Husqvarna HS 139A Workshop Manual Download Page 40

Page: 40 / 48

Increase and de-

crease engine speed

Cause

Solution

The engine speed

cannot be increased.

The fuel filter is blocked.

Clean the fuel filter. Replace the fuel filter if it

is necessary.

The fuel hose is blocked.

Clean the fuel hose. Replace the fuel hose if

it is necessary.

There is air in the fuel pipe.

Use the air purge bulb to remove the air from

the fuel hose.

There is vacuum leakage.

Examine the pump diaphragm and the pump

diaphragm gasket for wear and damages.

Replace defective parts. Refer to

Standard di-

mensions and wear limits on page 45.

The vacuum pipe is blocked.

Clean the vacuum pipe.

The screws on the pump cover are loose.

Tighten the screws on the pump cover.

The pump diaphragm is defective.

Replace the pump diaphragm.

The needle valve is defective.

Replace the needle valve.

The carburetor is not installed correctly.

Install the carburetor correctly. Refer to

To re-

move and install the carburetor HS 166A on

page 23.

The heat insulation seal is defective.

Replace the heat insulation seal.

The needle valve lever is damaged.

Replace the needle valve lever.

The needle valve lever is too low.

Adjust the needle valve lever.

The needle valve lever does not operate cor-

rectly.

Examine the needle valve lever. Replace the

needle valve lever if it is necessary.

The needle valve spring is not installed cor-

rectly.

Install the needle valve spring correctly. Refer

To assemble the carburetor on page 27.

The control diaphragm is damaged.

Replace the control diaphragm.

The needle valve is blocked.

Clean the needle valve.

The engine stops

when the engine

speed is decreased.

The pump diaphragm is defective.

Replace the pump diaphragm.

The needle valve lever is too high.

Adjust the needle valve lever.

The needle valve lever does not operate cor-

rectly.

Examine the needle valve lever. Replace the

needle valve lever if it is necessary.

The needle valve is worn.

Replace the needle valve.

There is an object in the needle valve.

Clean the needle valve.

The engine speed

cannot be decreased.

Incorrect adjustment of the governor.

Adjust the governor.

Incorrect position of the throttle.

Adjust the position of the throttle.

The slider of the governor is damaged.

Replace the governor.

40 - Troubleshooting

1425 - 001 - 03.06.2020

Summary of Contents for HS 139A

Page 1: ...Workshop manual HS 139A HS 166A English 1425 001 03 06 2020 ...

Page 2: ...he engine oil 7 4 Servicing data 5 Function overview 5 1 Product overview 13 5 2 Product overview 14 5 3 Serial numbers on the product 15 6 Repair instructions 6 1 To clean and examine the product parts 16 6 2 Starter 16 6 3 Air filter 20 6 4 Carburetor 21 6 5 Carburetor 22 6 6 Muffler 29 6 7 Ignition system 30 6 8 Fuel tank 31 6 9 Flywheel 33 6 10 Crankcase 33 6 11 Function test 37 7 Troubleshoot...

Page 3: ...on the product must read and understand the manual 1 4 Revisions Changes to the product can cause changes to the maintenance work and spare parts Separate information is sent out for each change Read the manual together with all received information about changes to maintenance and spare parts for the product 1 5 Safety WARNING All personnel that repair or do servicing on the product must read and...

Page 4: ...is sufficient Do not remove the fuel tank cap or fill the fuel tank when the engine is on Let the engine become cool before you refuel Do not fill fuel in an indoor area Not sufficient airflow can cause injury or death because of asphyxiation or carbon monoxide Do not smoke near the fuel or the engine Do not put hot objects near the fuel or the engine Do not fill fuel near sparks or flames Before ...

Page 5: ... odourless poisonous and very dangerous gas Do not start the engine indoors or in closed spaces Hot surface Fill the engine with oil before you start the product Note Other symbols decals on the product refer to certification requirements for some commercial areas 1425 001 03 06 2020 Safety 5 ...

