Great vid Sir through out, machining building etc...........................definately no commercial BS here !.................subscribed and massive like you gotta be one of the best on the you tube platform, thankyou for your time
Fella i watch named richard flagg did some testing on 2 stroke oil and stihl ultra hp failed miserably. The way he explained it,it was burnin off and not enough was staying behind to lubricate. Ive used it for a few years without any failures in my 3 saws,string trimmer or leaf blower,but im now switching to lucas synthetic land and sea. Looks like an easy saw to rebuild,so at least thats good. Hope it holds up for you
I have read that the you can remove some of the plastic ribbing on the underside of the shroud to make the flat fin cylinder fit under a slant find shroud. Did you explore this option? Do you think it would work? I’m looking to get a slant fin that was straight gassed and rebuild it and was wondering. Great video. Well done camera work. Thanks
@@dibiase9502 In my case, I had to heavily machine the cooling fins, and grind some of the case ribs. Takes about 2 hours. If you have more time than money, do what I did. I think I explain it in the video reasonable well.
The reason the cilynder doesn't fit properly is because Stihl came up with gen 2 cilynder called slant fit wich is supposed to give a couple more HP and less cooling fins in aprox. 2016-17 . The gen 2 is almost available only from Sthil and was in there saws at the time of change giving a bit of weight lost and lower profile cost lots more $$ I have the gen 1 bought in 2014 with the straight cilynder. Very nice video!!
@@123456773934 So gen 2 has more power and less cooling fins? Sounds like gen 1 was manufactured too well. Had to ensure something would fail! Ran the saw hard today, and performed very well. Switched to 42-1, no smoke so I’m going to stick with that ratio. If I ever have to rebuild again, are you aware of any aftermarket gen 2 heads?
My uncle bought 4 brand new stihl 261c mtronics and his laborers blew em all up using the 50.1 ratio. Im going to go through all of them and see if i can salvage em.
@@FastandFoody Definitely worth rebuilding if you have the time. My cheap aftermarket piston and head are holding up very well. Now running 40-1. Still runs very clean.
@@hidhshsj123 Please explain your logic. Are you suggesting it was just a bad decompression valve? I didn’t look for leakage there. I think I would have noticed air bleeding out when doing the compression test. I use the decompression valve to reduce shoulder strain.
The decompression button saves on many things. Reduces pull starter wear/pull string wear, reduces starting strain. I have a Stihl 261 and I use it. Nothing wrong with using the decompression valve. The decompression valve is awesome.
soooo many people document this. what many are finding is Honda hp2, belray hr1 and motul 800 seem to be best performers. 50 to 1 -- some like 40 to 1.
By the color of conecting rod, saw shown that , its been overheated from unproper usage. Used that same saw for 6 years right now, over 300 tanks gas used. Still runing like it should, 0 engine rebuids so far. Dont know what youre guys fucking around whit this stuff.😂❤💯
bad choice of cylinder kit! way too much cooling fin area removed. you should have bought a meteor kit. 1/2 the $ of oem kit. i did not have to do anything to the fins on the one i used for my 362. not sure on the 261, i used a hyway kit on that one. i had to remove some of the ribs on inside of cover and a small area of cooling fins. both saws i bought off ebay with blown top ends. i run synthetic at 40:1. used to run 50:1. too dicey
@@davidgoliath982 Even after removing the fins as shown in the video, there is still around 20% more cooling fin surface area on the aftermarket head than on the OEM head. Definitely going to switch to 45-1 or 40-1.
@@OldSoulMillennial ya but most was removed from exhaust side. the oem cyl. is designed in a specific way to be efficient with less material to reduce weight and cost
@@OldSoulMillennial the oem failure was not likely due to the design or the quality. it is almost always operator error. the oil may not be adequate and or the jetting was set too lean or a possible small air leak. also it is not likely that the porting in that budget cyl. replicates the oem porting that well. that has been my experience. i mean it might but........ chances are it will not have all the power it should which may not matter much depending on the type of use
@@davidgoliath982 My argument is that the failure was absolutely due to design and quality issues. I bought a professional grade saw with the expectation that it should last over a decade without needing a rebuild. I used stihl brand recommended synthetic oil. I did not adjust any carb settings until the rebuild. How can you claim operator error when I’ve followed all of stihls reccomendations. Hell, I even let the saw warm up a minute at idle prior to pushing it. I’ve always been a stihl guy, but I don’t see any excuse here.
