background image

42

MS 192 T

Exercise extreme caution while 
carrying out maintenance and repair 
work on the ignition system. The 
high voltages which occur can 
cause serious or fatal accidents.

Troubleshooting on the ignition 
system should always start with the 
spark plug

b

 4.5

– Remove the fan cover, 

b

 9.1.1

The electronic ignition system 
basically consists of an ignition 
module (1) and flywheel (2).

2

1

217RA097 TG

The ignition module accommodates 
all the components required to 
control ignition timing. There are 
two electrical connections on the 
coil body:

:

High-voltage output (1) with 
permanently fitted ignition lead

1 2

217RA325 TG

:

Connector tag (2) for the short 
circuit wire.

Testing in the workshop is limited to 
a spark test. A new ignition module 
with ignition lead must be installed if 
no ignition spark is obtained (after 
checking that the wiring and stop 
switch are in good condition), 

b

 9.1.1

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.

:

Take out the screws (arrows) and 
remove the fan housing (1) with 
rewind starter.

217RA087 TG

1

:

Turn the twist lock (arrow) 
anticlockwise to release it and 
remove the carburetor box 
cover (1).

217RA008 TG

1

:

Apply a suitable tool to the tab 
(arrow) to prise the boot off the 
spark plug (1).

1

217RA009 TG

9.

Ignition System

9.1

Ignition Module

9.1.1

Removing and installing

Summary of Contents for ms 192t

Page 1: ...STIH STIHL MS 192 T 2005 02...

Page 2: ...4 8 5 1 Removal 34 8 5 2 Installation 35 8 5 3 Crankshaft Bearing 37 8 6 Piston 39 8 6 1 Removal 39 8 6 2 Installation 39 8 7 Piston rings 41 9 Ignition System 42 9 1 Ignition Module 42 9 1 1 Removing...

Page 3: ...Throttle Shaft Throttle Shutter 80 14 3 7 Accelerator Pump 81 14 3 8 Adjusting screws 82 14 4 Carburetor Adjustment 83 14 4 1 Basic Setting 83 14 4 2 User Setting 84 14 5 Intake Elbow Removing and Ins...

Page 4: ...ts all the 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 text Action to be taken as shown...

Page 5: ...maintenance or repair work Petrol is highly inflammable and can also be explosive under certain conditions Improper handling may result in burns and other serious injuries Do not bring any fire flame...

Page 6: ...rpm Crankcase leakage test at gauge pressure 0 5 bar under vacuum 0 5 bar 3 2 Fuel System Carburetor leakage test at gauge pressure 0 8 bar Operation of tank vent at gauge pressure 0 3 bar Fuel as spe...

Page 7: ...M 5 Filter base handle housing 1st stage aluminium 1 5 Nut M 5 Filter base handle housing 1st stage 2 0 Nut M 5 Filter base handle housing 2nd stage aluminium 2 5 Nut M 5 Filter base handle housing 2...

Page 8: ...e and rotate it anticlockwise 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 no...

Page 9: ...le speed Idle speed too high Readjust with idle speed screw LA anticlockwise Clutch springs stretched or fatigued Replace clutch springs or install new clutch Clutch spring hooks broken Replace clutch...

Page 10: ...tall new clutch Clutch drum badly worn Install new clutch drum Brake band stuck Check freedom of movement and function of brake band Saw chain rotates at idle speed Idle speed too high Readjust with i...

Page 11: ...l inlet hole in guide bar is blocked Clean oil inlet hole Intake hose or pick up body clogged or intake hose ruptured Fit new intake hose and pick up body Valve in oil tank blocked Clean or replace va...

Page 12: ...rewind spring and increase tension Very dirty or corroded Clean or replace rewind spring Starter rope cannot be pulled out far enough Rewind spring overtensioned Check rewind spring and reduce tension...

Page 13: ...ect air gap between ignition module and flywheel Set air gap correctly Flywheel cracked or has other damage or pole shoes have turned blue Install new flywheel Ignition timing wrong flywheel out of ad...

Page 14: ...resses constantly against the inlet control lever Fit a new metering diaphragm Poor acceleration Idle jet too lean Turn low speed screw L anticlockwise richer until engine accelerates smoothly Main je...

Page 15: ...peed drops quickly under load low power Air filter dirty Clean the air filter Throttle shutter not opened fully Check linkage Tank vent faulty Clean tank vent or replace if necessary Fuel pick up body...

Page 16: ...r replace the crankcase Engine does not deliver full power or runs erratically Piston rings worn or broken Replace piston rings Muffler spark arresting screen carbonized Clean the muffler inlet and ex...