Page 6: ... Replace the spark plug if it is necessary X Do a check of all cables and connections X Make sure that the bevel gear is filled with grease X Examine the flywheel brake pad X Clean the spark arrestor screen optional equipment Replace the spark arrestor screen if it is necessary X Examine the idle speed Adjust if it is necessary X Examine and adjust the valve play X Clean the combustion chamber X E...

Page 7: ... do a check of the oil level again 3 4 To replace the engine oil WARNING Engine oil is very hot directly after the engine is stopped Let the engine become cool before you drain the engine oil If you spill engine oil on your skin clean with soap and water 1 Drain the fuel tank Refer to To drain the fuel tank on page 31 2 Remove the ignition cable from the spark plug 3 Put a container below the drai...

Page 8: ...4 Servicing data M6 x 60 2 8 12 Nm M6 x 14 3 8 12 Nm M6 2 8 12 Nm M6 6 10 Nm HS 139A 8 Servicing data 1425 001 03 06 2020 ...

Page 9: ...HS 166A M6 x 70 5 2 8 12 Nm M6 x 20 2 8 12 Nm 1425 001 03 06 2020 Servicing data 9 ...

Page 10: ... 72 Stud Bolt 14 mm Special Nut 8 12 Nm Torque 55 65 Nm Torque M6 x 78 2 Stud Bolt 8 12 Nm Torque M6 x 30 1 Bolt 8 12 Nm Torque M6 x 16 5 4 Bolt 8 12 Nm Torque HS 139A 10 Servicing data 1425 001 03 06 2020 ...

Page 11: ...66A M6 x 72 Stud Bolt 14 mm Special Nut 8 12 Nm Torque 55 65 Nm Torque M6 x 78 2 Stud Bolt 8 12 Nm Torque M6 x 22 2 Bolt 8 12 Nm Torque M6 x 16 5 4 Bolt 8 12 Nm Torque 1425 001 03 06 2020 Servicing data 11 ...

Page 12: ...M6 x 25 10 Bolt 8 12 Nm Torque M6 x 26 2 Bolt 11 13 Nm Torque 12 Servicing data 1425 001 03 06 2020 ...

Page 13: ...n overview 5 1 Product overview 2 8 1 3 4 6 7 5 HS 139A 1 Engine shroud 2 Nut 3 Engine cover 4 Flywheel housing 5 Fuel tank cap 6 Fuel tank 7 Fuel tank screws 8 Crankcase 1425 001 03 06 2020 Function overview 13 ...

Page 14: ...5 2 Product overview 2 1 3 4 8 7 5 6 HS 166A 1 Engine shroud 2 Nut 3 Engine cover 4 Flywheel housing 5 Fuel tank cap 6 Fuel tank 7 Fuel tank screws 8 Crankcase 14 Function overview 1425 001 03 06 2020 ...

Page 15: ...5 3 Serial numbers on the product The engine serial number is found on the rear side of the engine 1425 001 03 06 2020 Function overview 15 ...

Page 16: ...dures are necessary Replace damaged or defective parts Always use original spare parts 6 2 Starter 13 12 11 10 8 7 5 3 1 6 4 9 2 HS 166A HS 139A 1 Retainer screw 2 Starter pawl holder 3 Washer 4 Friction spring 5 Starter pawls 6 Return spring 7 Recoil spring 8 Recoil slot 9 Starter pulley 10 Handle 11 Starter rope 12 Engine cover 13 Nuts 16 Repair instructions 1425 001 03 06 2020 ...

Page 17: ... 1 Remove the starter housing 2 Put pressure on the starter pulley with your hand Pull out the starter rope approximately 30 cm and put the starter rope into the notch in the starter pulley 3 Decrease the pressure of your hand Let the starter pulley rotate clockwise slowly to decrease the tension in the recoil spring 4 Remove the screw and the washer Remove the starter pawl holder the friction spr...

Page 18: ...the end of the starter pawls are put into the slot in the starter pulley 7 Attach the retainer screw 8 Pull out the starter rope approximately 30 cm and hold the starter pulley with your hand 9 Put the starter rope in the notch in the starter pulley 10 Wind the starter rope 1 turn counterclockwise around the starter pulley 11 Decrease the pressure of your hand and let the starter pulley rotate clo...

