Instruction Manual
Page 2
... ErgoStart 60 8.5 Rope Rotor 61 8.6 Starter Rope / Grip 61 8.7 Tensioning the Rewind Spring 62 8.8 Replacing the Rewind Spring 63 9. QuickStop Super 73 10.3.1 Switch Lever QuickStop Super 74 10.3.2 Lockout Lever - ... Leakage Test 89 RA_737_00_01_01 MS 231, MS 231 C, MS 251, MS 251 C q © ANDREAS STIHL AG & Co. Specifications 5 2.1 Engine 5 2.2 Fuel System 5 2.3 Ignition System 5 2.4 Chain Lubrication 5 2.5 Tightening Torques 6 3. Troubleshooting 8 3.1 Clutch 8 3.2 Chain Drive, Chain Brake, Chain Tensioner 9 3.3 Chain Lubrication 11 3.4 Rewind Starter...
... ErgoStart 60 8.5 Rope Rotor 61 8.6 Starter Rope / Grip 61 8.7 Tensioning the Rewind Spring 62 8.8 Replacing the Rewind Spring 63 9. QuickStop Super 73 10.3.1 Switch Lever QuickStop Super 74 10.3.2 Lockout Lever - ... Leakage Test 89 RA_737_00_01_01 MS 231, MS 231 C, MS 251, MS 251 C q © ANDREAS STIHL AG & Co. Specifications 5 2.1 Engine 5 2.2 Fuel System 5 2.3 Ignition System 5 2.4 Chain Lubrication 5 2.5 Tightening Torques 6 3. Troubleshooting 8 3.1 Clutch 8 3.2 Chain Drive, Chain Brake, Chain Tensioner 9 3.3 Chain Lubrication 11 3.4 Rewind Starter...
Instruction Manual
Page 5
... wiped away immediately. Always perform leakage test after removal. do not use original STIHL replacement parts. Do not re-use fuel hoses after working on small parts. Always...nuts and other fasteners in the instruction manual. Preparations for servicing Remove the chain sprocket cover, saw chain and guide bar before re-installing - Always use sharp-edged pliers, screwdrivers... wear or damage before carrying out repairs or mounting the machine to overheating. 4 MS 231, MS 231 C, MS 251, MS 251 C Run the machine only with a knife or similar tool. there is otherwise ...
... wiped away immediately. Always perform leakage test after removal. do not use original STIHL replacement parts. Do not re-use fuel hoses after working on small parts. Always...nuts and other fasteners in the instruction manual. Preparations for servicing Remove the chain sprocket cover, saw chain and guide bar before re-installing - Always use sharp-edged pliers, screwdrivers... wear or damage before carrying out repairs or mounting the machine to overheating. 4 MS 231, MS 231 C, MS 251, MS 251 C Run the machine only with a knife or similar tool. there is otherwise ...
Instruction Manual
Page 9
...new clutch Install new clutch drum Saw chain rotates at idle speed Engine idle speed too high Clutch springs stretched Clutch springs broken Readjust idle speed screw LA Replace the clutch springs or install new clutch Replace the clutch springs Loud noises Clutch ...springs stretched Needle cage damaged Clutch shoe retainer broken Clutch shoes and carrier worn Replace all clutch springs Fit new needle cage Install new retainer or clutch Install new clutch 8 MS 231, MS 231 C, MS 251, MS 251...
...new clutch Install new clutch drum Saw chain rotates at idle speed Engine idle speed too high Clutch springs stretched Clutch springs broken Readjust idle speed screw LA Replace the clutch springs or install new clutch Replace the clutch springs Loud noises Clutch ...springs stretched Needle cage damaged Clutch shoe retainer broken Clutch shoes and carrier worn Replace all clutch springs Fit new needle cage Install new retainer or clutch Install new clutch 8 MS 231, MS 231 C, MS 251, MS 251...
Instruction Manual
Page 10
... idle speed screw LA Replace the clutch springs or install new clutch Replace the clutch springs Saw chain does not stop immediately when brake is activated Brake spring stretched or broken Fit new brake spring Brake band stretched or worn Clutch drum worn Fit new brake band Install new clutch drum MS 231, MS 231 C, MS 251, MS 251 C 9
... idle speed screw LA Replace the clutch springs or install new clutch Replace the clutch springs Saw chain does not stop immediately when brake is activated Brake spring stretched or broken Fit new brake spring Brake band stretched or worn Clutch drum worn Fit new brake band Install new clutch drum MS 231, MS 231 C, MS 251, MS 251 C 9
Instruction Manual
Page 12
... intake hose and pickup or intake hose ruptured 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 Oil suction hose connection damaged Engine housing cracked Install... Install new engine housing Oil pump delivers insufficient oil Oil pump damaged or worn Worm driver is loose Install new oil pump Install new worm MS 231, MS 231 C, MS 251, MS 251 C 11 3.3 Chain Lubrication In the event of faults before disassembling the oil pump.
