Product Instruction Manual
Page 3
... Spark Plug 39 Replacing the Starter Rope and Rewind Spring 40 Storing the Machine 42 Checking and Replacing the Chain Sprocket 43 Maintaining and Sharpening the Saw Chain 44 Maintenance and Care 47 { Main Parts Specifications Special Accessories Ordering Spare Parts Maintenance and Repairs STIHL Incorporated Federal Emission Control Warranty Statement Trademarks MS 311, MS...
... Spark Plug 39 Replacing the Starter Rope and Rewind Spring 40 Storing the Machine 42 Checking and Replacing the Chain Sprocket 43 Maintaining and Sharpening the Saw Chain 44 Maintenance and Care 47 { Main Parts Specifications Special Accessories Ordering Spare Parts Maintenance and Repairs STIHL Incorporated Federal Emission Control Warranty Statement Trademarks MS 311, MS...
Product Instruction Manual
Page 7
...tool carefully so as it checked by a spark or other personal injury from the fuel system. Fueling Instructions Warning! Warning! Take care not to get fuel on your STIHL servicing dealer. Cap with different fuel caps. In order to release slowly. MS 311, MS 391 5 In case of your clothing immediately...ignited by your clothing. In order to cool before transporting the power tool over the chain and guide bar before refueling. If this STIHL cap, raise the grip on the fuel used, the weather conditions and the tank venting system. Grip the front handle in well-...
...tool carefully so as it checked by a spark or other personal injury from the fuel system. Fueling Instructions Warning! Warning! Take care not to get fuel on your STIHL servicing dealer. Cap with different fuel caps. In order to release slowly. MS 311, MS 391 5 In case of your clothing immediately...ignited by your clothing. In order to cool before transporting the power tool over the chain and guide bar before refueling. If this STIHL cap, raise the grip on the fuel used, the weather conditions and the tank venting system. Grip the front handle in well-...
Product Instruction Manual
Page 8
...tightened the nut(s) and thereafter at regular intervals (whenever the saw with the sprocket cover loose. STIHL Oilomatic chain, guide bar and sprocket must move freely and always spring back to loosen or ... end of fuel. Always check your power tool. a loose boot may cause arcing that the spark plug boot is damaged, improperly adjusted or maintained, or not completely or securely assembled. it is... you must be used as an aid in gauge and pitch. Proper tension of injury. 6 MS 311, MS 391 Warning! Proper starting methods reduce the risk of the chain is shut off the engine and...
...tightened the nut(s) and thereafter at regular intervals (whenever the saw with the sprocket cover loose. STIHL Oilomatic chain, guide bar and sprocket must move freely and always spring back to loosen or ... end of fuel. Always check your power tool. a loose boot may cause arcing that the spark plug boot is damaged, improperly adjusted or maintained, or not completely or securely assembled. it is... you must be used as an aid in gauge and pitch. Proper tension of injury. 6 MS 311, MS 391 Warning! Proper starting methods reduce the risk of the chain is shut off the engine and...
Product Instruction Manual
Page 12
... or cancer. If you do not have any questions as rocks, fences, nails and the like. Do not operate your STIHL servicing dealer only. 10 MS 311, MS 391 This may indicate damage, breakage or excessive wear. Replace damaged, broken or excessively worn antivibration elements immediately, since they...elements should be replaced in overheating and damage to reduce the risk of personal injury in heat radiation or sparks, thereby increasing the risk of the cylinder, spark plug) become hot during normal operation may occur if the throttle is depressed for a while after the ...
... or cancer. If you do not have any questions as rocks, fences, nails and the like. Do not operate your STIHL servicing dealer only. 10 MS 311, MS 391 This may indicate damage, breakage or excessive wear. Replace damaged, broken or excessively worn antivibration elements immediately, since they...elements should be replaced in overheating and damage to reduce the risk of personal injury in heat radiation or sparks, thereby increasing the risk of the cylinder, spark plug) become hot during normal operation may occur if the throttle is depressed for a while after the ...
Product Instruction Manual
Page 24
...for periodic inspection and servicing of fire and hearing loss. Warning! If your saw if the screen is a change in the instruction manual). 22 MS 311, MS 391 replace worn sprockets or chains. every three months, Moderate usage - For any maintenance of the emission control system please refer to the maintenance chart... in a dry place and away from the spark plug or with a spark-arresting screen to reduce the risk of the chain brake and can spot a dull chain when easy-to-cut wood becomes hard to cut and burn marks appear on your STIHL chain saw to trained personnel such as your...