Page 19: ...nd in the rope pulley 8 Attach the starter rope to the starter pulley Install the knot in the dedicated cut out in the starter pulley 3r 9 Tighten the connection fully Make sure that the free end of the starter rope is as short as possible 10 Wind the starter rope 3 turns counterclockwise around the starter pulley 11 Attach the starter rope handle A to the starter rope B A B 12 Pull out the starte...

Page 20: ...ilter 1 Remove the air filter cover and remove the paper filter 2 Hit the filter against a flat surface to make the particles fall off CAUTION Do not use solvent or compressed air to clean the paper filter 3 Put the air filter back Make sure that the air filter fully seals against the air filter holder 4 Put the air filter cover back 6 3 3 To remove and install the air filter holder WARNING Use pr...

Page 21: ...t shield 6 Gasket 7 Insulator 8 Gasket 9 Gasket 10 Carburetor body 11 Float bowl gasket 12 Hinge pin 13 Float 14 Drain plug gasket 15 Drain plug 16 Float bowl 17 Gasket 18 Float bowl screw 19 Governor rod 20 Governor arm 21 Governor spring 22 Governor control 23 Governor bolt 24 Governor arm bolt 25 Governor arm nut 1425 001 03 06 2020 Repair instructions 21 ...

Page 22: ...1 Nut 12 Float bowl gasket 13 Hinge pin 14 Float 15 Float bowl 16 Drain plug gasket 17 Drain plug 18 Float bowl screw 19 Gasket 20 Governor rod 21 Governor arm 22 Governor spring 23 Governor arm bolt 24 Governor arm nut 25 Governor control 26 Governor pin 6 5 1 To remove and install the carburetor HS 139A 1 Remove the air filter Refer to To remove and install the air filter on page 20 2 Put a clam...

Page 23: ...or and related gaskets and insulator 7 Install in the opposite sequence 6 5 2 To remove and install the carburetor HS 166A 1 Remove the air filter Refer to To remove and install the air filter on page 20 2 Put a clamp on the fuel hose 3 Disconnect the fuel hose from the carburetor 4 Disconnect the throttle rod from the throttle shaft 1425 001 03 06 2020 Repair instructions 23 ...

Page 24: ...ft b Lift and remove the throttle rod 5 Lift and remove the throttle shaft and the throttle return spring 6 Disconnect the governor rod from the governor shaft a Rotate the governor rod 90 degrees in the governor shaft 24 Repair instructions 1425 001 03 06 2020 ...

Page 25: ...retor 1 Remove the air filter holder Refer to To remove and install the air filter holder on page 20 2 Clean the external surface of the carburetor Refer to To clean and examine the carburetor on page 26 3 Remove the screw A and the float bowl gasket D B A C 4 Remove all fuel from the float bowl B 5 Remove the hinge pin C and remove the float D and the float needle valve 1425 001 03 06 2020 Repair...

Page 26: ...dle adjustment screw 15 Remove the O ring and the pilot screw 6 5 4 To clean and examine the carburetor 1 Clean all parts in clean gasoline 2 Use compressed air to dry the gasoline Point the air through all channels in the carburetor housing and make sure that the channels are not blocked 3 Examine all parts for damage and wear Replace the parts that show signs of damage 6 5 5 To do a pressure tes...

Page 27: ...e valve seat for wear or damages Replace damaged parts 12 Put the float pin in the holder on the float 13 Put the float on the body of the carburetor 14 Install the hinge pin 15 Install a new gasket on the float bowl 16 Install a new gasket on the screw 17 Install the float bowl with the screw 18 Remove remaining parts of the gasket from the air intake of the carburetor and install a new gasket 19...

Page 28: ...remove and install the air filter on page 20 2 Disconnect the governor rod from the governor shaft a Rotate the governor rod 90 degrees in the governor shaft b Lift and remove the governor rod 3 Remove the governor rod A from the governor arm B A B 4 Remove the governor spring from the governor control and the governor arm 5 Loosen the governor arm nut and remove the governor arm bolt 6 Remove the...

