Cylinder bore mm/ inches 44 / 1,73" 44 / 1,73" 40 / 1,57" 42 / 1,65" 42 / 1,65" 45 / 1,77" 46 / 1,81" 47 / 1,85"
Stroke mm/inches 32,5 / 1,28" 32,5 / 1,28" 32,5 / 1,28" 32,5 / 1,28" 32,5 / 1,28" 32,5 / 1,28" 34,0 / 1,34" 34,0 / 1,34"
Max power/speed kW/hp/rpm 2,3/ 3,1 /2,3/ 3,1 /2,0 / 2,7 / 2,2 / 3,0 / 2,5 / 3,4 / 2,4 / 3,3 / 3,2 / 4,35 / 3,0 / 4,1 / 9 000

CS 2149/W:

Spark plug gap mm/inches 0,5 / 0,02"

Ignition system SEM CD

Air gap mm/inches 0,3 / 0,012"
Carburettor type ZAMA C3-EL17 (EPA) ZAMA C3-EL18 Walbro HDA 195 (EPA) ZAMA C3-EL18 ZAMA C3-EL 17 ZAMA C3-EL17 (EPA) ZAMA C3-EL18 Walbro HDA 198 (EPA) Walbro HDA 199 Walbro HDA 198/190 (H) (EPA) Walbro HDA 199/191 (H)
CS 2141/CS 2145/ CS 2150: 0,5 / 0,02" CS 2147/C/W/H: 0,5 / 0,02" CS 2152/C/W/H: 0,5 / 0,02" CS 2156/C/W/H: 0,5 / 0,02" CS 2159/C/W/H: 0,5 / 0,02"
SEM CD SEM CD SEM CD SEM CD SEM CD
0,3 / 0,012" 0,3 / 0,012" 0,3 / 0,012" 0,3 / 0,012" 0,3 / 0,012"
Effective cutting length Chain speed at cm/inches max power revs m/s rpm CS 2149/W: 30-48 / 12"-19" 17,3 / CS 2141/CS 2145/ CS 2150: 30-43 / 12"-17" 17,3 / CS 2147/C/W/H: 30-48 / 12"-19" 18,5 / CS 2152/C/W/H 30-48 / 12"-19" 17,3 / CS 2156/C/W/H: 30-48 / 12"-19" 21,4 / CS 2159/C/W/H: 31-48 / 12"-19" 8 English 20 / 9 000
Chain pitch mm/inches 8,25 / 0,325" 8,25 / 0,325" 8,25 / 0,325" 8,25 / 0,325" 8,25 / 0,325" 9,52 / 3/8" 8,25 / 0,325" 9,52 / 3/8"
Drive link mm/inches 1,3 / 0,050" - 1,5 / 0,058" 1,3 / 0,050" - 1,5 / 0,058" 1,3 / 0,050" - 1,5 / 0,058" 1,3 / 0,050" - 1,5 / 0,058" 1,5 / 0,058" 1,5 / 0,058"
Idling speed rpm CS 2149/W: CS 2141/CS 2145/ CS 2150: CS 2147/C/W/H: CS 2152/C/W/H: CS 2156/C/W/H: CS 2159/C/W/H: Engagement speed rpm Max. speed rpm / / Spark plug NGK BPMR 7A, Champion RCJ 7Y NGK BPMR 7A, Champion RCJ 7Y NGK BPMR 7A, Champion RCJ 7Y NGK BPMR 7A, Champion RCJ 7Y NGK BPMR 7A, Champion RCJ 7Y NGK BPMR 7A, Champion RCJ 7Y
Fuel tank capacity Litres/US pints CS 2149/W: 0,5 / 1,06 CS 2141/CS 2145/ CS 2150: 0,5 / 1,06 CS 2147/C/W/H: 0,5 / 1,06 CS 2152/C/W/H: 0,5 / 1,06 CS 2156/C/W/H: 0,68 / 1,43 CS 2159/C/W/H: 0,68 / 1,43

Carefully prise the carburettor assembly off the lefthand rubber mounting using a small screwdriver. 4
Carefully prise the stop switchs upper mounting off the air lter holder while lifting the switch to release it from the lower mounting.