Page 17: ...row and remove the sprocket cover 1 217RA001 TG 1 Slide the guide bar 1 towards the clutch and remove the chain from the guide bar Remove the guide bar 1 Remove the chain 2 via the sprocket 217RA002 T...

Page 18: ...well as its needle bearing Sprocket cover with integrally moulded chain catcher 1 If the chain catcher has broken 2 file down the stub and replace with a replacement chain catcher 3 1 2 217RA350 TG R...

Page 19: ...ws Reassemble remaining parts in reverse order 217RA083 TG Troubleshooting b 4 1 Remove the sprocket cover and bar and chain b 5 1 Release the twist lock arrow Remove carburetor box cover 1 to the rea...

Page 20: ...es over the arms 1 so that the series number 2 is on the same side as the raised hexagon arrow 217RA017 TG 1 2 Clamp the clutch in a vice arrow 217RA018 TG Attach one end of the clutch spring 1 to the...

Page 21: ...le cage 1 from the sprocket Clean the needle cage and crankshaft stub with standard solvent based degreasant not containing any chlorinated or halogenated hydrocarbons 217RA024 TG 1 Examine the sprock...

Page 22: ...e band and clutch drum This in turn reduces the frictional forces and thus prolongs the braking time A fatigued or stretched brake spring has the same negative effect Start the engine With the chain b...

Page 23: ...parts of outside diameter and its remaining thickness is less than 0 6 mm 217RA321 TG Remove the E clip arrow 217RA030 TG Remove the hand guard 2 with lever 1 from the pivot pins Pull the lever out o...

Page 24: ...tool 1 217RA322 TG Wet the knurled area of the new pin 1 with Loctite before fitting it b 16 Position the new pin 1 in the bore so that the knurling on the pin meshes with the existing knurling in th...

Page 25: ...the hand guard is guided past the leaf spring 1 217RA038 TG Coat all sliding and bearing points with STIHL multi purpose grease b 16 Do not grease the brake band Attach the brake band 1 to the brake l...

Page 26: ...n brake b 7 Remove the sprocket cover and bar and chain b 5 1 Troubleshooting b 4 2 Turn the spur gear 2 clockwise until the tensioner slide 1 makes contact on the right and the screw arrow is reveale...

Page 27: ...spur gear together Ensure that the parts are installed in the correct order Check correct functioning Coat the threads and gear wheels with STIHL multi purpose grease b 16 Reassemble remaining parts...

Page 28: ...sealing faces A gasket is not fitted between muffler and cylinder 217RA061 TG Reassemble parts in reverse order Defective oil seals and gaskets or cracks in housing are the usual causes of leaks Such...

Page 29: ...1 from the test flange 1128 850 4200 1 217RA064 TG Fit the test flange 1128 850 4200 1 Screw on the nuts arrows and tighten them down firmly 217RA066 TG 1 Oil seals tend to fail when subjected to a v...

Page 30: ...3 Carry out the same preparations as for the vacuum test b 8 2 2 Connect pressure hose 1 of tester 1106 850 2905 to nipple arrow 217RA067 TG 1 Close vent screw 1 on the rubber bulb VA 146RA063 1 Pump...

Page 31: ...eter of the oil seals b 16 Use the press sleeve 2 4112 893 2401 to install the oil sleeve 1 217RA294 TG 1 2 The seating face must be flat and free from burrs Turn the crankshaft through several times...

Page 32: ...ing parts in reverse order The complete engine must be removed before disassembling the piston or cylinder Remove the sprocket cover and bar and chain b 5 1 Remove the muffler b 8 1 217RA088 TG Remove...

Page 33: ...om underneath the engine housing 217RA106 TG Lift the handle housing slightly until the manifold flange lifts off the intake stub 217RA153 TG Pull the engine out of the engine housing 217RA110 TG Push...

Page 34: ...A021 TG The pin 1 must be lined up with the hole arrow when fitting the sprocket cover 1 217RA352 TG Tighten down the nut arrow and secure the sprocket cover 1 Now tighten down the screws securing the...

Page 35: ...b arrow 217RA157 TG 1 Push the insulating plate 1 into the guides arrows until it engages at the bottom Reassemble remaining parts in reverse order 217RA158 TG 1 Take out the screws arrows 217RA111 TG...

Page 36: ...ign the piston and crankshaft before inserting them in the cylinder The cylindrical crankshaft stub arrow must point towards the cylinder exhaust port 217RA143 TG For clarity the piston is not shown i...