Page 29: ...idle speed Use protective gloves to prevent burn injuries 6 6 2 To clean and examine the muffler WARNING Risk of burn injury or fire The muffler becomes very hot during operation WARNING Risk of fire The exhaust gases are hot and can contain sparks 1 Clean the muffler with a wire brush 2 Clean the muffler cover with a moist cloth 3 Examine the muffler for wear and damage Replace the muffler if it ...

Page 30: ...material on the spark plug electrodes obey these instructions a Make sure that the idle speed is correctly adjusted b Make sure that the fuel mixture is correct c Make sure that the air filter is clean If the spark plug is dirty clean it and make sure that the electrode gap is correct refer to Technical data on page 41 Replace the spark plug if it is necessary 6 7 3 To do a spark test 1 Remove the...

Page 31: ...tion module B A C 7 Connect a multimeter between point C and point A and measure the resistance For the correct value refer to Standard dimensions and wear limits on page 45 If the measured values are not correct replace the ignition module 8 Examine the distance between the flywheel magnet and the ignition module with the air gap gauge For the correct value refer to Standard dimensions and wear l...

Page 32: ...e fuel hose from the carburetor and connect it to the pressure tester 3 Tighten the fuel tank cap fully 4 Increase the negative pressure in the tank If the negative pressure holds replace the fuel tank cap 6 8 5 To replace the fuel filter All models do not have a fuel filter 1 Compress the fuel tank hose to prevent leakage 2 Pull out the filter through the opening in the fuel tank 3 Move the hose ...

Page 33: ...e a container with the oil filler tube pointed down 4 Make sure all oil is drained before you move the product 6 10 2 To fill the crankcase with oil 1 Put the product on a flat surface 2 Remove the oil filler cap 3 Fill the crankcase with oil The oil level must be in between the marks on the dipstick Use the correct type of oil Refer to Technical data on page 41 6 10 3 To disassemble the crankcase...

Page 34: ...s E and the piston pin F 4 Remove the connecting rod G 6 10 5 Assemble the piston and piston connecting rod 1 Install the connecting rod a Align the mark on the piston head with the longer side of the connecting rod 2 Install the piston pin 3 Install the piston rings a Use a pair of nose pliers and put one end of the ring into the piston slot b Push the ring together with the nose pliers and put t...

Page 35: ...l the piston in the cylinder Make sure that the triangle mark on the piston head is in the direction of the carburetor side 3 Install the crankshaft in the crankcase 4 Align the mark on the camshaft sprocket with the mark on the crankshaft 5 Install the connecting rod as shown in the illustration 6 Install the connecting rod bolt Align the marks on the connecting rods to the lower cap 7 Put the to...

Page 36: ...Technical data on page 41 6 10 8 To disassemble the cylinder valves 1 Disassemble the crankcase Refer to To disassemble the crankcase on page 33 2 Remove the piston and the piston connecting rod Refer to To disassemble the piston and piston connecting rod on page 34 3 Remove the 4 screws on the cylinder head cover 4 Remove the cylinder head cover and the gasket 5 Remove the locknuts 6 Remove the a...

Page 37: ...he cylinder valves into the valve guides 4 Turn the cylinder valves until you can see an approximately 0 8 mm wide matt grey stripe around the valve heads 5 Remove all bearing paste and make sure that the valves are clean before you assemble them 6 11 Function test 6 11 1 To measure engine rpm 1 Start the engine 2 Remove the engine cover 3 Hold the tachometer against the spark plug cap 4 Let the e...

Page 38: ... on page 38 8 Install the cylinder head cover 9 Install the spark plug 6 11 3 To adjust the valve play 1 Hold the rocker arm pivot and loosen the locknut 2 Turn the rocker arm pivot to adjust the clearance 3 Tighten the pivot locknut 4 Measure the clearance between the rocker arms and the valve stems 5 Examine the valve play Refer to To examine the valve play on page 37 38 Repair instructions 1425...

Page 39: ...ncorrect valve play Adjust the valve play The cylinder cover is on correctly attached Tighten the screws on the cylinder cover Damaged combustion chamber Replace the combustion chamber Dirty air filter Clean or replace the air filter Refer to Expired fuel Empty fuel tank and fill with fresh fuel Damaged valve gasket or valve retainer Replace the valve the gasket or the valve re tainer No spark at ...