... intake hose and pickup or intake hose ruptured 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 Oil suction hose connection damaged Engine housing cracked Install... Install new engine housing Oil pump delivers insufficient oil Oil pump damaged or worn Worm driver is loose Install new oil pump Install new worm MS 231, MS 231 C, MS 251, MS 251 C 11 3.3 Chain Lubrication In the event of faults before disassembling the oil pump.
Instruction Manual
Page 17
... throttle shutter completely closed Tank vent faulty Clean the carburetor Reset low speed screw (L) correctly Reset idle speed screw (LA) correctly Replace tank vent Saw chain rotates at idle speed Leak on fuel hose from tank to carburetor Seal connections or install new fuel hose Engine idle speed too... high Readjust with idle speed screw LA (counterclockwise) Clutch springs stretched or fatigued Replace the clutch springs or install new clutch Clutch spring hooks broken Replace the clutch springs 16 MS 231, MS 231 C, MS 251, MS 251 C
... throttle shutter completely closed Tank vent faulty Clean the carburetor Reset low speed screw (L) correctly Reset idle speed screw (LA) correctly Replace tank vent Saw chain rotates at idle speed Leak on fuel hose from tank to carburetor Seal connections or install new fuel hose Engine idle speed too... high Readjust with idle speed screw LA (counterclockwise) Clutch springs stretched or fatigued Replace the clutch springs or install new clutch Clutch spring hooks broken Replace the clutch springs 16 MS 231, MS 231 C, MS 251, MS 251 C
Instruction Manual
Page 25
... 2310RA033 TG 1 : Take the brake lever (2) out of the flat spring (1) into its seat (arrow) as far as stop. 2310RA020 TG 24 MS 231, MS 231 C, MS 251, MS 251 C Remove the brake spring (1) from the anchor pin (arrow). : Disconnect the brake cable (1). - Remove the shroud, b 6.4 - Clean the pivot... 1 1 : Disconnect the spring (1) from the brake lever. 2 2310RA034 TG Installing - 2310RA035 TG 5.4 Brake Lever on the hand guard and replace the hand 1 guard if necessary. Troubleshooting, b 3.2 - Remove the brake spring from the anchor pin (arrow). - Engage the...
... 2310RA033 TG 1 : Take the brake lever (2) out of the flat spring (1) into its seat (arrow) as far as stop. 2310RA020 TG 24 MS 231, MS 231 C, MS 251, MS 251 C Remove the brake spring (1) from the anchor pin (arrow). : Disconnect the brake cable (1). - Remove the shroud, b 6.4 - Clean the pivot... 1 1 : Disconnect the spring (1) from the brake lever. 2 2310RA034 TG Installing - 2310RA035 TG 5.4 Brake Lever on the hand guard and replace the hand 1 guard if necessary. Troubleshooting, b 3.2 - Remove the brake spring from the anchor pin (arrow). - Engage the...
Instruction Manual
Page 27
..., MS 231 C, MS 251, MS 251 C Free travel must be relaxed when the lockout lever is released. : Carefully press the lockout lever (1) to disconnect the brake spring (1) from the anchor pin (arrow). - Press down the lockout lever (1) and hold it in hand guard, b 14 - Remove the chain brake cover, b... 5.2 The brake cable must be depressed without the brake lever moving. If this is not the case, replace the brake spring. - 2 1 1 TOP 1 2310RA042 TG 2310RA031 TG 2310RA044 TG TOP : ...
..., MS 231 C, MS 251, MS 251 C Free travel must be relaxed when the lockout lever is released. : Carefully press the lockout lever (1) to disconnect the brake spring (1) from the anchor pin (arrow). - Press down the lockout lever (1) and hold it in hand guard, b 14 - Remove the chain brake cover, b... 5.2 The brake cable must be depressed without the brake lever moving. If this is not the case, replace the brake spring. - 2 1 1 TOP 1 2310RA042 TG 2310RA031 TG 2310RA044 TG TOP : ...
Instruction Manual
Page 31
...chain catcher (arrow) is installed in the reverse sequence. 1 : Position the replacement chain catcher (1) so that it lines up with STIHL multipurpose grease, b 14 - If the chain catcher is damaged or worn, install a replacement chain catcher. 2310RA045 TG 5.5.1 Quick Chain Tensioner The quick chain...screw (arrow). : Remove the cover plate (1) and adjusting wheel (2). Check the wing nut (1) and replace if necessary 30 MS 231, MS 231 C, MS 251, MS 251 C Remove the chain sprocket cover. 165RA007 TG 533RA058 TG 2310RA048 TG 1 3 : Inspect the cover (1), spur gear set ...
