I put a little extra oil in my mix but I was told it wont hurt anything. Maybe fowl a plug. I mix mine in old gallon jugs so its not exact and I just want a margin for safety. I better check my info. Thanks 👍
Buddy took my 271, which dropped the clutch bearing and melted everything. Oil pump is cooked, case and cover all got really hot. Lesson learned, don't loan out expensive tools. He said the chain got looser and it smelled like burning plastic, but he kept running it anyway, until it locked up. Just siezed due to melted plastic locking up the brake and clutch. My only issue is finding oem parts. The local repair shops are idiots, and not touching my saw, but it's hard to fix it without access to stihl parts.
Sounds like your buddy inadvertently hit the chain brake while running the saw at full throttle. The 271’s engine is more powerful than the brake and will keep going with the brake on while holding down the trigger, hence creating enough heat to melt the needle bearing, dust cover, oiler and the case. I have seen this happen 5 times this year with people who bought the 271 as their first saw. While cutting they felt the saw “bog” and thought they needed to just give it more gas and work through it when in actuality they were fighting the chain brake and melting their saw. Unfortunately this damage is not covered under the warranty and is considered “customer damage”.
The brown and black deposits on the piston either look like its been burning bar oil, (somebody filled the tanks wrong, and than didn't get all the bar oil out when they realized their mistake) or just running old shitty gas.
Ya. I agree with you. If it was over heated you would have bluing on the piston an cylinder. All that black tar looking crap is oil. An there was no sign s of the cylinder fins being plugged up with crap. I would just put a farmtec cylinder an piston in it an call it a day. Iv had good luck with there upper cylinder parts .
Hi Jason, next time I need to tear one down I will record it. Off the top of my head I am thinking plastics, handle and carburetor. Then the 4 bolts that hold the cylinder on.
Here's a thorough demo in German, it's the only one I could find for MS291/MS271 ua-cam.com/video/HLpBHAGnLfg/v-deo.html . Unfortunately it wasn't successful and I don't know why he gives up and uses another saw.
I have a Stihl MS261 C-M which I am told by the workshop that it has overheated, it is just 2 months out of warranty, I can assure you that the fuel/oil mixture is correct as I am very particular about this. Currently they are waiting for an answer back from Stihl, but I guess they will blame me not anything to do with the saw. Stihl website states that as it is a commercial saw, they expect that it should last for 5 1/2 years, I am only using it for domestic firewood, and it has hardly been used, I have been trying to find out if anyone else has had a similar problem, could it be a fault with the saw. Fortunately in Australia our consumer rights are very strong, but I hope that I don't have to go down this path. If anyone knows of this happening to others would appreciate some information to follow up on.
I have seen this condition occur many times. That "varnish" is called "plating" and caused by the oil getting so hot it plates out and binds onto the piston and cylinder. It also occurs when the chosen oil is not adequate for the manner an engine will be used. Tuning too lean can cause this to occur as it causes an engine to run hotter. There are also some brands of two stroke oil that are "dirtier" than they should be, encouraging oil plating. That engine could self clean itself if provided a 40-1 mix of Stihl HP Ultra and allowed to run cool in a "no load" state for 6 or 8 hours. That process would clean out the plating and unstick the piston ring.
What about after market parts? Rebuilding it myself as a learning project? I believe mine was damaged due to my son running it with a dull chain. Trying to finish what he was doing… the saw has few hours on it but that last bit he did, done it in.
Right!! It has been a while since I worked on that saw so I watched my video again. I am sure the customer added some extra 2 stroke mix to the gas to try to get the saw running again.
Would a Stihl ms291 top end fit it? Or is it better just to hone it yourself- got the exact same thing going on. New Cylinder/piston kit is about $250- so yea new saw is looking good
Kasey I am not sure. I worked on it for a customer. If I had to guess, the chain was dull. Cutting with a dull chain causes the saw to work extra hard and can cause over heating.