Page 37: ...n on the closed crankcase Use oil seal 2 9639 003 1205 for installation on the open crankcase 2 217RA085 TG 1 Slip new oil seals onto the crankshaft stub with the open side facing the crankshaft 217RA...

Page 38: ...ll the engine b 8 4 2 Reassemble remaining parts in reverse order Remove the engine b 8 4 1 Remove the crankshaft b 8 5 1 Remove the ball bearing 1 and washer 1 217RA118 TG Remove the ball bearing 1 a...

Page 39: ...the washer 376RA123 TG 1 Fit the washer 1 376RA132 TG 1 Fit the ball bearing with the closed side arrow facing outwards Heat the inner race of the deep groove ball bearing to approx 150 C 300 F 376RA1...

Page 40: ...on must be held steady 217RA126 TG 1 2 during this process to ensure that jolts are not transmitted to the connecting rod Remove the piston 1 from the connecting rod Inspect the piston rings and repla...

Page 41: ...embly tool down in the sleeve until the magnet is at the end of the guide slits Stand the tool on a suitable surface wooden board 217RA139 TG Remove the sleeve and push it as far as possible over the...

Page 42: ...m piston Use a piece of old piston ring to scrape the grooves clean 217RA129 TG Install the new piston rings in the grooves so that the radii at the ends of the rings arrows face towards the piston he...

Page 43: ...25 TG Connector tag 2 for the short circuit wire Testing in the workshop is limited to a spark test A new ignition module with ignition lead must be installed if no ignition spark is obtained after ch...

Page 44: ...d can only be replaced together with the ignition module Examine the spark plug boot and replace it if necessary b 9 4 Reassemble parts in reverse order Moderately tighten the screws on the ignition m...

Page 45: ...nput terminal 1 Push the tester s output terminal 3 onto the spark plug High voltage risk of electrocution Crank the engine quickly with the rewind starter and check sparkover in the window 2 of the i...

Page 46: ...check the ignition system with the aid of the troubleshooting chart b 9 7 The ignition lead cannot be replaced separately as it is permanently connected to the ignition module Remove the ignition modu...

Page 47: ...ning arrow 217RA327 TG Slide the cover 1 over the spark plug boot Do not use either graphite grease or silicone insulating paste Install the ignition module b 9 1 217RA095 TG 1 Reassemble remaining pa...

Page 48: ...ghtening torques b 3 5 Check the short circuit wire if the spark plug and ignition lead with spark plug boot are in order Remove the fan cover b 8 4 1 Disconnect the short circuit line 1 1 217RA328 TG...

Page 49: ...01 TG Remove the cable guides arrows 217RA320 TG Remove the contact springs arrows from the handle housing 217RA318 TG Examine the wiring harness 1 contact spring 2 contact spring 3 and grommets arrow...

Page 50: ...ferent depths This means that the rear contact 217RA166 TG 1 2 3 spring 3 and the front contact spring 2 must make contact with the metal pin of the switch shaft when the switch shaft 1 is in position...

Page 51: ...correct Contacts shorted Clean adjust or replace the spark plug b 9 3 Check spark plug boot Firmly seated on spark plug leg spring Leg spring hook in centre of ignition lead Spark plug boot damaged Re...

Page 52: ...eck ignition lead Severe chafing Spark plug boot holes cracks Resistance of spark plug boot to ground required 1 5 12 kW Check resistance of ignition lead value required 10 W Replace spark plug boot a...

Page 53: ...fuel or carburetor system Check power unit for leaks Check position of flywheel on crankshaft b 8 2 b 9 5 yes Stop switch Check correct operation Short circuit wire chafed Contact springs not in conta...

Page 54: ...low it to rewind until its normal smooth action is restored Before installing lubricate the rewind spring and starter post with STIHL special lubricant b 16 If clogged with dirt or pitch the entire st...

Page 55: ...rope rotor 217RA258 TG Pull out the rope with the starter grip and carefully release the rope rotor The system will not be under tension if the starter rope or rewind spring is broken Remove the wash...

Page 56: ...he groove in the starter post 1 217RA251 TG Then slide the straight part of the spring over the starter post until it engages in the groove Tension the rewind spring b 10 6 Grease the pegs of the pawl...

Page 57: ...7 TG Machines with ElastoStart starter grip Prise off the cap 1 with a suitable tool 217RA353 TG 1 Pull the rope or remaining rope 1 out of the sleeve 217RA354 TG 1 Pull the rope 1 through the sleeve...

