Setup and Service Procedures for the MS 170, MS 180 Chain Saw
© STIHL Inc., Virginia Beach, VA
2013
Introduction confidential
The
MS 170, MS 180 chain saw has a 2-cycle engine STIHL assigns a 4 digit series number to every product The MS 170, MS 180 is assigned the 1130 series number The
1130 series of saw was introduced to the market in 1995 as an 017, and then in 1998 the 018 was added In 2002 the model designation changed from 017 to MS 170, and 018 to MS 180
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Specifications MS 170 Engine Displacement 30.1 cc (1.8 cu.in) Engine Power 1.3 kW (1.7bhp) Weight 3.9 kg (8.6 lbs) Fuel Capacity 250 cc (8.5 oz.) Chain Oil Capacity 145 cc (4.9 oz.) Recommended OILOMATIC® Chain Guide Bar Lengths Available Engine
Idle Speed Wide Open Throttle
© STIHL Inc., Virginia Beach, VA
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MS 180 31.8 cc(1.9 cu. in.) 1.5kW (2.0 bhp) 4.0 kg (8.8 lbs.)
3/8” PMM3 12” to 16”
2800 RPM 14,000 RPM (with bar and chain installed)
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Become Familiar With the Controls confidential
Master
Control Lever™ A single lever operating the choke, throttle lock and on-off switch 0 = Off I = Ignition on Warm Start Cold Start
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Starting Features confidential
The
MS 170 is equipped with a standard starter mechanism, and with 2 bar nuts holding the bar in place The MS 180 C-B has the Toolless Quick Chain Adjuster (QCA) for fast and easy chain and bar install and adjustment The MS 180 C-BE also has the Easy2Start™ starter mechanism which allows starting with less effort at a lower cranking speed © STIHL Inc., Virginia Beach, VA
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Starting Features confidential
The
MS 180 C-B has the standard starter mechanism, which requires a brisk pull on the rope to it’s full extension to start the engine The MS 180 C-BE has the Easy2Start™ starter mechanism, which allows starting by simply pulling out the rope slow and easy, winding the auxiliary spring which then spins the motor over to start it Notice that the MS 180 C-BE has a deeper recoil housing and the handle extends out slightly farther for clearance © STIHL Inc., Virginia Beach, VA
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confidential
Kickback!!! Kickback occurs when the moving saw chain near the upper quadrant of the bar nose contacts a solid object or is pinched The greater the force of the kickback reaction, the more difficult it becomes for the operator to control the saw
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Chain and Bar Color Code Marking confidential
STIHL
saw chain will have a green or yellow tie strap to indicate if the chain is low-kickback or other than low-kickback The bar will have two green or yellow dots on the powerhead end of the bar to identify if the bar is a reduced kickback bar or not
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Install the Bar and Chain confidential
STIHL
recommends the use of reduced kickback bars and low kickback chains on all STIHL chain saws Yellow bar and chain combinations are for trained professionals with extraordinary cutting needs Be sure the bar and chain are within the recommended length for the model of saw being assembled Always wear gloves when handling saw chain to protect your hands from the sharp cutters © STIHL Inc., Virginia Beach, VA
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Install Bar & Chain: Quick Chain Adjuster confidential
Install
the tensioning gear and fasten the screw securely The bar can be installed with the STIHL logo facing up or down; periodically the bar should be flipped to spread the wear over both edges of the bar
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Install Bar & Chain confidential
Make
sure the cutters on top of the bar are facing away from the powerhead! WRONG WRONG
CORRECT
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Quick Chain Adjuster (QCA) confidential
The
QCA allows the user to adjust the chain tension without tools
Loosen the wing nut Rotate the adjusting wheel Tighten the wing nut
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Install Bar & Chain confidential
If
the saw does not have a QCA simply remove the 2 bar nuts, install the bar and chain, making sure the adjusting pin is in the hole in the bar
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Install Bar & Chain confidential
Install
the cover and the 2 nuts leaving them just snug against the cover
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Chain Adjustment confidential
The
1130 saws have a front chain tensioner Most STIHL chain saws have a side chain tensioner that is more convenient to use Saws come with a combination wrench, commonly referred to as a “Scrench”, to make bar and chain service easy to do
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Install Bar & Chain confidential
Adjust
the chain tension with the “Scrench” by holding up on the nose of the bar, tightening the chain tension screw, then tightening the nuts
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Correct Chain Tension confidential
With
the chain brake disengaged, pull the chain through from the top side and it should rotate freely without any slack appearing If the chain goes from tight to loose the sprocket and chain may not be of the same pitch, or the sprocket and chain may have excessive wear and no longer have the same pitch © STIHL Inc., Virginia Beach, VA
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Correct Chain Tension confidential
Regardless
of bar length, check for correct chain tension by pulling up on the chain at the center of the bar
The
tension is correct when the bottom of the drive link will just clear the bar groove
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Cutterless Chain for Service confidential
For
any chain saw, to properly tune the carb or verify running RPM at idle and wide open throttle a bar and chain should be installed Cutterless chains are available to provide a safe way for the service technician to do this without fear of the chain coming into contact with anything
