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Stihl MS280 chain stalling help

Started by Bassniper, August 03, 2014, 06:31:36 PM

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Bassniper

Hey everyone,
I'm new to this forum and I need some help. Here's my problem. I have had this Stihl MS280 since new. I use it very little, about a gallon per year but it has always served me well and never had an issue until now. The other day we had a bad storm and a big pine tree uprooted and fell over in my neighbors yard. So he asked me to come by to help cut it up. He already had the branches trimmed off when I got there so I just had to saw the main trunk up. Not a problem.

I sharpened the blade right before I walked over. I started the saw and let it warm up. I started cutting and before long I could tell the clutch area was getting hot. I shut down the saw and checked the bar oil and it was pretty low, almost empty to be exact. I honestly have never run out of bar oil before. This was a first.  So I filled it up in hopes I did not do any damage.

Back to cutting and the chain starts to stall in the middle of a cut with no pressure on the blade. Motor is running at a good RPM but the blade stops with the motor still running at RPM.

I immediately thought I burned up the clutch but upon inspection the clutch "looked" ok to me. The end bell doesn't look worn out either.

I was hoping a new clutch would solve the problem. If you think this is the problem, how do I remove the clutch? I removed the spark plug and rotated the crank shaft and pushed in a small rubber hose and tried to remove the clutch but could not break the clutch free. Seems I did not get enough rubber tube in or it was too soft and still allowed the piston to reach TDC and it still made a full rotation.

Any help would be greatly appreciated. I was hoping I did not have to bring the saw in. I like to repair things when I can. Thanks in advance.

Fifelaker

 Without seeing it I would guess oiler or brake band. To remove the clutch I leave the spark plug in and use  impact on the nut. They are left handed threads so backwards is the direction to go. To tighten it I get it as tight as I can with a ratchet, start it up, go full throttle and hit the chain brake.

isawlogs

 I was also thinking brake band....
Have you cleaned the bar and made sure oil is getting onto the bar ???
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

Bassniper

Hey guys. Thank you for taking the time to help me. It is appreciated.

The bar itself is very clean. Do either of you think, without seeing it of course, that the clutch may not be the problem? I need to find the schematics for locating the oiler and the brake band. How could I test both of these parts to see if they are doing their job correctly? I know you should be able to check the bar oiler by revving up the motor and watching for oil to spray out from the tip of the bar. I assume the oiler is still working because the night before the trouble started I did check bar oil when I cut down a pine tree leaning towards my house. It was half full if bar oil and the next day it was empty when the trouble started.

It did not take me long to figure out something was wrong and I shut the saw down as soon as I realized my saw never did this before. The blade was hot. The clutch area was hot. The chain was hot. I did check chain tension and the blade was looser than when I started because the chain was so hot and it must have expanded. Not normal hot either, very hot.

So to recap, the motor was running fine. The chain started to literally stop in the middle of an easy cut with no pressure on the bar and chain. The motor was still going strong. That why I thought I burned up the clutch. It was trying to grab under RPM but was slipping thus stalling the chain.

Is replacing the blade band and or the oiler hard to do? By the way, I was always the son helping my father fix everything growing up while my brother was playing sports. Fixing things correctly is part of who I am. I just don't want to open a can of worms I can't handle.  I'm hoping I can handle this.

thecfarm

Bassniper,welcome to the forum. I suppose the chain will spin on the bar by hand? Put a glove on before trying to move the chain. Could be the nose on your bar is bad. Sounds like you have not used your saw alot, could be the clutch,but I sure don't know.
I have run my saw out of oil a few times. Never does it much harm. Sometimes I may have to get the chain moving by hitting a log with the chain.
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

luvmexfood

It could be something as simple as the nose sprocket having gotten a lot of small fibers in the groove. As mentioned above see if the chain will turn by hand. Remove it and clean your bar groove good and check that nose sprocket. If it will not turn I usually have luck sitting the opposite end of the bar on the ground and use my scrench to hook on the sprocket teeth and turn them till all the fiber is out.
Give me a new saw chain and I can find you a rock in a heartbeat.

Bassniper

Hey guys,
Just checked the chain. It spins freely, no glove needed and the track and wheel are very clean. No wood fibers at all.

isawlogs

  Check and make sure that the chain is on the sprocket. I have seen it before.
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

Bassniper

Yes, the chain is on the sprocket and spins great.

JohnG28

Could be some junk in the wood you're cutting,  rock, metal, etc. That's dulling the chain really fast.
Stihl MS361, 460 & 200T, Jonsered 490, Jonsereds 90, Husky 350 & 142, Homelite XL and Super XL

Bassniper

Just a little more about me. I'm a journeyman cabinetmaker for 26 years now. I definitely would know if my saw hit a nail. I deal with cutting blades all day long and from time to time we hit a brad nail. The tree was suspended and not in the dirt. I don't do that with my saw and my chain is razor sharp.

