards the recess arrow Push the fuel pump 1 into the air guide shroud 2 until the tabs engage Push the fuel return hose 1 onto the long nipple 2 and elbow connector 3 Push the fuel suct...

Page 109: ... hoses out of the engine housing 2 at the same time Machines with QuickStop Super Pull out the tank housing and pull the brake cable out of the engine housing at the same time All models Inspect the tank housing and replace if necessary Only transfer those parts from the old tank housing that are not included with the replacement see parts list 2 2310RA410 TG 1 2 2310RA411 TG 1 Inspect stop buffer...

Page 110: ...hook 4 first passed the right hand side of the fuel hose 3 and the fuel return hose 2 and through the opening arrow Machines with QuickStop Super Push the brake cable 1 short hook 2 first through the bore arrow in the engine housing 3 1 4 2310RA058 TG 2 1 2310RA415 TG 2 All models Fit the antivibration spring 1 in the recess arrow in the engine housing Install the handlebar b 9 4 Lift the tank hou...

Page 111: ...s with torque wrench 6 Wooden assembly block 1108 893 4800 Lowering tank housing maintaining clearance 7 Assembly drift 1110 893 4700 Removing and installing piston pin 8 Setting gauge 1111 890 6400 Adjusting air gap between the ignition module and flywheel 9 Installing tool 1116 893 4800 Installing rewind spring 10 Assembly tube 1117 890 0900 Attaching springs 11 Test flange 1118 850 4200 Leakage...

Page 112: ...T 27 x 150 5910 890 2400 IS P screws 25 Hook 5910 890 2800 Detaching springs on clutch shoes 26 Assembly stand 5910 890 3101 Holding saw for repairs 27 Puller 5910 890 4400 Removing oil seals Jaws No 3 1 0000 893 3706 Removing oil seals Jaws No 6 0000 893 3711 Removing oil seals 28 Puller 5910 890 4502 Pull off the limiter cap 29 Stud puller M8 5910 893 0501 Removing bar mounting studs 30 Puller 5...

Page 113: ...bricant 0781 417 1315 Bearing bore in rope rotor rewind spring in fan housing 4 STIHL press fluid OH 723 0781 957 9000 Rubber components AV buffers 5 Dirko HT red sealant 0783 830 2000 Sealing engine pan cylinder 6 Standard commercial solvent based degreasant containing no chlorinated or halogenated hydrocarbons Cleaning sealing faces and carburetor crankshaft stubs and flywheel taper All manuals ...

Page 114: ...englisch english 0455 737 0123 M0 M10 xxx All manuals and user guides at all guides com ...

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Stihl MS 231, Manual

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