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Stop switch retting

Choke control removal

1 Remove the cylinder cover, air lter and stop switch. Disconnect the fuel hose from the carburettor. NOTE! Do not use knurled pliers to disconnect or reconnect the fuel hose. This could damage the hose and lead to leakage or fracture.
2 Carefully press the new stop switch into place. Check that the switchs upper mounting clips over the air lter holder. 2
Disconnect the pushrod from the carburettor by rst carefully prising up the spring over the end of the rod, where it connects to the throttle lever (A). Then press the throttle lever forwards (B) while pressing the throttle pushrod backwards (C) and lifting it off the lever. Withdraw the throttle pushrod from the tank and lift it upwards without pulling it through the rubber inlet manifold. Carefully release the carburettor assembly from the right-hand rubber mounting and lift it upwards. Ret the stop plate. Engage the stop plate in the front slot rst then lift the rear edge onto the stop switch. Slide the stop plate in as far as it will go. 3 Ret: the leads to the stop plate and stop switch air lter cylinder 3
Compress the clip that holds the choke control to the carburettor while pulling it out at the same time. Disconnect the choke control from the air lter holder.

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Choke control retting
First reattach the choke control to the air lter, then press it onto the carburettor so that the clips engage. Then ret: stop switch carburettor into its rubber mountings throttle pushrod into the fuel tank and connect to throttle lever. lift the spring arm over the throttle pushrod fuel hose to the carburettor air lter and cylinder cover
Clean and inspect all parts carefully. If there are any cracks or other defects replace the damaged parts with new ones. Always use original parts. Lubricate the throttle lock with oil. Check that the spring is not broken and has not lost its tension.
Throttle lock, throttle trigger and return spring retting
Throttle lock, throttle trigger and return spring removal
Ret the return spring to the throttle trigger as shown. Make sure the spring is correctly positioned by engaging one end in the slot in the throttle trigger (A). 2 First insert the rear edge of the throttle trigger into the tank. Then push/clip the front edge into the two clips on the tank with the aid of a combination tool, for example. Drive in the steel pin from the clutch side. Use a 2.5 mm/0.1" diameter drift.

Remove the throttle lock by pressing it to the left (A) and carefully levering it up with a screwdriver on the clutch side (B) of the saw to disengage the lugs on either side of the throttle lock from the fuel tank. When both lugs are clear of the tank, pull the lock backwards (C). 2
Drive out the steel pin using a 2.5 mm/0.1" diameter drift (A). Push it out from the ywheel side of the saw. Remove the throttle trigger by rst pressing it towards the clutch side of the saw (B) until it clicks, then towards the ywheel side until it clicks again. Remove it from the tank and lift out the return spring.
3 Then press down the return spring while pressing the throttle lock forwards/upwards into the retaining clip in the fuel tank until you hear a click. Release the return spring in the throttle lock, then press the lock down onto the tank. 4 Check the operation of the throttle lock by trying to press the throttle trigger without pressing down the throttle lock. Also check that the throttle lock and throttle trigger return freely to their original positions when released.

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Hand grip heater on model CS 2147 W, CS 2149 W, CS 2152 W, CS 2156 W, CS 2159 W removal
No heating or heating only in front hand grip Front hand grip troubleshooting 1
2 Reconnect the lead and ret the hand grip cover and cylinder cover. Switch troubleshooting 1 Carefully free the switch and frame from the front hand grip using a screwdriver. 2 Disconnect the leads from the switch and connect a multimeter to it. The meter should read over 1000 ohm when the switch is in the 0 position. The meter should read no higher than 0.1 ohm with the switch in the 1 position. Replace the meter if the readings are outside these limits. Rear hand grip heater not working Rear hand grip heater troubleshooting 1 Remove the cylinder cover, air lter and cover from the rear hand grip.
Remove the three bolts that secure the cover over the front hand grip. Disconnect the leads from the switch and generator and measure the resistance of the hand grip heater, which should be 34 ohm. Replace the front hand grip if the resistance is higher. 2
2 Disconnect the red lead from the heater and connect a multimeter between it and the black earth lead that is bolted to the bottom of the carburettor on the clutch side of the saw. The meter should read 0.71.2 ohm. If the reading is higher replace the heater element. 3 Remove the air lter, throttle pushrod, rubber diaphragm and carburettor, see Carburettor removal. 4 Remove the bolt from the plate at the base of the carburettor to release the lead for the heater element. 5