Ianab

I think you are right about the clutch being the problem. It may not be worn, but it could be sticking. There should be springs that hold the clutch plates "in" and away from the sprocket.  If the mechanism gets plugged up with a bit of dust and corrosion, then the clutch plates wont move freely, and engage properly as the engine revs up. On a saw that's not used much it's probably this, rather than being worn out.

Not sure on the exact disassembly on a ms280, but there is usually a REVERSE threaded nut holding things together, and you have to jam the cylinder in place to undo it. One method is to feed a rope into the spark plug hole to block the piston. This then lets you undo the nut and get the whole clutch assembly apart. You may need some sort of "puller" to get things apart. Clean everything up, rough up the clutch plates, and put it back together again.

Ian
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

luvmexfood

I don't have a lot of knowledge but looks like you went through everything else. I agree with Ian. Bout the only thing left is the clutch.
Give me a new saw chain and I can find you a rock in a heartbeat.

Grandedog

     Howdy,
   If your saw is still making R's and the chain stalls, it's the clutch / drum issue. The clutch drum comes off easy. There is just an e-clip that holds it on. There might not be anything wrong with the clutch or the drum, they just might be glazed from slipping. Take the drum off and look at the area where the clutch engages it. If you see yourself like a mirror, it's glazed. You can easily take some emery cloth and rough it back up again. Rough up the drum, and clutch shoes by rubbing perpendicular to the clutch travel. Through some grease on the bearing, and put it back together.
Regards
Gregg
Gregg Grande
Left Coast Supplies LLC
1615B South Main Street  Willits, CA 95490
888-995-7307  Ph 707-602-0141                   Fax 707-602-0134  Cell 707-354-3212
E-Mail  gregg@leftcoastsupplies.com   www.leftcoastsupplies.com

Bassniper

Ok. I think we narrowed it down to glazed over clutch pads and end bell. I tried removing the clutch by removing the spark plug and stuffing a rubber tube into the cylinder but this did not work. The rubber tube must have compressed just enough to let the motor turn over past top dead center. What else can I stuff in there as not to scratch the cylinder wall? I was thinking of that $8 colored braided rope from Home Depot. The fake mountain climbing rope type, non nylon material.
I'll try with this material. If you have any other suggestions and or advice on removing the stock clutch I'll be checking back. Obviously it's a left handed assembly.
Once done, possibly Thursday, ill reply back. Thanks Gregg for giving me the extra boost to try it again.

JohnG28

Does this saw have an inboard or outboard clutch?  If it's an inboard, then as Greg said the clutch drum would come off by removing the e clip. This would allow inspection of the drum. To the remove the shoes, or entire clutch if outboard, then you'll need to block the piston with something more than rubber.  Like Ian said, a little rope, something the similar in diameter to the recoil rope with a knot tied in the end will work. Make sure to advance the piston to near TDC and be careful not to get rope or anything else into the ports.
Stihl MS361, 460 & 200T, Jonsered 490, Jonsereds 90, Husky 350 & 142, Homelite XL and Super XL

Grandedog

     Howdy,
   This is what your set up looks like. You don't need to remove the clutch itself to deglaze it. Just as a side note, don't start your saw with the drum removed.
Regards
Gregg
Gregg Grande
Left Coast Supplies LLC
1615B South Main Street  Willits, CA 95490
888-995-7307  Ph 707-602-0141                   Fax 707-602-0134  Cell 707-354-3212
E-Mail  gregg@leftcoastsupplies.com   www.leftcoastsupplies.com

Bassniper

Hey guys.  Thanks to everyone for giving me help. I removed the clutch and drum and it was glazed over. Emery paper did the truck followed by a good wiping with thinner. Put it back together, adjusted the chain and two things I found out.
1. When removing the spark plug cap, the lead wire from the magneto came out of the rubber boot. It appears that this is made to do this, the wire bend on the end just touches the spark plug coil. Interesting design as I thought I broke it off. Stuck it back in and it fired right up. This must have been done because they do not give you much lead wire coming off the magneto so it would be hard to pull the coil boot off without damage. I might be wrong.
2. I did need a new chain. I sharpened the original chain past the point of no return over the years. The kerf cut was too close to the thickness of the bar, thus some friction when cutting. Once a new blade was installed, it cut like new.
I will be buying a new bar as soon as I can find one and my bills cool down a bit here at home with the kids and school. From the heat it appears to have burned off some bar paint, thus weakening the steel.

Thanks everyone for all your help. It is appreciated. Work safe. Greg

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