...for periodic inspection and servicing of fire and hearing loss. Warning! If your saw if the screen is a change in the instruction manual). 22 MS 311, MS 391 replace worn sprockets or chains. every three months, Moderate usage - For any maintenance of the emission control system please refer to the maintenance chart... in a dry place and away from the spark plug or with a spark-arresting screen to reduce the risk of the chain brake and can spot a dull chain when easy-to-cut wood becomes hard to cut and burn marks appear on your STIHL chain saw to trained personnel such as your...
Product Instruction Manual
Page 35
...n - the chain saw chain is running STOP 1 0 2 N Press the throttle trigger interlock and blip the throttle trigger (2); see "Spark plug" N Dry spark plug N Crank the engine several times with the chain brake on the decompression valve N Restart the engine English N Move the Master Control ... stop position 0 N Remove the spark plug - see "Winter Operation" Switch off . to the stop position 0 - even if the engine is off engine N Press the button on (saw is released - Open the throttle only when the chain brake is cold MS 311, MS 391 33 the Master Control lever ...
...n - the chain saw chain is running STOP 1 0 2 N Press the throttle trigger interlock and blip the throttle trigger (2); see "Spark plug" N Dry spark plug N Crank the engine several times with the chain brake on the decompression valve N Restart the engine English N Move the Master Control ... stop position 0 N Remove the spark plug - see "Winter Operation" Switch off . to the stop position 0 - even if the engine is off engine N Press the button on (saw is released - Open the throttle only when the chain brake is cold MS 311, MS 391 33 the Master Control lever ...
Product Instruction Manual
Page 39
Standard setting MS 311, MS 391 LA N Shut off the engine N Check the air filter and clean or replace if necessary. With this carburetor it is a risk of engine damage due to correct the adjusting screws within fine limits. N Check the spark arresting screen (country-specific) in the muffler and clean or replace if necessary...
Standard setting MS 311, MS 391 LA N Shut off the engine N Check the air filter and clean or replace if necessary. With this carburetor it is a risk of engine damage due to correct the adjusting screws within fine limits. N Check the spark arresting screen (country-specific) in the muffler and clean or replace if necessary...
Product Instruction Manual
Page 40
Chain runs when engine is damaged or heavily carbonized, fit a new one full turn. then turn it down. 0001BA009 KN 38 MS 311, MS 391 Fine tuning for the muffler to the low speed screw (L). It is usually necessary to change the setting of the idle speed ... engine is too lean: Turn the low speed screw (L) counterclockwise until the chain begins to insufficient lubrication and overheating. N If the engine is equipped with a spark arresting screen. N Turn the low speed screw (L) carefully clockwise as far as stop (no further than 3/4 turn). A slight correction of a turn (45...
Chain runs when engine is damaged or heavily carbonized, fit a new one full turn. then turn it down. 0001BA009 KN 38 MS 311, MS 391 Fine tuning for the muffler to the low speed screw (L). It is usually necessary to change the setting of the idle speed ... engine is too lean: Turn the low speed screw (L) counterclockwise until the chain begins to insufficient lubrication and overheating. N If the engine is equipped with a spark arresting screen. N Turn the low speed screw (L) carefully clockwise as far as stop (no further than 3/4 turn). A slight correction of a turn (45...
Product Instruction Manual
Page 41
... form on the insulator nose which may result in trouble in operation. N Clean dirty spark plug. N Check electrode gap (A) and readjust if necessary - MS 311, MS 391 39 Spark Plug If engine is blocked 1 4903BA007 KN English N Remove spark plug - N Use only resistor type spark plugs of spark plug: N Too much oil in operation. see "Specifications". Fit a new...
... form on the insulator nose which may result in trouble in operation. N Clean dirty spark plug. N Check electrode gap (A) and readjust if necessary - MS 311, MS 391 39 Spark Plug If engine is blocked 1 4903BA007 KN English N Remove spark plug - N Use only resistor type spark plugs of spark plug: N Too much oil in operation. see "Specifications". Fit a new...
Product Instruction Manual
Page 42
... upward N Pull the bottom of fire and burn injury, use only spark plugs authorized by STIHL. To reduce the risk of the fan housing away from the crankcase and remove downwards 4903BA005 KN 40 MS 311, MS 391 Always press spark plug boot (2) snugly onto spark plug terminal (1) of the proper size. (Note: If terminal has detachable...