Position the starter assembly on the crankcase and tighten the bolts to a torque of 2.53.5 Nm.
Remove the cylinder cover. Disconnect the HT lead, remove the spark plug and t piston stop 15-01 in its place. Take off the starter assembly, release the leads from the cable guide and remove it. Model CS 2149, CS 2152: Remove the cover from the hand grip. 2

Ignition module testing

If there is a fault in the ignition system the ignition module must be tested before the ignition system is removed.
If replacing the ignition module, disconnect its leads and unscrew it. The ignition module can be left in place if you are simply removing the ywheel. 3 Test the ignition module as follows: Connect a test spark plug 13-01 to the ignition lead and clip the test spark plug onto the cylinder. Turn the engine over using the starter cord. If the test spark plug produces a spark the ignition module is OK.
Loosen the ywheel nut using a suitable socket and unscrew it until it is ush with the end of the shaft.

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Repair instructions 4
Replacing the generator, model CS 2147 W, CS 2149 W, CS 2152 W, CS 2156 W, CS 2159 W
1 Remove the cylinder cover. Disconnect the HT lead, remove the spark plug and t piston stop 15-01 in its place. Take off the starter assembly, release the leads from the cable guide and remove it. Remove the cover from the hand grip. 2
Position puller 90-02 over the magnets and counterweight on the ywheel. Tighten 23 turns and tap the head of the puller with a metal mallet to release the ywheel. Remove the puller, nut and washer. Lift off the ywheel.
Clean all parts, especially the tapers on the ywheel and shaft. Check that the ywheel is not cracked or damaged in any other way. Loosen the ywheel nut using a suitable socket and unscrew it until it is ush with the end of the shaft. Position puller 90-02 over the magnets and counterweight on the ywheel. Tighten 23 turns and tap the head of the puller with a metal mallet to release the ywheel. Remove the puller, nut and washer. Lift off the ywheel. 3
Unscrew the two bolts from the generator but leave the generator in place.

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Repair instructions 4 Remove the fuel hose and throttle pushrod from the carburettor. Unbolt the rear tank mounting from the crankcase, i.e. the rear vibration damping spring, and both stops. Lower the tank as far as it will go to allow access to the heater lead where it is connected to the tank. 5 Disconnect the generator lead from the hand grip and unclip it from the tank. Remove the generator and lead.
Ignition module and ywheel retting

Generator retting

1 Feed the generator lead through the holes in the crankcase and hand grip. Bolt the generator in position, tightening the bolts to a torque of 5 Nm. Clip the lead to the tank. NOTE! The lead connector must be positioned on the right of the clip, see diagram. Connect the lead to the connector on the hand grip. 2 Ret: fuel tank with both stops and rear vibration damping spring fuel hose to carburettor, hose length between tank and crankcase: 43 mm/1.69 inches and between crankcase and carburettor: 53 mm/2.09 inches throttle pushrod to carburettor ywheel with nut and washer cable guide, leads and starter assembly Remove the piston stop and reconnect the HT lead and cylinder cover. To ret the ignition module proceed as follows: Turn the ywheel so that the magnets are in line with the ignition module. Fit the ignition module with the plastic feeler gauge (34-01) held in position at the same time, without tightening the bolts. Connect the black earth lead to the front screw on the ignition module. Adjust the gap between the ignition module and magnet to 0.3 +/- 0.1 mm. The gap must be measured at either of the two lowest pegs on the ignition module. Tighten the bolts to 4.56 Nm. Connect the blue lead to the ignition module. Place the ywheel on the crankshaft. Turn the ywheel so that the key lines up with the keyway in the shaft. Fit the washer and nut on the shaft and tighten to a torque of 25-30 Nm. 2

0,3 mm

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Repair instructions 3

Centrifugal clutch removal
1 Remove the cylinder cover. Disengage the chain brake by pushing the kickback guard backwards. Undo the guide bar bolts and remove the clutch cover, chain and guide bar. 2
Then ret: cable guide and press the leads into position HT lead starter assembly, tighten to a torque of 2.53.5 Nm cylinder cover Disconnect the HT lead. Remove the spark plug and t piston stop 15-01 in its place. 3 Models CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152