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Chain Brake confidential
All Current Models of STIHL Chain Saws are Equipped with the STIHL Quickstop® Chain Braking System The chain is stopped and locked when the hand guard is pushed toward the guide bar nose by the left hand – or when the brake is activated by enough inertia in certain kickback situations Brake Brake Band Band Engaged Disengaged
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Starting the 1130 Saw confidential
Fill
the tank with 89 octane brand name fuel with STIHL two-stroke oil mixed at a 50:1 ratio, or use STIHL MotoMix
Add
bar oil to the oil tank for chain lubrication
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Starting the 1130 Saw confidential
Push
down on the interlock on the top of the handle and then squeeze the throttle all the way open and hold it
Place
the Master Control Lever™ in the full choke position, down to the #1 position
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Instruction Manual Directions for Safely Starting a Chain Saw (Never Drop Start a Chain Saw!)
© STIHL Inc., Virginia Beach, VA
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First Time Start-Up confidential
When
the engine starts, commonly referred to as a “false start”, move the Master Control Lever™ up to #2, to open the choke and then pull the rope again The engine should start and run at fast idle Quickly “blip” the throttle to release the engine from the fast idle position
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First Time Start-Up confidential
If
a saw is left in the fast idle position with the chain brake engaged for even a very short period of time it may overheat the clutch and chain brake components and possibly ruin the tank housing as well
To
stop the engine raise the Master Control Lever™ to the 0 (off) position, #4 in the picture
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First Time Start-Up: Warm Up confidential
After
the engine has started and the chain brake has been released, slowly squeeze the throttle about half way open and then slowly release it back to idle Do this several times, for at least 20 seconds, to completely purge any remaining air from the carburetor circuits and to allow the chain lubrication pump time to prime the system with bar and chain oil Never
allow any chain saw engine to run at full throttle without a load, regardless if it is new or broken-in, for more than a few seconds
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Bar & Chain Oiler Check confidential
Carefully
hold the tip of the bar over a piece of wood or cardboard
Run
the saw at half throttle and verify that a line of bar and chain lubricant is being slung off the end of the bar
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Factory Testing of All STIHL Products confidential
Every
engine manufactured by STIHL has been started and operated in a test cell The test cell makes carburetor adjustments and verifies that the engine runs properly at idle, acceleration, and at full throttle under load The test cell measures the running performance and emissions and verifies that they are within acceptable parameters All the dealer needs to do is service the unit and verify it is ready for the customer to operate it It is extremely rare that a new unit will need any major adjustments or repair © STIHL Inc., Virginia Beach, VA
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Fault Analysis: STIHL Engine Check confidential
When
a unit is running poorly or not at all, using a systematic approach to identify any and all faults present will allow the Service Technician to quickly and efficiently determine what is wrong
It
is just as important to know what faults are not present as well as faults that do need to be addressed
© STIHL Inc., Virginia Beach, VA
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DG Screws confidential
STIHL
uses the DG type of fastener in manufacturing because they cut their own threads the first time they are used Notice that the ones holding into plastic have a different pitch and profile than the ones that hold into For Metal For Plastic metal It is imperative that the Service Technician keep track of which screw is which and not screw them into the wrong base material or the threads will be damaged It is also best practice that when starting a DG screw into the hole, slowly rotate it backwards until it “clicks” to index the threads, then turn it clockwise to tighten it © STIHL Inc., Virginia Beach, VA
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1. Deflectors, Shrouds, Covers, Fasteners confidential
Visually
look the unit over for damage, missing items, loose fasteners, or anything else that is obvious
Damaged shroud may be a safety hazard for the operator
Operated without an air filter or cover © STIHL Inc., Virginia Beach, VA
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2. Warning Labels confidential
Verify that warning labels are present and readable On a chain saw the only label the service technician should be concerned with is the one on the chain brake handle If this label is damaged or worn away, a universal replacement label is available from STIHL White Chain Saw Label: 0000 967 3613
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3. Cutting Attachment confidential
Note
type and condition Inspect for wear or damage Bar, chain, and sprocket within wear limits
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3. Cutting Attachment
4. Belt Tension confidential
If
the unit is a trimmer or a concrete saw: Tap head eyelets worn, spool worn, retainer secure Belt tension correct; belt worn or frayed
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5. Operator Controls confidential
The
interlock should be sticking up out of the handle, and it must be depressed flush with the handle before the throttle trigger will move
Be
sure the throttle moves freely