... upward N Pull the bottom of fire and burn injury, use only spark plugs authorized by STIHL. To reduce the risk of the fan housing away from the crankcase and remove downwards 4903BA005 KN 40 MS 311, MS 391 Always press spark plug boot (2) snugly onto spark plug terminal (1) of the proper size. (Note: If terminal has detachable...
Product Instruction Manual
Page 50
... (very dusty work or daily after 10 to normal operating conditions only. chain must not rotate X X Readjust idle Spark Plug Readjust electrode gap Replace after every 100 operating hours All accessible screws and nuts (not adjusting screws) 3) Retighten Sparl... X Chain catcher Replace Safety labels Replace 1) STIHL recommends a STIHL servicing dealer. 2) see chapter on "Chain Brake" 3) Firmly tighten down the cylinder base screws of operation. 4) not in all versions, market-specific X X X X X X X X X X 48 MS 311, MS 391 English The following intervals apply to 20 hours...
... (very dusty work or daily after 10 to normal operating conditions only. chain must not rotate X X Readjust idle Spark Plug Readjust electrode gap Replace after every 100 operating hours All accessible screws and nuts (not adjusting screws) 3) Retighten Sparl... X Chain catcher Replace Safety labels Replace 1) STIHL recommends a STIHL servicing dealer. 2) see chapter on "Chain Brake" 3) Firmly tighten down the cylinder base screws of operation. 4) not in all versions, market-specific X X X X X X X X X X 48 MS 311, MS 391 English The following intervals apply to 20 hours...
Product Instruction Manual
Page 51
... 2 4 # 1 6 11 7 12 8 10 9 13 16 17 15 18 20 22 19 23 21 14 24 English 1 Shroud Lock 2 Carburetor Adjusting Screws 3 Spark Plug Boot 4 Shutter (Summer and Winter Operation) 5 Decompression Valve (Automatically Resetting) 6 Chain Brake 7 Chain Sprocket 8 Chain Sprocket Cover 9 Chain Catcher 10 Side Chain Tensioner ...11 Bumper Spike 12 Guide Bar 13 Oilomatic Saw Chain 14 Oil Filler Cap 15 Muffler (with Spark Arresting Screen, not Fitted on all Markets) 16 Front Hand Guard 17 Front Handle (Handlebar) 18 Starter Grip 19 Fuel Filler Cap 20...
... 2 4 # 1 6 11 7 12 8 10 9 13 16 17 15 18 20 22 19 23 21 14 24 English 1 Shroud Lock 2 Carburetor Adjusting Screws 3 Spark Plug Boot 4 Shutter (Summer and Winter Operation) 5 Decompression Valve (Automatically Resetting) 6 Chain Brake 7 Chain Sprocket 8 Chain Sprocket Cover 9 Chain Catcher 10 Side Chain Tensioner ...11 Bumper Spike 12 Guide Bar 13 Oilomatic Saw Chain 14 Oil Filler Cap 15 Muffler (with Spark Arresting Screen, not Fitted on all Markets) 16 Front Hand Guard 17 Front Handle (Handlebar) 18 Starter Grip 19 Fuel Filler Cap 20...
Product Instruction Manual
Page 52
... Helps to reduce the risk of operator contact by the engine and cutting attachment to the operator's hands. (not illustrated) 50 MS 311, MS 391 Is activated in winter position. 5 Decompression Valve (Automatically Resetting) Releases compression pressure to make engine starting throttle, run and stop... 23 Rear Handle The support handle for the shroud. 2 Carburetor Adjusting Screws For tuning the carburetor. 3 Spark Plug Boot Connects the spark plug with Spark Arresting Screen, not Fitted on all Markets) Muffler reduces engine exhaust noise and diverts exhaust gases away from touching...
... Helps to reduce the risk of operator contact by the engine and cutting attachment to the operator's hands. (not illustrated) 50 MS 311, MS 391 Is activated in winter position. 5 Decompression Valve (Automatically Resetting) Releases compression pressure to make engine starting throttle, run and stop... 23 Rear Handle The support handle for the shroud. 2 Carburetor Adjusting Screws For tuning the carburetor. 3 Spark Plug Boot Connects the spark plug with Spark Arresting Screen, not Fitted on all Markets) Muffler reduces engine exhaust noise and diverts exhaust gases away from touching...
