How To Repair Pole-Saw When Chain Comes Off Guide Bar

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If your chain is tensioned too loose, it may release from the guide bar during operation, which would be dangerous. Proper chain tension should be maintained at all times. Keep in mind that as the chain warms during use, the chain will naturally loosen. Properly tension your chain before beginning to use the machine, and then check every 20 minutes for the first hour of use. It is likely that after 20 minutes of use, the chain will need to be tightened. Refer to your user manual for specific instructions on how to tighten the chain, and how to best maintain proper chain tension during use. The chain should never be allowed to sag from the bar, and should not be able to be pulled more than 1/2 and inch off of the bar at any time. Always make sure to wear protective gloves when servicing the chain and when pulling it to check the tension.


If the tensioner on your saw breaks, you may lose the ability to control the tension of the chain. Chain tension fluctuates due to heat created from use. It is very important that your tensioner be working properly at all times, as the chain tension will need to be adjusted regularly. The tensioner may start moving freely if the screw becomes stripped. To inspect the tensioner, remove the chain cover. Next, remove the tensioner itself and inspect the screw and tension gear. These parts are easy to access, and it will be fairly noticeable if the tensioner is broken. If a new tensioner is required, refer to your user manual for the proper replacement part number.

Guide Bar or Chain

A damaged bar or chain may cause the chain to come loose from the bar and can be very dangerous when operating the machine. The bar has a groove around its outer edge, and the chain has teeth that run slightly inside of the bar rails to keep the chain moving straight. To inspect your bar, remove the chain cover, chain and bar. The rails around the perimeter of the bar should be clear of any debris. The common form of wear is the groove of the bar wearing wider. As the groove gets wider the chain is allowed to tip side to side while in use. The bar may need to be replaced altogether. The bar will wear down from regular use, as it takes quite a bit of abuse with the chain constantly spinning around it at high speeds. Ensuring your chain oiler is in proper working order at all times can help lengthen the life of your bar. Refer to your user manual for more information on how to maintain your bar, and how to tell when it is time to replace the bar. If the chain itself has broken teeth or does not fit back into the rails once it has come off, it will likely need to be replaced. Some chains can be repaired from this type of damage with a flat file. It is important to ensure that the chain fits snugly inside of the bar and that the teeth that keep it from running off of the bar are not worn down too low. All chains will need to be replaced at some point.

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