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5. Operator Controls confidential
The
throttle must be squeezed all the way open before the Master Control Lever™ can be actuated to the full choke position, then release the throttle and the Master Control Lever™ should stay in the choke position
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5. Operator Controls confidential
Now
raise the Master Control Lever™ up one notch with your thumb, and it should stay in the warm start, half choke position
Now
squeeze the trigger and it should snap up to the I position automatically
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5. Operator Controls confidential
Finally
the Master Control Lever™ should easily slide up to the O position
Any
problem with the Master Control Lever™ should be noted for repair
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5. Operator Controls confidential
When
the chain brake handle is actuated back and forth, there should be an audible “click” In the forward position the sprocket must not turn In the back position the sprocket must spin easily © STIHL Inc., Virginia Beach, VA
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6. Verify Anti-vibration Components confidential
Most
STIHL chain saws and line trimmers have an anti-vibration system that should be inspected for wear and damage Some models do not have any antivibration components so this step would not apply
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6. Verify Anti-vibration Components confidential
Hold
the bumper spike against the edge of the workbench and put pressure against the handle assemble There should be strong resistance to movement but there should be some “give” to the antivibe rubber bushings There should not be any looseness to the handle assembly © STIHL Inc., Virginia Beach, VA
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7. Inspect Starter System confidential
Inspect rope, handle, and eyelet for wear or damage Pull the rope to it’s full extended length and be sure it is not about to break at the very end
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8. Inspect Air Filter
9. Inspect Air Filter Housing confidential
Remove
cover and the top of the filter is the clean side There should not be dirt or debris on this side of the filter or down in the throat of the air intake Remove the filter and the bottom side is the dirty side There should be a pinch mark all the way around the edge of the filter to seal it Verify that the housing is not cracked or damaged © STIHL Inc., Virginia Beach, VA
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10. Carburetor Mixture Screws confidential
Most
STIHL products have mixture adjustment screws on the carburetor and will be equipped with a limiter cap on the H mixture screw and may have one on the L screw also The limiter cap allows the operator to adjust the carb leaner only to compensate for operation in high altitude If a cap is missing it should be considered as a fault and it is possible the screw may be set too lean © STIHL Inc., Virginia Beach, VA
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L mixture screw with cone to guide the screwdriver in place
H mixture screw with limiter cap in the up, or released position to allow the technician to make adjustments 22
10. Carburetor Mixture Screws confidential
The
1130 saws do not have mixture screws or limiter caps Notice that the H and L holes are not threaded and are blocked off internally The only adjustment on a 1130 saw is to set the idle speed with this screw It also makes slight mixture adjustments as the idle speed is tuned This carburetor uses a fixed orifice jet to regulate the amount of fuel available to the engine and is not adjustable © STIHL Inc., Virginia Beach, VA
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10. Carburetor Screw Settings confidential
4229 121 2701
Limiter
caps can be removed by the service technician for carb service Removal of this style of limiter cap is done with the 5910 890 4501 tool Anytime a cap is removed best practice is to replace it with a new one On the 1130 saws this step does not apply
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Hose Removal confidential
The
5910 890 4501 tool also works well to remove fuel, impulse, or vent hoses
Use
a side to side rocking motion while pushing against the hose to walk it off of the fitting
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11. Spark Plug Connection confidential
Use
a twisting motion to remove the spark plug connection and be careful not to pull the clip out of the high tension lead Inspect it for damage, hardness or cracks
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12. Spark Test confidential
Connect
a spark tester and pull the rope through as if trying to start the engine If no spark is present try again with a new plug A fouled or defective spark plug may not show spark on the tester even if the ignition system is OK © STIHL Inc., Virginia Beach, VA
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12. Spark Test confidential
If
there is still a no spark condition with a new plug, carefully disconnect the ground wire from the terminal on the ignition module and now see if spark is present If there is no spark the module is faulty If there is spark the stop circuit is faulty
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12. Ignition Shut-Off Function confidential
If
spark is present then place the Master Control Lever™ in the off position and pull the rope through and verify that no spark is present This verifies that the stop switch and connecting wiring is in order
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13. Spark Plug confidential
Verify
that the correct plug is installed for an 1130 saw:
Bosch WSR6F STIHL Part Number 1110 400 7005 NGK BPMR7A STIHL Part Number 0000 400 7000 Other
units may use a different part number with a different heat range, so always look it up! Set all STIHL spark plugs at .020”
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13. Spark Plug Appearance confidential