Page 58: ...ull out the rope 1 with the starter grip and straighten it out 217RA260 TG 2 1 Hold the starter grip firmly to keep the rope 1 tensioned Let go of the rope rotor and let the starter rope rewind slowly...

Page 59: ...y suitable tools screwdriver drift etc to the recesses and push the spring into its seat in the housing the spring slides out of the frame Remove the frame The rewind spring may pop out Ensure that th...

Page 60: ...move the starter rope and rope rotor b 10 4 Use a suitable tool to remove the damaged guide bushing from the fan housing Place the new guide bushing 1 in the hole in the fan housing 217RA278 TG 1 Inse...

Page 61: ...engine housing to secure the handle housing without transmitting vibrations Remove the carburetor box cover b 14 1 Remove the sprocket cover and bar and chain b 5 1 Remove the screw arrow 217RA182 TG...

Page 62: ...e upper guide arrow 217RA161 TG 1 Draw the front handle out of the engine housing with the spring facing downwards 217RA162 TG Examine the front handle 1 spring 2 and bearing plug 3 and replace if nec...

Page 63: ...if necessary Before installing the AV spring ensure that it has been fully turned into the bearing plugs arrows 217RA168 TG Reassemble parts in reverse order Tightening torques b 3 5 To prevent the en...

Page 64: ...emove the handle moulding 1 Throttle rod and actuating levers may drop out as the handle moulding is removed 217RA238 TG 1 Remove the throttle rod 1 1 217RA240 TG Remove the interlock lever 1 and thro...

Page 65: ...fit the screws and tighten them down securely 217RA239 TG Tightening torques b 3 5 Check correct functioning Remove the air filter b 14 1 Remove the air filter base b 14 1 1 Remove the handle moulding...

Page 66: ...e and the cam arrow must be present 217RA167 TG 1 Fit the switch shaft 1 pushing the rear contact spring 3 slightly to the side 217RA166 TG 1 2 3 Check operation The contact springs are fitted in the...

Page 67: ...ced as a complete unit see spare parts list Remove the cover 1 217RA103 TG 1 Remove the screw arrow 217RA108 TG Remove the bumper strip 1 217RA172 TG 1 Remove the screw arrow 217RA169 TG Take out the...

Page 68: ...se 2 out through the opening arrow 217RA299 TG 1 2 Push the grommet 1 out 217RA181 TG 1 Disconnect the impulse hose 1 from the stub arrow Remove the handle housing 217RA298 TG 1 Unscrew the spring and...

Page 69: ...tank Take care not to overextend the suction hose 1 217RA187 TG Hold the suction hose with blunt pliers Pull the pick up body 1 off the suction hose 217RA188 TG 1 Flush out the oil tank Replace the pi...

Page 70: ...8800 to pull the suction hose 1 out of the oil tank 217RA077 TG 1 Push the pick up body 1 into the suction hose and place it in the oil tank Reassemble remaining parts in reverse order 1 217RA340 TG I...

Page 71: ...g the valve A valve is installed in the tank wall to keep internal tank pressure equal to atmospheric pressure Remove the sprocket cover and bar and chain b 5 1 Remove the oil tank cap Drain the oil t...

Page 72: ...nto the hole in the engine housing with a drift dia 6 mm working from the outside 217RA196 TG Fit a new valve in the hole a approx 8 10 mm Reassemble remaining parts in reverse order 217RA339 TG Lift...

Page 73: ...s together and push the twist lock 1 out of the carburetor box cover 1 217RA330 TG Remove the air filter 1 Knock out the filter or blow it clear with compressed air from the inside outwards 1 217RA314...

Page 74: ...ly on the filter base all round Remove the air filter b 14 1 Remove the filter base b 14 1 1 Push out the grommet 1 examine it and replace it if necessary Reassemble parts in reverse order 217RA181 TG...

Page 75: ...tor onto the fuel port arrow 217RA178 TG Push the pressure hose of the tester 1106 850 2905 onto the double connector Close the vent screw 1 on the rubber bulb 2 and pump air into the carburetor until...

Page 76: ...In other words the diaphragm distorts and swells and must be replaced Examine the metering diaphragm for signs of damage and wear replace the gasket Note the order in which the metering diaphragm 2 a...

Page 77: ...edle must be replaced if a circular indentation arrow is visible on its tip VA 212RA281 Fit the inlet needle 1 Fit spring 2 in bore 217RA219 TG 2 1 Position the seat of the inlet control lever 1 with...

