Experienced gardeners share their insights in answering this question :
Burrs are often created on the chain drive links (the part that goes into the bar groove) when the chain comes off at speed. Use a file on the flats (sides) to remove them. HTH
I have pinched saws and bars in standing 100+ feet tall Fir trees and have yet to bend a bar. If properly tensioned and no burrs, inspect the chain sprocket for excessive wear.

How to Identify and Fix Common Gardening Problems ?

We provide a variety of viewpoints on how to identify and fix common gardening problems. Our sources include academic articles, blog posts, and personal essays from experienced gardeners :

Check for any debris around the bar and make sure it`s not worn down. If it is, you`ll notice that the rails are shallow. If that`s the case, it will need to be replaced. You will also want to make sure your chain oiler is in good order and that the chain itself does not have any broken teeth.
There are three main reasons for a chain to come off: Incorrect bar and/or chain for the saw; check to be sure that you are using the proper chain pitch, gauge and number of drive links to match the guide bar. Chain not properly tensioned; It is normal for a new chain to stretch and require frequent adjustment.
Your chain might simply be too old or can stretch over time. When this occurs you need to replace it. Consider that your loose chain also may be due to operator error. Exceeding the recommended gear range for the rear derailleur on your bike may lead to a droopy chain when you ride in these gears.
Generally speaking, the chain should be a little loose on the chain saw guide bar, but not loose enough that the drive links come out of the bar nose. The bar links should feel like they are raising up, but not actually come out of the guide bar. Testing the tension of the chain is a fairly easy task.
Saw chain that is too tight can prevent the chainsaw from turning the saw chain or cause the chainsaw to heat up. In addition to being a potential fire hazard, an overheated saw chain and guide bar can significantly reduce the useful life of these components.
Today, McCulloch offers a complete line of garden products: powerful chainsaws, sturdy trimmers, lawnmowers, garden tractors and hedge trimmers.
Don`t Cut Into Dirt

But when you cut close to the ground, you`re just begging for a quick dip into dirt, rocks and crud. All it takes is a second in the dirt to dull the cutters. In addition to dulling the cutters, dirt also wears out the chain links faster, causing the chain to stretch.

If the chain is too loose, your run the risk of the chain coming off the guide bar completely, which may cause severe injury to the user, including a loss of limbs or digits or even a severe cut to the face. Kickback is also a serious issue with loosely tensioned chain saw chains which can cause severe injuries.
The most probable – and easiest to fix – cause of chain rotation while the chainsaw engine idles is a poorly adjusted idle setting on the carburetor. The result is that too much fuel is delivered to the combustion chamber when the throttle is released, and the engine doesn`t really slow.
Today, McCulloch offers a complete line of garden products: powerful chainsaws, sturdy trimmers, lawnmowers, garden tractors and hedge trimmers.

Discover Relevant Questions and Answers for Your Specific Issue

the most relevant questions and answers related to your specific issue

The chain keeps coming off and we just got it today.
ANSWER : Sounds like you do not have the chain tight enough. Read the book if it came with one. Good luck

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Chain keeps coming off – Poulan Wild Thing 2375 18" Gas Chain Saw 2.5 Cuin
ANSWER : Open the chain guard.Once there look for a bolt that hold the chain plate.The chain plate has a large groove and the bolt.djust the chain by plull to the front until the chain is tight,but not too much,just test by hand if is move freely but tight.Reverse the procedure.If you need more help come back.Post / thumbs / testimonial are welcome!

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My 18 Inch chain saw will not keep oiling the Chain, I had it worked on and He said it was plugged. How do you unplug it with out taking it all apart. Is there a spot to blow air through. the Preacher..
ANSWER : Remove the chain bar and look just below the bolts holding it in place. You’ll see a small hole where the chain bar oil pump pushes out oil. Make sure this hole is clear then run the saw without the bar on.

Be CAREFUL of fingers!

You should see oil coming out of that hole. If not, you may need more serious work done with the saw (chain bar pump replacement).

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Will only run on choke – McCulloch 16 Inch Gas Chain Saw MCC1635AK
ANSWER : Its running too lean, start with easy stuff first, replace the fuel filter in the tank, check the condition of the fuel hose up to the carb, any signs of damage or leak, then replace.

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I have a McCulloch Chain saw model 3516. The male threads to the chain oil resevoir is cracked. How do I fix it?
ANSWER : A auto parts store will have a oil resistant epoxy

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Dont know what type off oil to put in the bar and chain tank on the chainsaw
ANSWER : Hi and welcome to FixYa, I am Kelly

All Bar oils are SAE 30W non-detergent oil. Go down to the local auto parts supply and buy the cheapest SAE 30W you can find…. SAE 30W is SAE 30W regardless of what brand is on it and for bar oil it is not an issue.

Thanks for choosing FixYa,

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<!– from fixya rte –>How full should I fill the chain oiler – McCulloch 16 Inch Gas Chain Saw MCC1635AK
ANSWER : Fill it all the way. I fill mine every time I put fuel in the saw to keep from running out and burning up the chain.

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Ake 40 18s chain keeps coming off when in use
ANSWER : The only time I saw this was when the saw was run with the chain too loose. The chain should be snug al the way around the bar. If it is run loose for too long the chain will develop burs on the driver links. Now the driver link will not fit in the groove on the bar so the chain is tossed off. Replace with a new chain

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