Normal color, normal electrode wear due to high run time Normal color and wear Carbon buildup due to high run time Both of these plugs have served their useful life © STIHL Inc., Virginia Beach, VA
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Heavy carbon buildup and oil fouled Mix ratio incorrect. Black, sooty appearance Caused by rich fuel/air mixture
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14. Muffler confidential
Remove
the 2 muffler nuts and deflector plate and inspect the spark arrester screen It must be present for all hand held engines used in the United States The screen may be blocked with carbon deposits If necessary shine a light through the screen to verify
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Remove Starter Housing confidential
Remove
fuel and oil tank caps Rock the cap retainer to the side Remove starter housing
Reinstall
the caps if necessary to prevent fuel or oil from running out on the work area
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15. Cylinder Leak Down Test confidential
This test typically is not necessary on a two-stroke engine but can be done to verify how well the rings are sealing with the flywheel blocked so the piston is slightly down from TDC A leak down test should always be done on a four-stroke engine because the piston and rings cannot be observed visually The leak down test also verifies that the intake and exhaust valves are sealing properly
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16. Inspect Exhaust Port and Piston confidential
With
the muffler removed use a flashlight and look through the exhaust port to be sure the port is not clogged up with carbon deposits Move the piston up and down and inspect the surface of the piston skirt for scoring or damage A piston in good condition will still have the radial machine marks across the skirt indicating little or no wear © STIHL Inc., Virginia Beach, VA
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16. Inspect Exhaust Port and Piston confidential
Spray
some lubricant on the rings and when the flywheel is turned back and forth slightly it will be apparent if the rings are free in the lands Lower the piston to BDC Inspect the intake side of the cylinder wall for wear or damage
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17. Cooling System confidential
Verify
that the cooling fins are in good condition and that the air path to the flywheel and through the engine from the flywheel is not blocked or restricted in any way Verify that the flywheel fins are in good condition
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18. Magneto Air Gap confidential
Line
up the pole shoes in the flywheel with the magneto Observe the gap between the ignition module and the flywheel The specification is .008” It is not absolutely necessary to measure this with a gauge, just be sure the flywheel is not rubbing on the module and that the gap does not look excessively wide © STIHL Inc., Virginia Beach, VA
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19. Fuel Tank confidential
If
the tank is empty look down in the tank to see if it appears contaminated with debris or anything else that shouldn’t be there If the unit has fuel in it carefully remove the cap and wave your hand over the opening while smelling for a sour odor that may indicate old stale fuel
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19. Fuel Tank confidential
If
fuel is present carefully pour the fuel out in a pan and see if there is trash or debris, or any evidence of other contaminants such as water in the fuel
This
sample is contaminated with water and debris Dispose of fuel properly
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20. Fuel Filter confidential
Use
the 5910 893 880 hook tool to fish the fuel filter out of the tank for inspection The filter body screen should be clear and in good condition, and the element may have oil staining but should not be dark or fouled or have any kind of coating on it
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Pressure Vacuum Tester confidential
0000
850 1300 Pump With the knurled ring to the right the gauge indicates pressure With the knurled ring to the left the gauge indicates vacuum
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20. Fuel Filter confidential
It
is a good idea to backflow a fuel filter with the pressure pump to verify that it is not restricted Hook up the tester and place the filter on a towel and pump the tester 2 times No pressure should build up and if the filter is wet with fuel it should clearly flow out
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21. Pressure Test Fuel Line confidential
Connect
the pressure tester to the fuel line where the filter was removed and gently pump it up no higher than 10 PSI If it holds steady then the fuel line is OK, and the carb itself passes the pressure test If
the gauge does not hold then either the fuel line or the carb may be leaking, so isolate the fuel line and test it by itself to determine where the fault is
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Remove Carb confidential
Hold
the choke shutter closed and carefully remove the link
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Remove Carb confidential
Carefully
slide the fuel line off of the fitting
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Remove Carb confidential
Hold
the throttle wide open and carefully remove the link
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Remove Carb confidential
Gently
pry the Master Control Lever™ up on the left side
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Remove Carb confidential
Slide
the Master Control Lever™ to the left and let it hang out of the way by the ground wire
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Remove Carb confidential
Hold
the fuel line down out of the way and slide the carb off of the studs
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21. Pressure Test Fuel Line confidential
To
test the fuel line by itself, plug one end and test through the other It should hold steady at 10 PSI
