1. Stihl MS 440/044 Chainsaw SECTION: Tools and Equipment
ISSUED: REVISED: ##-####

2. Objectives To provide an understanding of the following Specifications
Use
Maintenance
Safety

3. Specifications STIHL MS 440/044 20” Bar Chain 33 cutting teeth
Carbide tipped
HD air filter with pre-filter
2 stroke engine
5.2 horse power
50:1 pre mix
Spark plug
Bosch WSR6 F or NGK BPMR 7A
Idle RPM-2,500
Max RPM-13,500

4. Use Vertical ventilation Forcible entry Cutting timber and brush
Cutting lumber
Shoring operations

5. Control Lever Positions
Stop
Run
Half choke
Choke
Interlock and throttle must be depressed
to switch from run to half choke or choke

6. Parts Chain brake Decompression valve Manual and inertia operated
Allows for an easier and quicker start

7. Parts Chain catch Chain tensioner
Reduces risk of operator contact with chain should it break or derail
Chain tensioner
Allows for chain tension adjustment

8. Starting Procedures Ground starting method Place saw on ground
Disengage chain break
Ensure control lever is in choke position
Hold handle firmly with left hand

9. Starting Procedures Place foot firmly in handle Pull starter grip
Repeat until engine fires
Adjust control lever to half choke
Pull starter grip until saw starts and runs

10. Starting Procedures Quickly depress interlock and throttle
Places saw in run position
Do not pull start rope to its full extension

11. Starting Procedures Drop starting method Ensure brake is disengaged
Ensure control lever is in choke
Hold handle with left hand
Hold starter grip with right hand

12. Starting Procedures Raise saw slightly above waist
Let saw drop in a controlled manner
Pulling starter grip
Repeat until saw fires
Adjust master control valve to half choke

13. Starting Procedures
Continue to drop and pull starter grip until saw fires and runs
Quickly squeeze throttle and interlock
Puts saw in run position
Do not pull start rope to its full extension

14. Procedures Disengage brake Rest tip of the saw’s bar on ground or roof
With left hand, keep thumb on handle
Pull back on the chain brake to disengage

15. Procedures Stopping the Chain
Release throttle to bring saw to idle
Engage chain brake with back of left hand while holding handle
Turn saw off by raising control lever to the stop (top) position
Always place saw in ready to run position when placing back into service
Brake disengaged, throttle trigger interlock depressed and the control lever in the choke position

16. Maintenance Basic Refuel after use
Refill chain bar oil whenever you refuel
Adjust chain tension ensuring the chain can slide across the bar
Approximately 1/16” gap between bar and chain
Rotate guide bar when chain is removed to extend bar life
Inspect chain for damage
Replace when 3 consecutive teeth or 6 total teeth are missing or when a tie strap is broken
Saw may need a complete tear down to ensure it is thoroughly cleaned of all dirt and debris
Pay extra attention to the cooling fins. Over time they can accumulate “gunk” and cause the saw to overheat.

17. Maintenance Advanced Recommended tools Scrench
Stihl combination wrench
Stihl flathead screwdriver
Larger flathead screwdriver
Stihl provided torques style wrench
Cleaning solvent or WD-40

18. Air Filter System Set master control lever to full choke
Open the twist lock above and remove the carburetor box cover

19. Air Filter System Remove filters and check outer butterfly position
Ensure its closed
Separate filter components
Clean filters by using compressed air
Blowing from the inside out
In case of stubborn dirt, wash filters with warm soapy water
Rinse from the inside out
Let air dry
Outer Butterfly
Felt Prefilter
HD Filter
Standard Filter

20. Clutch and Chain Assembly
Unscrew the nuts and remove chain sprocket cover
Note side of stamped serial numbers or graphics on chain bar
Bar must be flipped when re-installed
Stamped Serial #

21. Chain and Bar Removal
Loosen chain by turning tensioning screw counterclockwise
Once chain starts to sag on the bottom of the bar, remove the bar and chain
Chain Tensioning Screw

22. Chain and Bar Cleaning
Use parts cleaner to thoroughly clean chain and bar
Inspect chain and determine if it needs to be out of service.
3 missing teeth in a row
6 missing teeth total
1 broken link
Use a small screwdriver to remove debris from the bar chain guide
Use compressed air to blow excess solvent from the chain and bar and dry with a rag

23. Powerhead Cleaning
Remove the inner side mounting plate by removing the screw adjacent to the tensioning screw
Remove the chain catcher with the Stihl torx wrench

24. Powerhead Cleaning
Removing the E clip from the crank shaft using small screwdriver
Remove clutch drum assembly
Place the needle cage in a cap full of bar oil to lube
Clutch Drum
Rim Sprocket
Needle Cage
Washer
E-Clip

25. Powerhead Cleaning
Use compressed air to blow as much debris off of the powerhead
Remove the two cover plates using the Stihl torx wrench
Use the parts cleaner to further clean the powerhead
Use caution with the solvent avoiding the carburetor intake
Clean thoroughly
Use compressed air to blow off any excess solvent and dry with a rag

26. Powerhead Cleaning Clean all parts using the parts cleaner
Use compressed air to blow off excess solvent and dry with a rag
Set aside once cleaned and try to keep everything organized

27. Chainsaw Reassembly Now reassemble the powerhead in reverse order
Starting with the following
2 cover plates
Clutch drum assembly
When installing the clutch drum, rotate and apply slight pressure until the oil pump drive spring engages the slot on the outside diameter of the drum
There should be a noticeable connection when the drum catches and drops into place
The slot on the drum is identified with a mark located on the face of the drum

28. Chainsaw Reassembly Continue reassembling in the following order
Chain catcher
Inner side plate
Bar and chain
Sprocket cover
Air filter
Carburetor box cover

29. Chainsaw Reassembly Replace bar and chain
Ensure the bar is flipped to the opposite side from where it was initially assembled
This will help with wear over time
Ensure the chain is properly seated in the bar and sprocket

30. Chainsaw Reassembly
Apply tension to the chain by turning the chain tension screw clockwise
Take some of the sag out of the chain
Install the sprocket cover and finger tighten the two nuts

31. Chainsaw Reassembly Adjust the tension of the chain
Appropriate tension has been applied when:
With a gloved hand, pull the chain upward from the middle of the bar to create a gap equal to the width of a nickels edge being exposed between the chain and bar
With the chain brake off, the chain can be spun around the bar
Use the Scrench to finish tightening the sprocket cover nuts until snug
Do not over tighten

32. Chainsaw Reassembly Refuel with 2 stroke pre-mix 50:1 fuel
Top off bar oil
Test Run
Ensure adequate chain lubrication by running at full throttle and aiming saw towards the ground
A light spray pattern of oil should begin to form on the ground
Adjust if necessary
Re-adjust chain tension if necessary
Place back into service in the “Ready Run Position”

33. Chainsaw Maintenance
Refer to Stihl Owner’s Manual for further maintenance needs

34. Safety Always wear proper PPE when operating chainsaws.
Minimum- helmet, eye protection, gloves, and hearing protection while performing maintenance
Avoid cutting overhead and inline with body
Maintain a firm grip at all times
Cut at full throttle

35. Safety Common reactive forces when cutting
Kickback
Occurs when saw chain near upper quadrant of bar nose contacts a solid object causing the saw to fling up and back in an uncontrolled arc
Pushback
Occurs when the chain on the top of the bar is suddenly stopped or caught, driving the saw straight back into the operator
Pull in
Occurs when the chain on the bottom of the bar is suddenly stopped or caught, causing the saw to be pulled forward
Let the saw cool before refueling