This is an excellent example that illustrates why these saws should be run at 50:1 ratio and not a smidge richer. There is so much carbon accumulated inside that after only 2 years it destroyed the engine. And if this saw was run using the 50:1 mix, it wasn't run long, frequently or hot enough to burn off all those nasty deposits. They eventually turned to carbon, flaked off and sanded down the cylinder causing the loss of compression.
@@Steelologist Interesting theory. I have different thoughts. I only used stihl full synthetic mix oil at the pre measured 50:1 ratio. I beat the balls off this saw. It’s not a one cut and done saw, when I start this saw, I expect to be cutting hardwood logs into 16” rounds. Carbon build up unavoidable. I strongly believe 1) Stihls mix oil is crap. 2) 50:1 is too lean. Many have commented that 50:1 is just for the engines to meet epa emissions. I have since switched to a 38:1 mix, with a different Brand oil. I think running at 50:1 was too dry, thus causing ring wear and cylinder wall scoring.
@@OldSoulMillennial I honestly don't think that the ring was the problem .Piston rings are made of super hard steel or cast iron and then chrome-plated which makes them much, much harder than the cylinder wall. Also, adding more oil to the mix will create even more deposits, reduce power and increase heat which is not good for the saw. If the mix was too lean, that would be apparent since the plug's electrode would be gray or grayish instead of chocolate or coffee brown. In any case, I don't understand where all that carbon came from since you ran the saw correctly. Very strange situation.
@@OldSoulMillennial I've been running Amsoil at 80:1 for 6 years with hundreds of hours across three Stihl saws. Not a single problem with wear. I would bet your carb is adjusted too lean at high, causing it to overheat thus causing pre-mature wear. Adding more oil to the mix is a band-aid but I don't think it's the source of your problem.
Rebuild Kit Used: amzn.to/3LSTkkF
Piston Installation Tool: amzn.to/3WSbWYr
I couldn’t have done it without you man thanks a ton
Hey thanks very much. I have a 261 and appreciate all the work and effort in filming it for us. Cheers!
Great saw when it's running properly. I switched to 38-1 Mix, no smoke, more lubrication. Happy Saw
Excellent video. It's going to the library for my MS261. Good video and audio.
Great vid Sir through out, machining building etc...........................definately no commercial BS here !.................subscribed and massive like you gotta be one of the best on the you tube platform, thankyou for your time
Fella i watch named richard flagg did some testing on 2 stroke oil and stihl ultra hp failed miserably. The way he explained it,it was burnin off and not enough was staying behind to lubricate. Ive used it for a few years without any failures in my 3 saws,string trimmer or leaf blower,but im now switching to lucas synthetic land and sea. Looks like an easy saw to rebuild,so at least thats good. Hope it holds up for you
good job.
Compliments to the cameraman!
Great Rebuild Video. I’must subscribed
I'm sure you know by now but there are 2 heads, old and new. My 261 took the new with no need to cut the fins.
I want to ask what are the different parts between stihl ms 261 non-mtronic and stihl ms 261 cm.
Excellent video
AMSOIL is the best oil in my opinion... I am 14 and have a 261 C-M and many other saws and machines. That's what they all run.
@@OliverofAllTrades What oil-gas ratio do you run? I’ve been using 50-1, but I think I’m going to switch to 45-1.
@@OldSoulMillennial 50:1 is all you need for stock saws.
I have read that the you can remove some of the plastic ribbing on the underside of the shroud to make the flat fin cylinder fit under a slant find shroud. Did you explore this option? Do you think it would work? I’m looking to get a slant fin that was straight gassed and rebuild it and was wondering. Great video. Well done camera work.
Thanks
@@dibiase9502 In my case, I had to heavily machine the cooling fins, and grind some of the case ribs. Takes about 2 hours. If you have more time than money, do what I did. I think I explain it in the video reasonable well.
The reason the cilynder doesn't fit properly is because Stihl came up with gen 2 cilynder called slant fit wich is supposed to give a couple more HP and less cooling fins in aprox. 2016-17 . The gen 2 is almost available only from Sthil and was in there saws at the time of change giving a bit of weight lost and lower profile cost lots more $$ I have the gen 1 bought in 2014 with the straight cilynder. Very nice video!!
@@123456773934 So gen 2 has more power and less cooling fins? Sounds like gen 1 was manufactured too well. Had to ensure something would fail!
Ran the saw hard today, and performed very well. Switched to 42-1, no smoke so I’m going to stick with that ratio.
If I ever have to rebuild again, are you aware of any aftermarket gen 2 heads?
My uncle bought 4 brand new stihl 261c mtronics and his laborers blew em all up using the 50.1 ratio. Im going to go through all of them and see if i can salvage em.