Page 78: ...tor body 217RA224 TG Carefully separate the pump diaphragm 1 and gasket 2 The diaphragm material is subjected to continuous alternating stresses and eventually shows signs of fatigue In other words th...

Page 79: ...cover back and forth until the pegs on the end cover are lined up with the 217RA199 TG holes in the carburetor body Insert and tighten down the screw Tightening torques b 3 5 Remove the carburetor b...

Page 80: ...pring and ball are correctly fitted before installing the choke shaft Slide the choke shaft 1 into the carburetor body until it engages 217RA215 TG 1 Turn the choke shaft until the flat area is visibl...

Page 81: ...ure the pump piston to prevent it popping out b 14 3 7 Unhook and relax the torsion spring arrow 217RA203 TG 1 Pull the throttle shaft 1 with torsion spring out of the carburetor body Clean the thrott...

Page 82: ...e carburetor body 217RA208 TG 1 2 The notch arrow on the throttle shutter must line up with the small bore in the carburetor body Tighten down the screw Check correct functioning and easy movement Sec...

Page 83: ...buretor b 4 6 Low speed screw Take out the low speed screw 1 1 217RA209 TG Examine the tip arrow for signs of damage or wear Replace the low speed screw if necessary Reassemble parts in reverse order...

Page 84: ...y b 8 1 Let the engine warm up Set idle speed with a speed tester Set the specified speeds within the tolerance range of 200 rpm 1 Set the speed to 3500 rpm with the idle speed adjusting screw LA 2 Tu...

Page 85: ...turn Engine stops when idling Make standard setting Turn the idle speed screw LA clockwise until the saw chain begins to run then back off 1 4 turn Saw chain rotates at idle speed Make standard setti...

Page 86: ...not yield any improvement refer also to the troubleshooting chart for ignition system carburetor and power unit b 4 6 Remove the air filter b 14 1 Remove the filter base b 14 1 1 Remove the carburetor...

Page 87: ...take port with the elbow flange Coat with STIHL Press Fluid b 16 In this way the elbow flange is fitted 217RA269 TG through the intake port of the tank housing without damaging it Ensure that the flan...

Page 88: ...e elbow out of the handle housing b 14 5 Troubleshooting b 4 6 or b 4 7 The impulse hose is shown on the handle housing after disassembly for clarity Disconnect the impulse hose 1 from the stub arrow...

Page 89: ...uel hose Remove the fan housing b 10 2 Drain the fuel tank Ensure that the fuel is disposed of correctly and without harming the environment Remove the cover 1 217RA103 TG 1 Disconnect the fuel return...

Page 90: ...ry Reassemble parts in reverse 2 217RA317 TG 1 order Impurities which are entrained into the fuel tank with the fuel are trapped by the pick up body With time the fine pores in the pick up body become...

Page 91: ...Slide the connectors of the cleaned or replaced pick up body 1 into the fuel hose 2 217RA291 TG 1 2 Push the pick up body 1 into the tank filler port The pick up body should be positioned at the lowe...

Page 92: ...e 2 and elbow connectors 3 and replace them if necessary 217RA307 TG 3 3 2 1 Reassemble parts in reverse order Remove the pick up body b 14 7 1 Prise off the flange 1 with a suitable tool 217RA293 TG...

Page 93: ...e opening in the handle housing 2 217RA317 TG 1 Disconnect the fuel hose 1 from the fuel pump 217RA304 TG 1 Disconnect fuel hose 1 and examine fuel hose 2 replace if necessary Reassemble parts in reve...

Page 94: ...and sealing ring the sealing ring is available separately 1 217RA297 TG 2 Press the nipple into the mount arrow inside the tank Screw in the filler cap Test for leaks Reassemble remaining parts in 217...

Page 95: ...s 11 Puller 5910 890 4501 Remove limiter cap 12 Puller with No 3 1 jaws 5910 890 4400 Remove oil seals 15 Press sleeve 4112 893 2401 Press in oil seal 16 Assembly tube 1117 890 0900 Hook in clutch spr...

Page 96: ...lectric or pneumatic screwdrivers tighten down screws with torque wrench 35 Bit T 20 x 125 0812 542 2041 Remove and install spline socket head screws with electric or pneumatic screwdrivers tighten do...

Page 97: ...3 0781 957 9000 Rubber buffers in AV system 4 STIHL multi purpose grease 0781 120 1109 High voltage output on ignition module 5 Dirko HT red sealant 0783 830 2000 Engine pan oil seals outside 6 High s...

Page 98: ...englisch english 0455 217 0123 M5 B5 T Printed in Germany...

Reviews: