Part of our complete Small Engine Troubleshooting Guide.
This is the list for a saw that runs. If yours will not fire in the first place, our guide to a chainsaw that will not start is the one you want. Work through this one in order, because the cheap answers are also the likely ones.
Do not lean on a saw that will not cut. Weight is what a sharp chain supplies for itself, and forcing a dull one heats the bar, loads the sprocket and makes the saw far more likely to grab and kick. Every extra minute of pushing turns a sharpening job into a bar and chain.
1. Read What Comes Out of the Cut
The chip pile tells you nearly everything before you touch a tool. Square chips the size of a grain of rice mean the teeth are slicing properly and the saw is doing its job. Fine powder like flour means they are not cutting at all, only scraping, and that is a dull chain or a chain that cannot reach the wood.
A cut that wanders off square is a third message again, and it points at one side of the chain rather than the whole thing. Note which of the three you have before anything comes apart, because they lead to different places and a wrong guess here costs a new chain you did not need.
2. Dull Happens in One Second
Owners assume a chain wears out gradually over a season. It can, but far more often a sharp chain is killed instantly: one touch of the dirt while limbing, a fence staple grown into a hedgerow tree, a nail buried in reclaimed lumber, or a lick of a stone in a storm-felled trunk.
So a saw that cut beautifully an hour ago and makes dust now is almost certainly not broken. Check the top plates for shine on the cutting edge, and look for one or two teeth that are visibly worse than the rest, which is the fingerprint of something hard in the wood.
3. The Depth Gauges Nobody Lowers
This is the reason behind the call we get most often in firewood season, which is that a nearly new chain already will not cut. In front of each tooth sits a small rounded lug, the depth gauge or raker, and it controls how big a bite that tooth can take.
Every time a chain is filed the teeth get shorter, but the gauges do not. Eventually the gauge stands proud of the cutting edge, the chain rides along on its gauges, and the saw makes powder no matter how sharp the teeth are. They need lowering in step with the teeth, with a gauge tool rather than by eye, and getting that wrong in the other direction makes the saw grab.
4. A Cut That Curves
If the saw pulls to one side it is cutting unevenly, and there are only two real causes. The first is tooth length. Hand filing tends to favour one side, and teeth that are longer on the left take a bigger bite than the ones on the right, so the bar steers. The fix is to file everything back to match the shortest damaged tooth, which feels wasteful and is not.
The second is the bar. Take the chain off and sight down the rails: they should be square and the same height on both sides. Splayed or unevenly worn rails let the chain lean over as it loads, and a leaning chain cuts in an arc however well it is sharpened. Our chainsaw maintenance guide covers dressing a bar and when one is finished.
5. The Oiler, the Groove and the Blue Bar
A dry bar will stop a saw cutting on its own, and it does expensive damage while it does it. The tells are smoke from the cut on wood that is not wet, a bar that feels hot through a glove, a blue or brown tint to the rails, and a chain that has gone stiff.
Check flow the simple way: run the saw at speed with the bar tip a hand's width from a light-coloured board and look for a line of oil thrown onto it. Nothing there means the tank, the groove or the oil hole. The groove packs solid with sawdust and old oil, and the small oil hole at the base of the bar blocks with the same mixture. Both clean out in under a minute, and both ruin a bar if they are ignored.
6. Backwards Chains, Tension and the Clutch
Three last things, and the first is commoner than anyone admits. A chain fitted backwards will spin happily and rub rather than cut, because the cutters are facing the wrong way. Look along the top of the bar: the cutting edges must point forward, away from the saw, along the top run.
Tension comes next. Set it cold with the bar nose held up, so the drive links stay in the groove and the chain can still be pulled round by hand, and expect it to slacken as the bar heats. Last is the clutch. If the engine revs freely but the chain slows or stops the moment it meets wood, the clutch shoes or drum are glazed or worn, and that is bench work rather than a field fix.
Matching the Symptom to the Cause
READING THE CUT
| What the Saw Does | Where to Look First |
|---|---|
| Fine powder instead of chips | A dull chain, or depth gauges that were never lowered with the teeth. |
| Cuts in a curve | Teeth longer on one side, or uneven bar rails letting the chain lean. |
| Smoke, hot bar, stiff chain | The oiler: tank, blocked groove or a plugged oil hole in the bar. |
| Revs fine, chain stops in the cut | A glazed or worn clutch, or a chain fitted the wrong way round. |
When to Call the Shop
Sharpening, lowering the gauges, cleaning the groove and the oil hole, checking chain direction and setting tension are all jobs for a bench in the garage, and between them they account for most of the saws carried in here for not cutting. A shop grind is worth it once a chain has been hand filed a few times, because it resets every tooth to the same length and gives you a straight reference to file back to.
Bring it to us when the oiler still gives nothing after the groove and hole are clear, when the bar rails are splayed or blued, when the chain slows under load on a saw that revs cleanly, or when a chain that has just been ground properly still will not cut. The same reasoning applies to a dull mower deck, which our guide to lawn mower blade sharpening covers. We will tell you plainly what it needs and quote it before any work starts.
Chainsaw Cutting FAQ
My chain is almost new and it still will not cut. Why?
Usually the depth gauges. They control how big a bite each tooth takes, and if they were never lowered as the teeth shortened the chain rides on them. It can be perfectly sharp and still refuse.
The saw cuts in a curve instead of straight. What causes that?
Teeth longer on one side than the other after hand filing, or a bar whose rails have worn unevenly so the chain leans. Check the bar before buying another chain.
Should I push harder when the saw stops cutting?
No. A sharp chain feeds itself and you only guide it. Pushing a dull chain heats the bar, wears the sprocket and turns a sharpening job into a much larger bill.
Do you sharpen chains in Richmond, KY?
We do, along with bar dressing, oiler repair and clutch work, across Madison County. Pickup and delivery is available and you get a firm quote before any work begins: (859) 661-8877.
Saw Making Dust Instead of Firewood? Get a Firm Quote First.
Honest diagnosis, fair pricing and fast turnaround from Turf & Trail Small Engine Repair in Richmond, KY. October is when the woodpile gets built in Madison County, so a chain, a bar and an oiler sorted now is a saw that works all winter.
We handle chainsaw and trimmer repair, blade and chain sharpening and pickup and delivery in Madison County. Serving Richmond, Berea, Waco and Kirksville.
Call (859) 661-8877