@@bennyhaha43 no. There would be more scaring than burn. Plus, look at the rings. They look fine compared to rings that had zero lubrication. I'm in the process of repairing my ms271 from running straight gas and the piston is shiny with plenty of scoring and the rings are quite worn.
I put a little extra oil in my mix but I was told it wont hurt anything. Maybe fowl a plug. I mix mine in old gallon jugs so its not exact and I just want a margin for safety. I better check my info. Thanks 👍
You bet.
Buddy took my 271, which dropped the clutch bearing and melted everything. Oil pump is cooked, case and cover all got really hot. Lesson learned, don't loan out expensive tools. He said the chain got looser and it smelled like burning plastic, but he kept running it anyway, until it locked up. Just siezed due to melted plastic locking up the brake and clutch. My only issue is finding oem parts. The local repair shops are idiots, and not touching my saw, but it's hard to fix it without access to stihl parts.
Have you searched online? eBay? And yes I agree, only OEM parts.
@@small_engine_repair I have, and certainly found a lot of knockoff stuff. I'll find it eventually.
Sounds like your buddy inadvertently hit the chain brake while running the saw at full throttle. The 271’s engine is more powerful than the brake and will keep going with the brake on while holding down the trigger, hence creating enough heat to melt the needle bearing, dust cover, oiler and the case. I have seen this happen 5 times this year with people who bought the 271 as their first saw. While cutting they felt the saw “bog” and thought they needed to just give it more gas and work through it when in actuality they were fighting the chain brake and melting their saw. Unfortunately this damage is not covered under the warranty and is considered “customer damage”.
The brown and black deposits on the piston either look like its been burning bar oil, (somebody filled the tanks wrong, and than didn't get all the bar oil out when they realized their mistake) or just running old shitty gas.
Yeah one of the two.
Ya. I agree with you. If it was over heated you would have bluing on the piston an cylinder. All that black tar looking crap is oil. An there was no sign s of the cylinder fins being plugged up with crap. I would just put a farmtec cylinder an piston in it an call it a day. Iv had good luck with there upper cylinder parts .
My 271 looks just like this! It’s not hard to put but it doesn’t run as strong as it should
I read your comment and not sure what you meant by "not hard to put". Did you mean, "not hard to pull"?
To bad you couldn't get the truth about how your customer burnt up this saw. That would be useful information so we don't do it to our saws.
Agree. That is why my go to first step is to pull the muffler on any job for a chainsaw.
They didn't run it in the summer with the carb shutter in winter open setting or not let it warm up before running it hard did they?
Possibly :shrug
It would have been good to empty fuel and put the correct fuel mix and run the saw.
That's the way I work...
Even with the correct fuel and oil mix this saw was not going to run correctly.
High temperature due to lack of fuel
It is always fun trying to diagnose based on scoring and color!! :-)
Good video
New subscriber
Cheers
Thanks Dave.
Yes sir you said it best OEM parts and labor cheaper to buy a new saw
No doubt!
Hi
What oil mix ratio recommended for stihlchainsaw?
Refer to the manual to be sure, but most are 50:1
Looks like maybe someone put bar oil in the gas
It's possible.
Would you please post the tear down in real time? I've got a 271 I'd like to take apart. What all has to come off to get the cylinder off?
Hi Jason, next time I need to tear one down I will record it. Off the top of my head I am thinking plastics, handle and carburetor. Then the 4 bolts that hold the cylinder on.
Are you going to rebuild or modify your saw
Robert this was a customers saw. Its been a while since I posted this video. They chose not to repair it.
Here's a thorough demo in German, it's the only one I could find for MS291/MS271 ua-cam.com/video/HLpBHAGnLfg/v-deo.html . Unfortunately it wasn't successful and I don't know why he gives up and uses another saw.
