How-to on greasing a Stihl clutch bearing?

[steved]

I lightly searched, found a batch of threads saying how often guys grease the clutch bearing and what to use, but is there a method to actually accomplishing the task? I've had my 391 for four years now, never touched it other than oil and gas (maybe 25 cords of firewood)...probably something I should do.

What's the method? I'm not in front of my saw right now, so...

 

[hotshot]

I lightly searched, found a batch of threads saying how often guys grease the clutch bearing and what to use, but is there a method to actually accomplishing the task? I've had my 391 for four years now, never touched it other than oil and gas (maybe 25 cords of firewood)...probably something I should do.

What's the method? I'm not in front of my saw right now, so...

Husky IOMs state weekly, but that's over kill unless it's used five days a week, 8 hours a day.

See pages 33 & 35 of the attached file. I use moly grease (sparingly) & not engine oil, as
they do give oil as an option. I've never seen a Stihl manual reference weekly lubing, but a needle bearing
is a needle bearing, and not saw specific.

You have to remove the clutch drum to properly clean & relube the bearing & drum race.

 

[2dogs]

Pop off the e-clip and washer. Remove the sprocket and replace as needed. Remove the drum and clean it, replace as needed (is it blue or warped or worn thin?). Pull off the bearing , clean and repack with grease. It only takes a small amount, maybe half the size of a pea. Put it back together in reverse order.

It is a good idea to have an extra clip on hand. They tend to fly off if given half a chance. Wear safety glasses and cover the clip with a rag as you reinstall it.

 

[steved]

Awesome, that sounds like a fairly easy thing to do. I will definitely get it done before I put the saw to use again.

 

[Russ Melampy]

I burned a bearing up this summer on my 441 RCM while noodling a 225 year old ash, clogging up the clutch area major... and was told by a mechanic to not grease it, but just make sure it is getting oiled as used. so now when I noodle I make sure to not clog it up like I used to...so far so good

 

[2dogs]

Getting oiled as used? How does that happen?

 

[hotshot]

Getting oiled as used? How does that happen?

I think he means from the bar oil that gets on the chain, but that's hardly
controllable when you're cutting for a few hours in dry dead wood...

 

[1Alpha1]

I burned a bearing up this summer on my 441 RCM while noodling a 225 year old ash, clogging up the clutch area major... and was told by a mechanic to not grease it, but just make sure it is getting oiled as used. so now when I noodle I make sure to not clog it up like I used to...so far so good

Care to elaborate some on the "getting oiled as used" statement?

I could be wrong, but I've never heard of a clutch bearing getting lubed by the bar oiler.

 

[User Name Here]

Care to elaborate some on the "getting oiled as used" statement?

I could be wrong, but I've never heard of a clutch bearing getting lubed by the bar oiler.

You're right. There isn't a way that a clutch bearing can get any appreciable amount of bar oil from the oiler. You need to make sure you check it every so often. i usually look at it and grease it about every 2-3 sharpenings. Has worked fine for me, but I'm not a commercial user either - just a weekend warrior.

 

[Russ Melampy]

well it sounds like I need to grease my bearing then...I was told (after I replaced my burnt up bearing) to just keep it clean, the oil from the oiler will be enough and it will live forever. So then, what grease do you guys like for that? I wonder how long my bearing would live without me adding any grease to it...I probably have 10 hours on this new bearing since being replaced in June

 

[1Alpha1]

well it sounds like I need to grease my bearing then...I was told (after I replaced my burnt up bearing) to just keep it clean, the oil from the oiler will be enough and it will live forever. So then, what grease do you guys like for that? I wonder how long my bearing would live without me adding any grease to it...I probably have 10 hours on this new bearing since being replaced in June

I just use wheel bearing grease. I have a can of Valvoline that I've had for years.

I'm not a commercial cutter either, so when I grease the clutch bearing, it lasts me quite a while. I do it about 2-3 times a year.

 

[1Alpha1]

well it sounds like I need to grease my bearing then...I was told (after I replaced my burnt up bearing) to just keep it clean, the oil from the oiler will be enough and it will live forever. So then, what grease do you guys like for that? I wonder how long my bearing would live without me adding any grease to it...I probably have 10 hours on this new bearing since being replaced in June

You're okay with only 10 hrs. on that new bearing.

But....now you know better. That's just one thing I love about this forum. All the BS gets separated from the facts rather quickly.

 

[steved]

I will take mine apart next weekend...looks like I will have some home time after all...

 

[Wood Doctor]

Needle bearings always amaze me at how long they can last between lubes. But, even they require attention now and then. I've replaced several clutch bearings on customers' saws. One guy let his saw chain almost carve right into one of them, right through the rim sprocket and the spline. I lube them whenever a saw makes it to my bench for service. It's amazing what you run into.

 

[Russ Melampy]

gonna check all my saws. thanks guys

 

[steved]

Needle bearings always amaze me at how long they can last between lubes. But, even they require attention now and then. I've replaced several clutch bearings on customers' saws. One guy let his saw chain almost carve right into one of them, right through the rim sprocket and the spline. I lube them whenever a saw makes it to my bench for service. It's amazing what you run into.

I always look at the needle bearings in a UJoint on a pickup...I ran 450hp and nearly 800lb-ft through the ones on my Dodge for over 250k. The kinda umph some of the other diesel nuts were running should crush the needles...

 

[Russ Melampy]

so I greased the bearings on all three saws yesterday, and I seriously can't believe that I believed my mechanic...I was noodling when the bearing failed, so the assumption was that the noodles were absorbing all the oil and that caused the failure. So I had been making sure to keep it unclogged when noodling this summer and thought I learned a lesson. Wow. I'm very glad someone posted this thread. I would have learned the truth eventually (when other bearings failed), but this way was better! What else am I neglecting? jeeesh...

 

[Deets066]

The bearing only gets used when the saw is idleing

 

[1Alpha1]

The bearing only gets used when the saw is idleing

That is true, but what concerns me, is the amount of heat that the bearing is subject to.

The heat is what breaks the grease down prematurely.

 

[Philbert]

I was told (after I replaced my burnt up bearing) to just keep it clean, the oil from the oiler will be enough and it will live forever.

That works on the bearings in bar nose sprocket, but not a drive sprocket.

I learned about drive sprocket bearings 'the hard way' - one day looked down and saw bits of the plastic cage sticking out. Now I clean and grease them whenever I have the sprocket off for cleaning. I wipe off the old stuff, then press in a little dab of white lithium grease from the inside with a toothpick. Pretty easy to do on a STIHL with an inboard clutch/outboard sprocket. I have a little toothpaste like tube of the 'official' STIHL grease that is convenient and lasts a long time.

Husqvarnas are a little different with outboard clutches/inboard sprockets. My 353 has a hollow spindle on the clutch side, and a small hole through the side, which lets me pump grease in through the end to the bearing without disassembling the clutch. But I can't wipe off the old stuff, so I am cautious about pumping in too much.

Philbert