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I have seen the drive coupling on these units get worn out (stripped) by the driveshaft, and need to be replaced . This part threads on the end of the crankshaft outside the engine housing on units that don’t have a clutch. It could be your problem if you installed a new driveshaft.
How to Identify and Fix Common Gardening Problems ?
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If the trimmer head doesn`t turn, the first place to look for problems is around the head itself. It may be restricted by stringy plant stems and roots — they may be wound so tightly that you have to cut them off with a knife. It`s also possible that the engine isn`t developing enough power to spin the head.
Worn clutch – Since the string trimmer clutch engages with one or more drive shafts attached to the trimmer head to rotate the head when the throttle trigger is depressed, a worn-out clutch may prevent the trimmer head from spinning. A new clutch assembly is relatively inexpensive and easy to install.
If the drive shaft is broken, the string trimmer head won`t spin. The drive shaft is not repairable—if the drive shaft is broken, you must replace it. Need help finding your model number? If the threads on the drive shaft are stripped, the trimmer head will not stay on the shaft.
Checking for debris or damaged blades: Visually inspect the blades and confirm there is no debris stopping the blades from moving. If there is debris ensure the machine is powered off when removing any blockages. Check the blades for any damage as a damaged cutting blade could cause the machine to stop working.
Fixed head systems use individual lengths of line that are loaded or threaded into the trimmer one at a time as needed. This avoids some of the hassles of winding line onto trimmer heads and makes the overall process of dealing with trimmer line less cumbersome.
When your trimmer starts and runs on choke, it could be because the check valve in the gas cap is clogged. Start the trimmer and gently unscrew the gas cap halfway off. Turn the choke off and assess. If the engine is still running, that means the gas cap may be the culprit.
It is possible that your shaver does not turn on or move because it is dirty. There can be hair or dirt particles stuck inside it, causing the shaving heads to be blocked. To fix this problem, properly clean your shaver. If possible, remove the shaving head and clean your shaver from the inside as well.
If you have confirmed that your Philips Nose Trimmer has a full battery and it is still not working, then it may not be working because it is dirty and the cutting unit is blocked. We advise that you clean your nose trimmer after each use for optimal performance.
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…the motor runs but head won’t move.
The head drive is probably craked or stripped or the driver is broke, to check this, remove the head and inspect, these replacement parts normally are pretty cheap.
Just bought a brand new Husqvarna 224L Trimmer.
Started it up and it runs fine.
But the trimmer head will not turn. It just makes a grinding noise.
The manual that came with the trimmer is useless. It says to use the spanner wrench that is included but it doesn’t fit the nut. The nut fits into a hex hole inside the head itself.
Out of the box I can turn the head easily without the motor running.
Please tell me that there is an adjustment and not something defective.
Hi, take it back to the dealer as the powered or gear box have not been fitted correctly. The noise you can hear is most likely the clutch drive grinding on the drive shaft. Hope this helps, regards Phil.
Engine runs, blades turn but mower will not move
Look in front of back tired on frame, not deck, there are. 2 rods, 1 on each side, rods look like a L, it’s going through a little eye opening, push it backards, mower should move. If rod is pulled through opening and locked in, mower will not move..its a safety. Feather on mower
Lawn scarifier motor runs slow than starts to smoke
What sort of scarifier is it?
Safety switch on brake handlechecks ok but motor cuts off when released
Check clutch safty switch or seat safty got to be one of those switches
How do I replace the old head with a new one?
Your old head should simply unscrew from the gear box. You should not have to disassemble the head to get it off. Some models have a small hole above the gear box where you can insert a small screwdriver to lock the drive shaft so that the entire unit stops spinning. Keep in mind that some models have left-hand threaded heads while others have right-hand threaded heads. In most cases, you’ll unscrew the head opposite of whichever way the head normally turns while you’re trimming. This is by design so that the machine doesn’t unscrew the head itself while you’re using it. You can find replacement heads for most makes and models of trimmers at PartsBuggy.com.
Trimmer runs but the head wont turn – Craftsman Convertible 25cc. Gas Line Trimmer
It may be that the drive shaft is broken, or not engaged to the engine. Make sure the trimmer attachment is locked all the way onto the shaft coming from the engine. If it still doesn’t work, check by seeing if any of the other attachments work when you put them on. If they do, you know the drive shaft in the trimmer attachment is probably broken.
I need to replace the whole trimmer head and I dont know how to get the gear case off so I can put the new one on. Can anyone help?
To replace the trimmer head you don’t need to replace the gear case. If you look closely about a 1/4 inch up from the safety guard you’ll see a hole in the side of the “gearcase” assemby. (you may have to clean the old dead grass clippings off to see it) You can shove a rod into the hole that will stop the head from spinning freely and I believe you spin the head clock wise (reverse threads) to remove the head.