Unbolt the clutch using tool 16-02 and a suitable socket or combination spanner. Turn the nut clockwise to remove it. Model CS 2156, CS 2159
Use clutch tool 22-English
Repair instructions 4 Models CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152 NOTE! Handle the clutch springs carefully. If they are opened up too much they could damage the saw. Model CS 2156, CS 2159

Min 65 mm

Centrifugal clutch retting
1 Model CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152 NOTE! Handle the clutch springs carefully. If they are opened up too much they could damage the saw.
Carefully prise out the clutch springs with a screwdriver. Model CS 2156, CS 2159

Inspection and cleaning

Clean and inspect all parts carefully. If there are any cracks or other defects replace the damaged parts with new ones. Always use original parts. Models CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152 Insert the clutch springs in the shoes using circlip pliers. Model CS 2156, CS 2159

Min 65mm

Check the thickness of the clutch shoes by using vernier callipers to measure the diameter of the clutch. If the diameter is less than 65 mm the clutch assembly must be replaced. Fit the clutch springs in the shoes using circlip pliers and a screwdriver.

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Repair instructions 2 Models CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152
Oil pump removal CS 2147, CS 2149, CS 2150, CS 2152, CS 2156, CS 2159
1 Empty and clean the oil tank. 2
Fit the clutch onto the crankshaft and tighten anticlockwise as far as it will go. Then tighten to a torque of at least 20 Nm using tool 16-02 and a suitable socket or combination spanner. Model CS 2156, CS 2159
Remove the cylinder cover. Disengage the chain brake by pushing the kickback guard backwards. Undo the guide bar bolts and remove the clutch cover, chain and guide bar. Disconnect the HT lead. Remove the spark plug and t piston stop 15-01 in its place. Unscrew the clutch (clockwise) using clutch tool 16-02 and a suitable socket spanner or combination spanner (use tool 22-02 for model CS 2159). 3 Models CS 2141, CS 2145, CS 2147, CS 2149, CS 2150, CS 2152

D C B A

Fit the clutch and tighten anticlockwise as far as it will go. Then tighten to a torque of at least 20 Nm using tool 22-02. 3 Remove the piston stop. Fit the spark plug, tightening it to a torque of 15 Nm, then connect the HT lead. Then ret: cylinder cover guide bar chain clutch cover Unbolt and remove the clutch drum (A), RIM chain sprocket (B) if tted, needle bearing (C) and pump drive wheel (D).

9 Rell the tank with oil. For more information see the user instructions for this model for the recommended grade of oil.
Oil pump retting CS 2141, CS 2145
Lubricate the piston pump (C) with chain oil and t the pump piston. 2 Fit the pump. A round pin secures its position. Model CS 2156, CS 2159
Push the crankcase up a little from the fuel tank and screw on the lter (A) from underneath.

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Repair instructions 3 Fit the chain guide plate (one bolt), tightening torque 2-3 Nm. NOTE! Check that the chain tensioner is in position. Fit the bolts on the anti-vibration elements. Note. Models CS 2145 and CS 2150 have another type of chain tensioner, which is adjusted from the side. 4 See Oil pump Retting, models CS 2147, CS 2149, CS 2150, CS 2156, CS 2159 pos. 6-9.

Carburettor removal

Adjustable oil pump adjustment CS 2147, CS 2149, CS 2150, CS 2152, CS 2156, CS 2159
Use a screwdriver or adjustable spanner to turn the adjuster screw on the pump. Turning the screw clockwise decreases the oil ow and turning it anticlockwise increases the oil ow. NOTE! Do not use knurled pliers to disconnect or reconnect the fuel hose. This could damage the hose and lead to leakage or fracture. Remove the cylinder and air lter. Disconnect the leads from the stop switch and the fuel hose from the carburettor. 2
Recommended setting: 1315" bar Min. setting 1518" bar Midway setting 1820" bar Max. setting
Disconnect the pushrod from the carburettor by rst carefully prising up the spring over the end of the rod, where it connects to the throttle lever (A). Then press the throttle lever forwards (B) while pressing the throttle pushrod backwards (C) and lifting it off the lever. Withdraw the throttle pushrod from the tank and lift it upwards without pulling it through the rubber inlet manifold. Carefully release the carburettor assembly from the right-hand rubber mounting and lift it upwards.