Page 40: ... needle valve lever is damaged Replace the needle valve lever The needle valve lever is too low Adjust the needle valve lever The needle valve lever does not operate cor rectly Examine the needle valve lever Replace the needle valve lever if it is necessary The needle valve spring is not installed cor rectly Install the needle valve spring correctly Refer to To assemble the carburetor on page 27 T...

Page 41: ...orized magneto Ignition Spark plug Husqvarna HQT 7 Husqvarna HQT 7 Electrode gap mm 0 7 0 8 0 7 0 8 Valve clearance Inlet valve mm 0 10 0 15 0 10 0 15 Exhaust valve mm 0 10 0 20 0 10 0 15 Fuel and lubrication system Fuel tank capacity litre 0 9 1 0 Fuel consumption g kW h 395 395 Oil tank capacity litre 0 5 0 5 Engine oil SAE 10W 30 SAE 10W 30 Weight With empty tanks kg 8 9 9 5 Dimension Without P...

Page 42: ...10 00 9 00 8 00 7 00 6 00 5 00 4 00 2 00 1 00 0 00 3 00 P kW HP Me N m n rpm P kW P HP Me N m HS 139A 5 00 4 50 4 00 3 50 3 00 2 50 2 00 1 00 0 50 0 00 1 50 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 10 00 9 00 8 00 7 00 6 00 5 00 4 00 2 00 1 00 0 00 3 00 P kW HP Me N m n rpm HS 166A 42 Technical data 1425 001 03 06 2020 ...

Page 43: ...13 2 0 1 3XØ8 8 0 1 3 2 53 0 1 23 0 1 49 0 1 Ø25 4 R0 5 R1 5 R7 5 15 80 2 71 8 66 5 46 8 10 3 28 min 33 max 40 2xØ16 A A 2x3 962 0 018 4 763 0 03 0 3 8 24UNF 2B 3 8 24UNF 2B 8 4 0 0 1 Ø22 2 0 0 025 6 6 0 0 1 4 1 0 261 369 345 195 1425 001 03 06 2020 Technical data 43 ...

Page 44: ... 2 0 1 60 0 5 23 0 5 57 7 13 7 80 3 72 0 15 46 8 27 max 32 max 40 10 3 2xØ16 A A Engine Mount Surface 4 1 0 8 5 0 0 1 Ø25 0 0 025 6 3 0 05 0 2x4 763 0 05 0 8 4 0 0 1 3 8 24UNF 2B R05 min 2 340 132 175 391 278 44 Technical data 1425 001 03 06 2020 ...

Page 45: ...ameter 13 002 13 008 mm 0 5118 0 51212 in Inner diameter 13 048 mm 0 5137 in Piston pin Feeler gauge Clearance 0 004 0 016 mm 0 00001 0 0006 in Clearance 0 08 mm 0 0031 in Top piston ring second piston ring Feeler gauge Clearance 0 015 0 045 mm 0 0006 0 0018 in Clearance 0 15 mm 0 006 in Top piston ring Micrometer Width 1 17 mm 0 0460 in Width 1 04 mm 0 0409 in Second piston ring Micrometer Width ...

Page 46: ... 070 mm 0 0020 0 0028 in Clearance 0 120 mm 0 0050 in Valve seat Micrometer Width 0 7 mm 0 028 in Width 2 0 mm 0 08 in Valve spring Micrometer Free length 34 5 mm 1 36 in Free length 33 5 mm 1 32 in Camshaft inlet valve Micrometer Height 27 553 mm 1 085 in Cam height Replace under 27 30 mm 1 075 in Camshaft exhaust valve Micrometer Height 27 701 mm 1 091 in Cam height Replace under 27 40 mm 1 079 ...

Page 47: ...1425 001 03 06 2020 Technical data 47 ...

Page 48: ...1142191 26 2020 06 12 ...

Search results

Summary of Contents for HS 139A

Reviews:

Related manuals for HS 139A

Brands by name

Popular brands

Husqvarna HS 139A, Workshop Manual

Search results

Summary of Contents for HS 139A

Reviews:

Related manuals for HS 139A

Brands by name

Popular brands