How to Tighten a Chainsaw Chain

Here is how to tighten worn or loose chains that have lost bar tension over many uses of your chainsaw.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• 1 wrench sized to fit bar retaining nut
• 1 screwdriver
• 1 Can of WD-40 12 oz.
• Rags
• 1 pair of work gloves

1. 
    

   Locate and loosen chain bar retaining nut.

2. 
    
   Chain Adjusting screw

   Locate chain adjusting screw between the loosened bar and the motor housing.

3. 
    

   Generously spray WD-40 oil behind the bar and around the chain adjusting the nut, and wipe this area as clean as possible with a clean rag.

4. 
    

   Turn chain adjusting screw clockwise one rotation to tighten chain.

5. 
    

   Check tightened chain tension by gripping chain at the mid point of the bar and pulling upward. To be properly tight ,the chain should be snug against the bar but loose enough to rotate freely around the bar as the chain is pulled forward by hand.

6. Repeat Step 4 if chain is too loose (1/8 inch gap or greater between bar and chain when lifted by hand).

7. 
    

   Loosen chain if too tight (if it will not rotate on the bar with hand pressure) by turning the chain adjusting screw 1/2 turn counterclockwise.

8. 
    

   Recheck chain tension as in Step 5 and adjust if necessary. If the chain is properly tensioned, use your wrench to tighten the bar retaining nut.

Tips & Warnings

• Depending on how hard and how frequently the chain saw has been used, thoroughly cleaning behind the chain bar and around the chain adjusting screw will make all of these adjustments easier.
• Do not over tighten chain. Leave a 1/16- to 2/16-inch gap between chain and bar, as the chain will tighten during use.
• Always wear heavy work gloves when manually attempting to rotate or otherwise move the chain.