What chainsaws does CCFD carry?
Stihl MS461 and Stihl MS462
What type of engine do our saws have?
Two-stroke engine
What is the fuel mixture for our saws?
50:1 premix fuel
What type of oil do we use for the fuel mixture?
Two stroke oil
What type and size of guide bar do we use?
20” sprocketed guide bar
1.6 mm guide
Is the oiling system for the chain manual or automatic?
Automatic (Student must identify where the port is)
How often do we fill the bar oil? Why?
- After every use and when needed
- The saw is designed to run out of fuel before it runs out of bar oil
What can be substituted for bar oil in an emergency?
- 30 wt motor oil, however the saw must be taken out of service after
What are the methods of operating the chain brake?
- Manual
- Inertia
- Kick back
Master control positions:
- Stop: Inhibits Spark
- Run / On: Spark
- Warm Start: Half Choke
- Cold Start: Full Choke
What chains do we use for our saws?
461 & 462: we use the 3/8” RDR Special Carbide with 1.6 mm guide teeth
Out of Service Criteria - Damaged teeth in a row
3 or more
Out of Service Criteria - How many total damaged teeth?
5 or more
Out of Service Criteria - What other factors will result in removing the chain from service?
Cracked or broken tie straps
Chain Tensioning - Step 2
Grasp bottom of chain and pull down. There should be no more than 4 complete drive links exposed and no less than 3 drive links visible. If the chain is too loose, it will throw from the bar during operation. If it is too tight, it will damage the bar.
Chain Tensioning - Step 1
Disengage the chain brake; must have two points of contact which are:
* Tip of bar to solid object
* Left hand on throttle handle
Chain Tensioning - Step 3
In order to adjust the chain, the bar mounting screws must be loosened first and then the adjustment is made. Once adjustment is made, the screws are tightened.
Chain Tensioning - Step 4
Grasp the chain with a gloved hand and attempt to roll the chain along the bar. Ensure chain is seated in the sprocket.
Chain Tensioning Final Note
A new chain shall be run for a minimum of 5 minutes at half-throttle prior to in-service use. Let the chain cool and repeat the chain tensioning process.
Starting Procedures
- Ensure manual chain brake (hand guard) is disengaged.
- Depress throttle trigger and lock.
- Place master control lever in the COLD START position. (Do not squeeze throttle trigger). Note: If saw has been running use WARM START position.
- Prior to pulling cord, pull slack out of cord until resistance is felt. Use modified drop start method (between legs) to pull starter cord until engine starts to fire or coughs.
- Move master control lever to WARM START position. Continue pulling cord until engine starts.
- When engine starts, immediately release the throttle lock.
- Apply the chain brake.
Disengaging the Chain Brake
- Set the tip of the saw on the ground. With finger off the trigger, release the chain brake with free hand. (Must maintain two points of contact.)
- Apply the chain brake using the back of hand by rotating the tip of the bar upwards until the brake comes in contact with the back of hand, causing the brake to engage.
Shut-Off Procedures
- Bring saw to idle.
- Engage the chain brake. (Saw must be at idle first.)
- Move the master control lever to STOP position.
Flooding Procedures
- Turn saw to OFF position.
- Utilize the decompression button, if present.
- Pull starter chord 20-25 time to purge fuel out of the piston cylinder.
- Turn saw to ON position.
- Pull starter chord until saw starts and maintains idle. Feather the throttle to assist the saw if necessary.
- Once saw is maintaining idle, run throttle wide open to burn off excess fuel in piston cylinder.
- Allow saw to slow back to idle and apply brake.
Returning Saw to Apparatus
Refill saw with fuel and bar oil. Clean excess oils, fuel or dirt.