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Remove the rubber inlet manifold using a large screwdriver. 4
When replacing the thermostat: Disconnect the cable from X and V. Trouble shooting, see page 20. On saws with carburettor CS 2147 H, CS 2149 H, CS 2152 H, CS 2156 H, CS 2159 H Replacing the heating element: Lower the rear section of the tank by removing the bolt between the hand grip cover and vibration damping springs. Remove the starter and then loosen the stop screws on both sides (one is located under the starter and this must be removed rst). Now disconnect the cable from X and Y. Dismantling the carburettor: Loosen the high, low and idling jet screws.
Undo and remove the carburettor bolts. Lift off the carburettor. On saws with a carburettor heater CS 2147 H, CS 2149 H, CS 2152 H, CS 2156 H, CS 2159 H Heating element

Remove the brackets two bolts above the carburettor. Disconnect the cable connections to the carburettor heater and remove the heating element.

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Carburettor dismantling
Clean all the carburettor components in petrol. Use an airline to dry off the petrol from all components. Blow through all the channels in the carburettor body and check that they are not blocked. Check that: The gasket, pump diaphragm and metering diaphragm are undamaged. There is no play in the throttle and choke valves.
The needle valve and its lever arm are not worn. The fuel lter is undamaged. The tips of the high and low speed jet screws are not damaged. The air intake duct is not cracked.

Carburettor reassembly

The item numbers in the diagram refer to the steps below (17). 1 Remove the cover from the metering unit and carefully remove the metering diaphragm and gasket. 2 Undo the screw and take out the needle valve, together with the lever arm, spindle and spring. 3 Remove the cover from the pump unit and carefully remove the gasket and pump diaphragm. 4 Remove the fuel lter. 5 Remove the high, low and idling jet screws. (HDA 159A high and low jet screws are protected by plastic caps which can be prised off with a screwdriver. Only on EPA, see appendix A.) 6 Remove the plug by rst drilling a hole in it and then prising it out with a screwdriver or the like. 7 If necessary remove the throttle and choke valves, and remove the spindles together with the lever arms and springs. 36 English NOTE! Cleanliness is very important when reassembling the carburettor. Tiny particles of dirt can cause operating problems.
The item numbers in the diagram refer to the steps below (18).
Repair instructions 1 If the throttle and choke butteries and their spindles were removed, these must be retted. Lubricate the spindle bearings with light oil. 2 Insert the plug in the hole with the convex side upwards and expand it by pressing downwards with a drift. 3 Ret the high and low speed jet screws and springs, plus the idling screw. Fit the plastic caps over the high and low speed screws. 4 Fit the fuel lter, using the handle of a small screwdriver. 5 Fit the pump diaphragm, gasket and cover to the pump unit. 6

Carburettor pressure testing
Pressure testing should be carried out with the carburettor fully assembled. Testing should always be carried out after the carburettor has been repaired, but can also be performed for troubleshooting before dismantling. Carry out the test as follows: Screw in the high and low speed jet screws and back them off one turn. Connect pressure tester 38-01 to the carburettor fuel inlet.
Lower the carburettor into a beaker of water. Pump up the pressure to 50 kPa (0.5 bar) and clamp the pump tube. There should be no leakage. If leakage occurs, refer to the table below.
Fit the needle valve with lever arm, spindle and spring and tighten the screw. Use a rule to check that the lever arm is level with the cover face. If necessary, the lever arm can be bent slightly. 7 Fit the metering diaphragm with its gasket and ret the cover to the metering unit. 8 Carry out pressure testing.
Leakage Diffuser jets In impulse tube Ventilation hole above metering unit
Fault lies in Needle valve Pump diaphragm Control diaphragm