Product Instruction Manual
Page 53
... and chain MS 311: 14.1 lbs. (6.4 kg) MS 391: 14.1 lbs. (6.4 kg) Cutting attachment Recommended cutting attachments in compliance with bar and chain: 13000 rpm Ignition system Electronic magneto ignition Spark plug (suppressed): Electrode gap: NGK BPMR 7 A, Bosch WSR 6 F 0.02 in . (1.6 mm) MS 311, MS 391 51 Category A = 300 hours B = 125 hours C = 50 hours Engine STIHL single cylinder...
... and chain MS 311: 14.1 lbs. (6.4 kg) MS 391: 14.1 lbs. (6.4 kg) Cutting attachment Recommended cutting attachments in compliance with bar and chain: 13000 rpm Ignition system Electronic magneto ignition Spark plug (suppressed): Electrode gap: NGK BPMR 7 A, Bosch WSR 6 F 0.02 in . (1.6 mm) MS 311, MS 391 51 Category A = 300 hours B = 125 hours C = 50 hours Engine STIHL single cylinder...
Product Instruction Manual
Page 57
... (see also instruction "Fuel"). Trademarks English STIHL Registered Trademarks STIHL® { K The color combination orange-... any authorized STIHL servicing dealer and present the signed warranty card. Spark Plug - Catalytic... Converter (if applicable) - and #3,400,476) 4-MIX® AUTOCUT® EASYSTART® FARM BOSS® OILOMATIC® STIHL Cutquik® STIHL DUROMATIC® STIHL Quickstop® STIHL ROLLOMATIC® STIHL WOOD BOSS® TIMBERSPORTS® YARD BOSS® Some of STIHL... Fasteners Where to STIHL Incorporated specifications that ...
... (see also instruction "Fuel"). Trademarks English STIHL Registered Trademarks STIHL® { K The color combination orange-... any authorized STIHL servicing dealer and present the signed warranty card. Spark Plug - Catalytic... Converter (if applicable) - and #3,400,476) 4-MIX® AUTOCUT® EASYSTART® FARM BOSS® OILOMATIC® STIHL Cutquik® STIHL DUROMATIC® STIHL Quickstop® STIHL ROLLOMATIC® STIHL WOOD BOSS® TIMBERSPORTS® YARD BOSS® Some of STIHL... Fasteners Where to STIHL Incorporated specifications that ...
Parts Diagram
Page 4
... 15x25x5 2 Oil seal 15x25x5 (B) (24.96),(39.90) 1 Circlip 15x1 1 Muffler gasket 1 Muffler (1,3) ☐ 20 1 Muffler (2,4) USDA Cert. I.D. 1140/01 USA ☐ 20 - 22 2 Plug 1 spark arresting screen (2,4) 1 Self-tapping screw M4x9.6 (2,4) 2 Spline screw IS-M5x16 1 Tube of sealant Dirko HT red (B) (1) MS 311, (2) MS 311-Z, (3) MS 391, (4) MS 391-Z MS 311, MS 391 4 SCS 01-2010 3.29
... 15x25x5 2 Oil seal 15x25x5 (B) (24.96),(39.90) 1 Circlip 15x1 1 Muffler gasket 1 Muffler (1,3) ☐ 20 1 Muffler (2,4) USDA Cert. I.D. 1140/01 USA ☐ 20 - 22 2 Plug 1 spark arresting screen (2,4) 1 Self-tapping screw M4x9.6 (2,4) 2 Spline screw IS-M5x16 1 Tube of sealant Dirko HT red (B) (1) MS 311, (2) MS 311-Z, (3) MS 391, (4) MS 391-Z MS 311, MS 391 4 SCS 01-2010 3.29
Parts Diagram
Page 10
... 1 Torsion spring 5 1106 405 1000 1 Spark plug boot 6 0000 435 8400 1 Sleeve 7 0000 400 7000 1 Spark plug NGK BPMR7A 7 1110 400 7005 1 Spark plug Bosch WSR 6 F 8 9075 478 3018 2 Pan head self-tapping screw IS-D4x18 9 9291 021 0100 2 Washer 4.3 10 1140 440 3003 1 Wiring harness (1) MS 311, (2) MS 311-Z, (3) MS 391, (4) MS 391-Z MS 311, MS 391 10 SCS 01-2010...
... 1 Torsion spring 5 1106 405 1000 1 Spark plug boot 6 0000 435 8400 1 Sleeve 7 0000 400 7000 1 Spark plug NGK BPMR7A 7 1110 400 7005 1 Spark plug Bosch WSR 6 F 8 9075 478 3018 2 Pan head self-tapping screw IS-D4x18 9 9291 021 0100 2 Washer 4.3 10 1140 440 3003 1 Wiring harness (1) MS 311, (2) MS 311-Z, (3) MS 391, (4) MS 391-Z MS 311, MS 391 10 SCS 01-2010...
