iDRY Vacuum Kilns

Sponsors:

Chainsaw clutch help

Started by motors656, July 21, 2013, 10:12:39 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

motors656

i have a stihl 028 that fires up good and has compression, however when i try to cut a log it bogs down and the chain comes to a complete stop even when i get on the throttle. when i remove the saw from the wood, the chainsaw recovers and goes back to the high rpms
is this a clutch problem?? or a bottom end problem?

beenthere

Look at the clutch and see if all the springs are intact and doing their job. At least I think that might be the problem.
Maybe clutch pads are worn.
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

Ianab

Does the engine loose revs, or the engine keep revving and just the chain stops?

If the engine is still running at normal revs, and the chain slows down, then it's a problem with the clutch. Worn out, gummed up, jammed springs etc.

If the engine looses revs under load then it's more likely a fuel or carb problem. Be careful there because if it's starving of fuel it will be running lean (Revs high, but no power) This causes it to run hot and eventually melt. So if that's the case don't try running it until it's fixed.

Clarify which one it is and we can go on to the next step.  :)

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

nk14zp

Hows the chain and chain brake.
Belsaw 36/18 duplex mill.
Belsaw 802 edger.
http://belsawsawmills.freeforums.org/

motors656

the previous owner had been cutting down a tree when the chains caught in the middle of the log and he could not get it out. i took off the cover and the clutch its self is blue from overheating. chain and break are fine, and the saw starts up good still, no funny noises,
the chainsaw begins to loose rev fast once i begin to cut.

joe_indi

Sounds like you should also check for a worn  sprocket.
If its a spur type have deep grooves formed in the teeth?
If its a rim type is it moving a round too much and have marks started forming on the clutch drum from the impact of the bottom of the drive links.

nk14zp

Maybe the bar got pinched by the PO it sounds like a bar/chain issue not a clutch issue if the engine bogs.
Belsaw 36/18 duplex mill.
Belsaw 802 edger.
http://belsawsawmills.freeforums.org/

CTYank

Quote from: nk14zp on July 21, 2013, 11:25:22 PM
Hows the chain and chain brake.

The silence is deafening on this, most important, question. It is a CHAINsaw after all.

Is the chain sharp? Just HOW sharp is it? Does it toss chips, or dust?

We'll cover depth gauges next time.
'72 blue Homelite 150
Echo 315, SRM-200DA
Poulan 2400, PP5020, PP4218
RedMax GZ4000, "Mac" 35 cc, Dolmar PS-6100
Husqy 576XP-AT
Tanaka 260 PF Polesaw, TBC-270PFD, ECS-3351B
Mix of mauls
Morso 7110

motors656

bar and chian are completely fine, and i wouldnt know how to awnser that question as i cant seem to use the saw to see whether it tosses chips or dust.

JohnG28

I assume it will rev freely at WOT out of the cut, correct? And in the cut the chain and engine both slow down, or does the engine still rev while the chain stops?  If the previous owner beat on it bad on that tree there may be more damage than the surface shows. If the engine and chain both slow in the cut then I don't think this is a clutch issue, a clutch issue would most likely allow the engine still rev but the chain would stop.
Stihl MS361, 460 & 200T, Jonsered 490, Jonsereds 90, Husky 350 & 142, Homelite XL and Super XL

Vance in AK

Basic I know, but also check to see how dirty the air filter is...
I'm thinking fuel or air problems.  A dull chain generally won't get enough bite to pull down the motor, & if it's a pinched bar rail it should show up when you try & spin the chain by hand (saw not running ::)).

JohnG28

Quote from: Vance in AK on July 25, 2013, 06:30:46 PM
Basic I know, but also check to see how dirty the air filter is...
I'm thinking fuel or air problems.  A dull chain generally won't get enough bite to pull down the motor, & if it's a pinched bar rail it should show up when you try & spin the chain by hand (saw not running ::)).

+1 Check on the spark screen also if it has one.
Stihl MS361, 460 & 200T, Jonsered 490, Jonsereds 90, Husky 350 & 142, Homelite XL and Super XL

Vance in AK

Quote from: JohnG28 on July 25, 2013, 09:18:29 PM


+1 Check on the spark screen also if it has one.
[/quote]

Another good idea...

motors656

the screen and filter are clean, i took apart the covers and there doesnt seem to be anything broken inside

nk14zp

Oil tank full?  Proper premix?
Belsaw 36/18 duplex mill.
Belsaw 802 edger.
http://belsawsawmills.freeforums.org/

Al_Smith

Could be a number of things like the bearing missing in the clutch drum .I know that sounds silly but I've seen it .

JohnG28

Does the saw get up to full throttle and spin the chain if you're not trying to cut? If so, does the chain stop immediately after you let off the throttle? It should spin freely and "coast" a little after you let off.
Stihl MS361, 460 & 200T, Jonsered 490, Jonsereds 90, Husky 350 & 142, Homelite XL and Super XL

Oliver1655

Saw was loaned out?  I would check the high & low jets/screws to see if the borrower might have tried adjusting the carb for you.  Rule of thumb I was taught is to screw the jets all the way in then back them out 1 turn each & then with saw running adjust from there. I have found on several occasions good intentioned folks try to adjust the carb or idle & turn the wrong screws and well ---
Another problem I have came across with my Stihl S-08 is the vent screw was not allowing enough air to pass & the saw would bog down. I was in a hurry & let a saw shop replace the fuel & vent lines while I was having a couple of loops of chain made.  They had a relatively new employee who did not realize instead of screwing the set screw into the line, you just pushed it so the set screw doesn't cut into the line & can allow some air to pass.  So you might check to see if the vent for the fuel tank is working.

John
John

Stihl S-08s (x2), Stihl S10 (x2), Jonsered CS2139T, Husqvarna 338XPT California, Poulan Microvibe XXV, Poulan WoodShark, Poulan Pro 42cc, McCulloch Mini-Mac 6 (x2), Van Ruder Hydraulic Tractor Chainsaw

sablatnic

The chain could have jumped out of the spur sprocket, have you checked that too?

sawdusty1

Have you measured the compression?  Should be at least 150 to 180.
Woodmizer LT15
Husqvarna 550xp
Husqvarna 372xp
Husqvarna 350
Husqvarna 55 Rancher
Husqvarna 181se
Kubota L4701

Vance in AK

Find your problem yet motors656?

Thank You Sponsors!