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Carburettor retting
NOTE! Cleanliness is very important when reassembling the carburettor. Tiny particles of dirt can cause operating problems. 1
Fit the carburettor. Screw in the carburettor bolts directly from behind, without lifting the carburettor assembly. Tighten to a torque of 11.5 Nm. It is important to hold the carburettor ange while tightening the bolts to prevent the inlet manifold from moving. 3 Fit stop plate 17-01 between the carburettor ange and the insulating plate.
On saws with a carburettor heater CS 2147 H, CS 2149 H, CS 2152 H, CS 2156 H, CS 2159 H
Push the rear carburettor mounting into its rubber bushing using a small screwdriver. Remove stop plate 17-01. 4
Insert the heating element between the air lter connection and carburettor as well as above the carburettor. Route the cable as illustrated above. Tighten the bracket above the carburettor with the two bolts. Connect the cables to the carburettor heater.
Connect the fuel hose to the carburettor. Ret the throttle pushrod at the same time as the rubber inlet manifold, press in the throttle pushrod so that it engages in the carburettor and t the spring. 38 English

Repair instructions 5

Carburettor heater CS 2147 H, CS 2149 H, CS 2152 H, CS 2156 H, CS 2159 H Retting

Heating element

Connect the leads to the stop switch.
Carburettor heater CS 2147 H, CS 2149 H, CS 2152 H, CS 2156 H, CS 2159 H Removing

Remove: carburettor 1 Remove the two screws from the clip above the carburettor. 1 Fit the heating element between the air lter connection and the carburettor as well as above the carburettor. 2 Tighten the bracket above the carburettor using the two bolts. 3 Connect the leads to the carburettor heater. Ret: carburettor
2 Disconnect the leads from the carburettor heater and remove the heating element. Heating element

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Air intake system removal
The air intake system comprises: inlet manifold insulating plate with clip carburettor ange impulse hose support ring 1 Remove: cylinder cover air lter carburettor HT lead starter assembly (CS 2141, CS 2145) Fuel tank (CS 2141, CS 2145) 2
Unscrew and remove the bolt from the silencer support. 4
Unscrew the four cylinder bolts. Lift up the cylinder so that the intake system insulating plate is free of the crankcase.
Unbolt the vibration damping spring between the cylinder and hand grip.
On models CS 2141 and CS 2145 there are cylinder bolts on the underside.

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Air intake system retting
Fit the inlet manifold (A) through the insulating plate in the carburettor ange cut-out (B), and check that the insulating plates impulse tube sits correctly in the inlet manifold. Fit the perforated brass support ring in the inlet manifold. Free the insulating plate from the cylinder by releasing the clamp using pliers. Remove the complete air intake system. 6 Remove: support ring carburettor ange from the inlet manifold insulating plate 2
Clean and inspect all parts carefully. If there are any cracks or other defects replace the damaged parts with new ones. Always use original parts. NOTE! When replacing the impulse hose it must not be lubricated with oil or grease.
Fit the air intake system on the cylinder and snap the insulating plate into position. Check carefully that the impulse tube is correctly seated against the cylinders impulse channel. 3
Position tool 17-01 between the carburettor ange and the insulating plate.

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Carburettor adjustment
For instructions on adjusting the EPA carburettor see appendix A. Adjusting the carburettor involves adjusting the engine to the local conditions e.g. climate, altitude, fuel and type of two-stroke oil. The carburettor is equipped with three adjustment options. L = Low speed jet H = High speed jet T = Idling adjustment screw
Ret the carburettor. Screw in the carburettor bolts directly from behind without lifting the carburettor assembly, tightening to a torque of 11.5 Nm. It is important to hold the carburettor ange securely when tightening the bolts to prevent the inlet manifold from moving. 4
The L and H jets adjust the fuel ow to match the airow that the throttle valve opening allows. Turning them clockwise makes the fuel/air mixture weaker (less fuel in relation to the amount of air) and turning them anti-clockwise makes the fuel/ air mixture richer. A weak mixture increases the engine speed and a rich mixture decreases the engine speed. The T screw controls the throttle position when idling. Turning the T screw clockwise gives faster idling; turning it anti-clockwise lowers idling speed. WARNING! The guide bar, chain and clutch cover must be tted before the saw is started, otherwise the clutch may y off and cause injury. Basic settings and running in During testing at the factory the carburettor is adjusted to the basic factory settings. The factory settings are H = 1 turn and L = 1 turn. To ensure that engine components receive adequate lubrication (running in) the carburettor should be set to a somewhat richer fuel mixture for the chainsaws rst 3-4 running hours. This is done by adjusting the maximum speed to 6700 rpm less than the recommended maximum speed.