User Manual
Page 2
... 8.5 Starter Rope / Grip 53 8.6 Tensioning the Rewind Spring 54 8.7 Replacing the Rewind Spring 55 RA_542_00_01_01 MS 311, MS 391 q © ANDREAS STIHL AG & Co. KG, 2009 1 Contents 1. Chain Brake 8 7.1 Ignition Timing 7.2 Preseparator 7.3 Ignition Module 9 7.4 Testing the 10 Ignition Module 11 7.5 Spark Plug Boot / 12 Ignition Lead 13 7.6 Flywheel 16 7.7 Short Circuit Wire 7.7.1 Testing 7.7.2 Removing and...
... 8.5 Starter Rope / Grip 53 8.6 Tensioning the Rewind Spring 54 8.7 Replacing the Rewind Spring 55 RA_542_00_01_01 MS 311, MS 391 q © ANDREAS STIHL AG & Co. KG, 2009 1 Contents 1. Chain Brake 8 7.1 Ignition Timing 7.2 Preseparator 7.3 Ignition Module 9 7.4 Testing the 10 Ignition Module 11 7.5 Spark Plug Boot / 12 Ignition Lead 13 7.6 Flywheel 16 7.7 Short Circuit Wire 7.7.1 Testing 7.7.2 Removing and...
User Manual
Page 6
...: Idle speed: Clutch: Clutch engages at: Engine housing leakage test at gauge pressure: under vacuum: 2.2 Fuel System 2.3 Ignition System 2.4 Chain Lubrication MS 311, MS 391 MS 311 59 cm3 47 mm 34 mm 3 kW (4 bhp) at 9,500 rpm 13,000 rpm 2,800 rpm Centrifugal clutch without linings 3,500 rpm 0.5 ...: Operation of tank vent at gauge pressure: Fuel: 0.8 bar 0.5 bar as specified in instruction manual Air gap between ignition module and fanwheel: Spark plug (resistor type): Electrode gap: 0.20...0.30 mm NGK BPMR 7 A BOSCH WSR6F 0.5 mm Speed-controlled oil pump with reciprocating piston and ...
...: Idle speed: Clutch: Clutch engages at: Engine housing leakage test at gauge pressure: under vacuum: 2.2 Fuel System 2.3 Ignition System 2.4 Chain Lubrication MS 311, MS 391 MS 311 59 cm3 47 mm 34 mm 3 kW (4 bhp) at 9,500 rpm 13,000 rpm 2,800 rpm Centrifugal clutch without linings 3,500 rpm 0.5 ...: Operation of tank vent at gauge pressure: Fuel: 0.8 bar 0.5 bar as specified in instruction manual Air gap between ignition module and fanwheel: Spark plug (resistor type): Electrode gap: 0.20...0.30 mm NGK BPMR 7 A BOSCH WSR6F 0.5 mm Speed-controlled oil pump with reciprocating piston and ...
User Manual
Page 7
... screw Collar screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Carrier Screw Screw Screw Screw Screw Nut Screw Screw Spark plug Screw P 4x14 Chain tensioner cover/engine housing 1.5 P 4x12 Brake band/engine housing 2.0 M 10 Collar stud for bar / engine pan ...Muffler / cylinder 10.0 M 8x1 Flywheel/crankshaft 33.0 M 5 Carburetor/collar stud 3.5 P 4x14 Pre-separator / engine housing 2.0 P 4x12 Cover plate/fan housing 2.0 M 14x1.25 Spark plug 25.0 D 4x18 Ignition module / engine pan 4.0 1) 3) 4) 3) 3) 3) 1) 3) 5) 3) 6 MS 311, MS 391
... screw Collar screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Screw Carrier Screw Screw Screw Screw Screw Nut Screw Screw Spark plug Screw P 4x14 Chain tensioner cover/engine housing 1.5 P 4x12 Brake band/engine housing 2.0 M 10 Collar stud for bar / engine pan ...Muffler / cylinder 10.0 M 8x1 Flywheel/crankshaft 33.0 M 5 Carburetor/collar stud 3.5 P 4x14 Pre-separator / engine housing 2.0 P 4x12 Cover plate/fan housing 2.0 M 14x1.25 Spark plug 25.0 D 4x18 Ignition module / engine pan 4.0 1) 3) 4) 3) 3) 3) 1) 3) 5) 3) 6 MS 311, MS 391