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22. Pressure Test Tank confidential
Be
sure there is no fuel in the tank before applying any pressure to the fuel tank! The pressure test verifies that the tank does not have a leak in any location, such as a grommet, seam, cap or hose Apply about 8 PSI max and it must hold steady If it leaks down at all use soapy water in a spray bottle to locate where the leak is © STIHL Inc., Virginia Beach, VA
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23. Vacuum Test Tank Vent confidential
Reverse
the tester into vacuum mode and pump hard and fast to see the needle indicates that some negative pressure is present in the tank Stop pumping and watch the gauge and the needle should move back up towards zero rapidly If the needle does not leak back to zero quickly the tank vent must be replaced and then re-test © STIHL Inc., Virginia Beach, VA
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24. Inspect Intake Side Of Piston With
the carb removed look through the inlet port and rotate the crankshaft to inspect the intake side of the piston The machine marks should be present on a piston in good condition Scoring or a dull gray appearance would indicate lack of lubrication, dirt ingestion, or possibly other problems that would prevent the engine from running properly © STIHL Inc., Virginia Beach, VA
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25. Impulse Signal Present confidential
Most
two-stroke engines have a passageway between the crankcase and the fuel pump side of the carburetor to cause the fuel pump diaphragm to flex back and forth with the pressure/vacuum that is created by the piston moving up and down It is rare that there is no impulse signal, but always verify that it is present because no impulse signal will cause a hard to diagnose, unusual running behavior that will appear to be carburetor related © STIHL Inc., Virginia Beach, VA
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For this blower engine the impulse signal comes out through the flange here:
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25. Impulse Signal Present confidential
For
the 1130 saw, remove the white plastic sealing ring, use the tapered adapter and connect the tester to the impulse port By hand, rotate the flywheel back and forth and the needle on the gauge should bounce back and forth indicating the impulse signal is present
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26. Vacuum and Pressure Test of Crankcase confidential
A
two-stroke engine needs an air tight crankcase since the air fuel mix is coming through the crankcase on the way to the combustion chamber Test to verify that there are no leaks at places like gaskets or RTV silicone sealed mating surfaces, and that crankshaft seals are not leaking under pressure or vacuum Block off the exhaust port by slipping a rubber block off plate in between the cylinder and the adapter plate, then install spacers and snug up the nuts while pulling the rubber up to get a complete seal © STIHL Inc., Virginia Beach, VA
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26. Vacuum and Pressure Test of Crankcase confidential
The
Service Manual for each model describes how to do this test and gives the part number for the adapters
For
the 1130 saw the special adapter for the carb side is part number 1118 850 4200
Be
sure the spark plug is installed and tight
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26. Vacuum and Pressure Test of Crankcase confidential
Use
the tester to pull a 0.5 bar vacuum; it should hold steady or not leak back to 0.3 bar within 20 seconds Rotate the crankshaft back and forth while the crankcase is under vacuum to verify that the seals are holding properly Pump 0.5 bar of pressure into the engine and it should hold steady for at least 20 seconds
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Pressure Test Results confidential
If
the unit fails the pressure test check obvious things first, such as the rubber sealing plate on the exhaust and the spark plug, by spraying with soapy water and looking for bubbles If they are sealing properly then the engine may need to be taken apart far enough to be able to check the crankshaft seals and the seal between the cylinder and the crankcase If an engine leaks under vacuum but holds under pressure it is most likely a crankshaft seal
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27. Crankshaft and Bearing Condition confidential
See
if the flywheel moves in and out or up and down There should not be any loose play in the crankshaft bearings
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28. Carburetor confidential
Pressure
test the carb no higher than 10 PSI and it should hold
steady Open and close the butterfly and it should open smoothly Verify that the throttle shaft does not have any excessive side to side play Inspect the carb for any physical damage
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29. Other Observations; Final Running confidential
This
is where any other observations about the unit not specifically covered by one of the numbered items on the STIHL Engine Check can be recorded
Once
repairs have been made the last part of the STIHL Engine Check document can be used as a quality control check to be sure the engine starts easily and is running to specification
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Final Check: Roll Out Test confidential
With the engine warmed up and idling, and the chain brake engaged on a saw, slowly roll the engine over so one side faces the ground Now roll it back upright, then roll the other side towards the ground Idle RPM should not change more than 200300 RPM If the idle changes the engine may have an air leak or other fault
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confidential
This presentation has been prepared by: Eddie Anderson Technical Training Supervisor STIHL Inc. Virginia Beach, VA
[email protected]
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