Push down the rear carburettor mounting into the rubber bushings using a small screwdriver. Remove tool 17-01. 5 Ret: cylinder, see special instructions silencer support (does not apply to CS 2141, CS 2145, CS 2150) air lter HT lead cylinder cover after the test run retighten the silencer bolts to a torque of 810 Nm

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Repair instructions If it is not possible to check the maximum speed with a tachometer then the H jet should not be set to a weaker mixture than the basic factory setting. The recommended maximum speed must not be exceeded. NOTE! If the chain turns at idling speed, the T screw should be turned anti-clockwise until the chain stops. Fine adjustment Once the chainsaw is run in the carburettor should be readjusted. First adjust the L jet screw, then the idling screw T and nally the H jet screw. The recommended engine speeds are as follows: Model CS 2141 CS 2145 CS 2147 CS 2149 CS 2150 CS 2152 CS 2156 CS 2159 Max revs 12,500 rpm 12,500 rpm 14,200 rpm 13,000 rpm 13,000 rpm 13,000 rpm 14,000 rpm 13,500 rpm Idle revs 2,700 rpm 2,700 rpm 2,700 rpm 2,700 rpm 2,700 rpm 2,700 rpm 2,700 rpm 2,700 rpm Fine adjustment of idling speed T The idling speed is adjusted using the screw marked T. If adjustment is necessary, screw in the idling screw T until the chain starts to turn. Then screw it out until the chain stops moving. The idling speed is correctly set when the engine runs smoothly in all positions and there is a clear margin to the speed at which the chain starts to move. High speed jet H The high speed jet H inuences the saw power output and engine speed. If the H jet is set too weak the saw will over-rev, which could cause engine damage. Run the saw at full throttle for about 10 seconds. H=1. Then screw out the H screw 1/4 turn. H=1 1/4. Run the saw again at full throttle for about 10 seconds and listen to the difference in the engine note. Repeat this procedure again with the H screw screwed out another 1/4 turn. H=1 1/2. You have now run the saw at settings H 0, H = +1/4 and H = +1/2 from the factory setting. At full throttle the engine will sound different at each setting. The H screw is correctly adjusted when the saw burbles a little at full throttle without any load. If there is a lot of smoke from the silencer and the saw does not run smoothly then the setting is too rich. Screw in the H screw to the setting that sounds right. NOTE! For optimum adjustment, a tachometer should be used. The recommended maximum speed should not be exceeded. Carburettor correct adjustment When the carburettor is correctly adjusted the saw should accelerate without hesitation and the engine will burble a little at full throttle without any load. The chain must not turn when idling. If the L screw is set too weak this can make the saw difcult to start and cause poor acceleration. If the H screw is set too weak the saw will produce less power, poor acceleration and there is a risk of engine damage. If either the L or H screws are set too rich it will cause acceleration problems or too low working speed.

Use gauge 37-01 to measure vacuum. Readings should be as follows: the vacuum should increase from 30 to 15 within 30 seconds. If readings are outside this range the vyon plugs must be replaced.

Fuel tank retting

1 Insert the fuel hose into the carburettor chamber. Ret the fuel tank. 2
Bolt the front vibration damping spring into position, followed by both stops and the remaining two vibration damping springs. Tighten to a torque of 23 Nm. Check that both vibration damping springs and the stops are correctly seated on the crankcase. Incorrect tting may result in higher vibration levels.