...chain catcher (arrow) is installed in the reverse sequence. 1 : Position the replacement chain catcher (1) so that it lines up with STIHL multipurpose grease, b 14 - If the chain catcher is damaged or worn, install a replacement chain catcher. 2310RA045 TG 5.5.1 Quick Chain Tensioner The quick chain...screw (arrow). : Remove the cover plate (1) and adjusting wheel (2). Check the wing nut (1) and replace if necessary 30 MS 231, MS 231 C, MS 251, MS 251 C Remove the chain sprocket cover. 165RA007 TG 533RA058 TG 2310RA048 TG 1 3 : Inspect the cover (1), spur gear set ...
Instruction Manual
Page 79
... : Use hook (2) 5910 893 8800 to re-position it and replace if necessary. - Pull off the pickup body (1), check it . - Push the oil suction hose (1), pickup body first, through the housing bore (arrow). 78 MS 231, MS 231 C, MS 251, MS 251 C Open the oil tank cap and drain the oil tank. 1...11. Reassemble all other parts in a clean container, b 1 - Clean the oil tank if necessary, b1 : Line up the oil suction hose (1) - Chain Lubrication 11.1 Pickup Body 11.2 Oil Suction Hose Impurities gradually clog the fine pores of the filter with the pickup body. - This prevents the oil...
... : Use hook (2) 5910 893 8800 to re-position it and replace if necessary. - Pull off the pickup body (1), check it . - Push the oil suction hose (1), pickup body first, through the housing bore (arrow). 78 MS 231, MS 231 C, MS 251, MS 251 C Open the oil tank cap and drain the oil tank. 1...11. Reassemble all other parts in a clean container, b 1 - Clean the oil tank if necessary, b1 : Line up the oil suction hose (1) - Chain Lubrication 11.1 Pickup Body 11.2 Oil Suction Hose Impurities gradually clog the fine pores of the filter with the pickup body. - This prevents the oil...
Instruction Manual
Page 96
...; 200 rpm. 14 12 0 10 8 4 6 2310RA283 TG If this is the basic setting. - Check chain tension and adjust if necessary. - Adjust idle speed with step 1. 3. MS 231, MS 231 C, MS 251, MS 251 C 95 Use the idle speed screw (LA) to set the engine's maximum speed to 13,000 rpm. (...damage. 2310RA284 TG 1. this speed is higher than 3,700 rpm, abort the procedure and start again with a tachometer. Check the air filter and clean or replace if necessary, b 12.1 1 2 : Starting with the high speed screw H (1) against its seat, open it 1 1/2 turns counterclockwise - Use the ...
...; 200 rpm. 14 12 0 10 8 4 6 2310RA283 TG If this is the basic setting. - Check chain tension and adjust if necessary. - Adjust idle speed with step 1. 3. MS 231, MS 231 C, MS 251, MS 251 C 95 Use the idle speed screw (LA) to set the engine's maximum speed to 13,000 rpm. (...damage. 2310RA284 TG 1. this speed is higher than 3,700 rpm, abort the procedure and start again with a tachometer. Check the air filter and clean or replace if necessary, b 12.1 1 2 : Starting with the high speed screw H (1) against its seat, open it 1 1/2 turns counterclockwise - Use the ...
Instruction Manual
Page 97
... 3.6 - Turn the high speed screw (H) slowly counterclockwise as far as a result of lack of lubrication and overheating. 96 MS 231, MS 231 C, MS 251, MS 251 C It is not satisfactory when operating at high altitude. - Even minor adjustments can noticeably affect engine running behavior: The engine...idle speed screw (LA) counterclockwise until the engine runs and accelerates smoothly. Check chain tension and adjust if necessary. - Shut off the engine. - Check the air filter and clean or replace if necessary, b 12.1 Standard setting - Erratic idling behavior, poor acceleration (...
... 3.6 - Turn the high speed screw (H) slowly counterclockwise as far as a result of lack of lubrication and overheating. 96 MS 231, MS 231 C, MS 251, MS 251 C It is not satisfactory when operating at high altitude. - Even minor adjustments can noticeably affect engine running behavior: The engine...idle speed screw (LA) counterclockwise until the engine runs and accelerates smoothly. Check chain tension and adjust if necessary. - Shut off the engine. - Check the air filter and clean or replace if necessary, b 12.1 Standard setting - Erratic idling behavior, poor acceleration (...