I have a Stihl MS261 C-M which I am told by the workshop that it has overheated, it is just 2 months out of warranty, I can assure you that the fuel/oil mixture is correct as I am very particular about this. Currently they are waiting for an answer back from Stihl, but I guess they will blame me not anything to do with the saw. Stihl website states that as it is a commercial saw, they expect that it should last for 5 1/2 years, I am only using it for domestic firewood, and it has hardly been used, I have been trying to find out if anyone else has had a similar problem, could it be a fault with the saw. Fortunately in Australia our consumer rights are very strong, but I hope that I don't have to go down this path. If anyone knows of this happening to others would appreciate some information to follow up on.
Any word back on what they found?
I have seen this condition occur many times.
That "varnish" is called "plating" and caused by the oil getting so hot it plates out and binds onto the piston and cylinder. It also occurs when the chosen oil is not adequate for the manner an engine will be used. Tuning too lean can cause this to occur as it causes an engine to run hotter. There are also some brands of two stroke oil that are "dirtier" than they should be, encouraging oil plating. That engine could self clean itself if provided a 40-1 mix of Stihl HP Ultra and allowed to run cool in a "no load" state for 6 or 8 hours. That process would clean out the plating and unstick the piston ring.
Thanks for all that information.
Must of used Lawnboy oil. If its hard to pull it's scored. 90 psi is horrible. What was the red cylinder gasket material? Looks like RTV.
Yeah it does look like RTV.
Was it way too rich or burning something other than 2 stroke oil...or had way too much oil in the gas??? Or way too lean
My guess it was to rich and the wrong oil to gas mix ratio.
What about after market parts? Rebuilding it myself as a learning project? I believe mine was damaged due to my son running it with a dull chain. Trying to finish what he was doing… the saw has few hours on it but that last bit he did, done it in.
You could go after market, but the quality is horrible. Stihls are worth rebuilding and worth going OEM.
i bought farmboss. they both went bad he piston
Was it out of tune?
5-1 oil mixture it looked so dark lmao
Right!! It has been a while since I worked on that saw so I watched my video again. I am sure the customer added some extra 2 stroke mix to the gas to try to get the saw running again.
What cause crankshaft break
Chain is way to tight and overtime that pressure causes parts to break.
Would a Stihl ms291 top end fit it? Or is it better just to hone it yourself- got the exact same thing going on. New Cylinder/piston kit is about $250- so yea new saw is looking good
I don't know off the top of my head. Would need to check STIHL specs to know.
The answer is no!Evry chainsaw is diffrent
WAYYYYY TO MUCH OIL
Maybe
@@small_engine_repair yea that looked way darker than 50:1
What size are the muffler nuts?
Not sure.
Usually t-27 or 10mm
@@drewhellams7894 thank you sir
Inferior oils wi varnish up the piston bad.
What oils are you referring to?
What caused it to overheat?
Kasey I am not sure. I worked on it for a customer. If I had to guess, the chain was dull. Cutting with a dull chain causes the saw to work extra hard and can cause over heating.
@@small_engine_repair isn't it more likely that they ran straight gas in it?
@@bennyhaha43 no. There would be more scaring than burn. Plus, look at the rings. They look fine compared to rings that had zero lubrication. I'm in the process of repairing my ms271 from running straight gas and the piston is shiny with plenty of scoring and the rings are quite worn.
@@bennyhaha43 this: ua-cam.com/video/zYFIwDwfYWo/v-deo.html
@@small_engine_repair 1:33 oil mix is ok ?
The piston pin rings are available
Couldn't you ball hone the cylinder walls and reassemble it. ??? FREE CHAINSAW
Yes, but if I remember correctly the customer decided not to fix the saw and picked it up.
@Small Engine Repair Dang !!
Offer a disposal service
You'll get some junk but you'll also get some jewels.
Great video BTW very informative 👍
I do run an ad on craigslist and facebook that I want small engine equipment running or not. I have scored on lawnmowers in the past.
@@small_engine_repair the cleverness of the American spirit
Props to you