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Piston and cylinder removal
1 Remove: cylinder cover carburettor (see Carburettor removal) silencer spark plug fuel tank (applies to CS 2141, CS 2145)
Fit the throttle pushrod in the tank and connect it to the carburettor. Ret the spring. 4
Connect the fuel hose to the carburettor. Check that the hose is not kinked or too long to be clamped between the crankcase and tank. The correct hose length between the tank and crankcase is 43 mm (1.69 inches). The correct hose length between the crankcase and carburettor is 53 mm (2.09 inches) excluding the mitred section. 5
Unbolt the vibration damping spring from the hand grip. 3
Undo the four cylinder bolts and lift the cylinder off carefully. Models CS 2141, CS 2145
Connect the fuel hose to the carburettor. 6 Then ret: cable guide starter assembly (2.53 Nm) chain and guide bar clutch cover air lter cylinder cover 46 English
Undo the four cylinder bolts from the underside and lift the cylinder off carefully.
Repair instructions 4 Cover the opening in the crankcase. 5 8
When replacing the cylinder CS 2141, CS 2145: Unscrew the decompression valve. (CS 2145) Remove the intake system, see Air intake system removal. Remove the circlips from the ends of the gudgeon pin and press it out. Then lift off the piston. 6 Model CS 2150 is tted with a spacer, which is secured using four bolts from the underside. The spacer does not however need to be removed when removing the cylinder.
Remove the bearing from the little end of the connecting rod. 7 Clean all the components, scraping off all traces of old gasket and carbon from the following places: Piston crown Top of the cylinder bore Cylinder exhaust port Decompression valve channel (CS 2145, CS 2149, CS 2150, CS 2152) Cylinder base and/or crankcase Check the following: The surface coating of the cylinder is not worn through, especially in the upper part of the cylinder. If replacing the cylinder: Unscrew the decompression valve. Remove the intake system, see Air intake system removal. The cylinder is free from score marks and areas of wear. The piston is free from score marks. Small scratches can be polished out with ne emery paper. The piston ring is not burnt into its groove.

English 47

Piston and cylinder retting CS 2147, CS 2149, CS 2150, CS 2152, CS 2156, CS 2159

Crankshaft complete CS 2141, CS 2145, CS 2150 reassembly
Place the ywheel side of the crankcase over the crankshaft and pull the two crankcase halves together using assembly tools 30-16. 4
1 Fit the crankshaft complete in the crankcase. Fit and tighten the six crankcase bolts to a torque of 810 Nm. Check that the crankshaft rotates freely. 5 Ret the following parts: bark rest, 8-10 Nm oil pump, 3-4 Nm, see Oil pump - retting chain tensioner centrifugal clutch, min 20 Nm, see Centrifugal clutch - retting fuel tank, see Fuel tank - retting piston and cylinder, see Piston and cylinder - retting generator, see Replacing the generator carburettor base, 3-4 Nm carburettor, 1-1,5 Nm, see Carburettor - retting throttle pushrod silencer, 12-14 Nm, see Silencer - retting CS 2150: Fit and tighten the four bolts holding the spacer from underneath and t the crankshaft complete in the crankcase. Ret the following parts: piston and cylinder* fuel tank* silencer* carburettor* throttle pushrod centrifugal clutch* generator* ignition system* starter assembly* cylinder cover clutch cover chain and bar * See special instructions.

English 55

Repairing damaged threads
A repair kit, 33-01, is available for repairing damaged threads. First drill out the hole using: 6.1 mm drill bit for magnesium crankcase Then screw in the thread insert using a suitable bolt and spanner.
Guide bar bolts replacement
1 Drain the oil tank. 2 Knock through the old guide bar bolt so that it falls into the oil tank. 3 Remove the bolt from the oil tank. 4

Thread insert

A damaged thread can be repaired using a thread insert. The slotted part of the thread insert is screwed in rst, as this is the cutting part. To repair a thread that was originally designed for a PL5 screw: rst drill out with a 6.1 mm diameter drill bit, then screw in the thread insert using a suitable screw and spanner. To repair a thread that was originally designed for a MT6 screw: rst drill out with a 7.1 mm diameter drill bit, then screw in the thread insert using a suitable screw and spanner. This type of thread insert is best suited for use in plastic and magnesium, but not for repairing threads in aluminium. In that case use a helicoil insert with metric screw. New part no. 39-27 40-01 Description PL5 MT6 Fasten a steel wire to the thread of the new bolt, feed the steel wire into the oil tank and out through the bolt hole in the crankcase. 5 Pull the steel wire until the bolt comes out through its hole. 6 Pull through the bolt with its nut. Place a spacer between the nut and crankcase. 7 Check that the square shoulder of the bolt is correctly seated in the recess in the crankcase. 8 Rell with chain oil.