@@FastandFoody Definitely worth rebuilding if you have the time. My cheap aftermarket piston and head are holding up very well. Now running 40-1. Still runs very clean.
Why use the decompression button its only 50cc
Why wear a seatbelt, its just a car
@@OldSoulMillennial it probably caused your problem
@@hidhshsj123 Please explain your logic. Are you suggesting it was just a bad decompression valve? I didn’t look for leakage there. I think I would have noticed air bleeding out when doing the compression test.
I use the decompression valve to reduce shoulder strain.
The decompression button saves on many things. Reduces pull starter wear/pull string wear, reduces starting strain. I have a Stihl 261 and I use it. Nothing wrong with using the decompression valve. The decompression valve is awesome.
@@videocardzrule354 Agreed, I don’t know what this Karen commenting above is smoking.
Only use the best 2 stroke oil. It is expensive but rebild your chainsaw is more expensive.
@@stefanlageambecker6077 The rebuild kit I used was 45 bucks.
Stop using Stihl oil. Stuff really does suck. Really sucks your saw gave out in just two years. Great video learned a lot thank you
soooo many people document this. what many are finding is Honda hp2, belray hr1 and motul 800 seem to be best performers. 50 to 1 -- some like 40 to 1.
By the color of conecting rod, saw shown that , its been overheated from unproper usage. Used that same saw for 6 years right now, over 300 tanks gas used. Still runing like it should, 0 engine rebuids so far. Dont know what youre guys fucking around whit this stuff.😂❤💯
bad choice of cylinder kit! way too much cooling fin area removed. you should have bought a meteor kit. 1/2 the $ of oem kit. i did not have to do anything to the fins on the one i used for my 362. not sure on the 261, i used a hyway kit on that one. i had to remove some of the ribs on inside of cover and a small area of cooling fins. both saws i bought off ebay with blown top ends. i run synthetic at 40:1. used to run 50:1. too dicey
@@davidgoliath982 Even after removing the fins as shown in the video, there is still around 20% more cooling fin surface area on the aftermarket head than on the OEM head. Definitely going to switch to 45-1 or 40-1.
@@OldSoulMillennial ya but most was removed from exhaust side. the oem cyl. is designed in a specific way to be efficient with less material to reduce weight and cost
@@davidgoliath982 Well the OEM design failed me after 2 years. I’ll take my chances with this 42 dollar kit.
@@OldSoulMillennial the oem failure was not likely due to the design or the quality. it is almost always operator error. the oil may not be adequate and or the jetting was set too lean or a possible small air leak. also it is not likely that the porting in that budget cyl. replicates the oem porting that well. that has been my experience. i mean it might but........ chances are it will not have all the power it should which may not matter much depending on the type of use
@@davidgoliath982 My argument is that the failure was absolutely due to design and quality issues. I bought a professional grade saw with the expectation that it should last over a decade without needing a rebuild. I used stihl brand recommended synthetic oil. I did not adjust any carb settings until the rebuild. How can you claim operator error when I’ve followed all of stihls reccomendations. Hell, I even let the saw warm up a minute at idle prior to pushing it.
I’ve always been a stihl guy, but I don’t see any excuse here.
This is an excellent example that illustrates why these saws should be run at 50:1 ratio and not a smidge richer. There is so much carbon accumulated inside that after only 2 years it destroyed the engine. And if this saw was run using the 50:1 mix, it wasn't run long, frequently or hot enough to burn off all those nasty deposits. They eventually turned to carbon, flaked off and sanded down the cylinder causing the loss of compression.
@@Steelologist Interesting theory. I have different thoughts. I only used stihl full synthetic mix oil at the pre measured 50:1 ratio. I beat the balls off this saw. It’s not a one cut and done saw, when I start this saw, I expect to be cutting hardwood logs into 16” rounds. Carbon build up unavoidable. I strongly believe 1) Stihls mix oil is crap. 2) 50:1 is too lean. Many have commented that 50:1 is just for the engines to meet epa emissions. I have since switched to a 38:1 mix, with a different Brand oil. I think running at 50:1 was too dry, thus causing ring wear and cylinder wall scoring.
@@OldSoulMillennial I honestly don't think that the ring was the problem .Piston rings are made of super hard steel or cast iron and then chrome-plated which makes them much, much harder than the cylinder wall. Also, adding more oil to the mix will create even more deposits, reduce power and increase heat which is not good for the saw. If the mix was too lean, that would be apparent since the plug's electrode would be gray or grayish instead of chocolate or coffee brown. In any case, I don't understand where all that carbon came from since you ran the saw correctly. Very strange situation.
@@OldSoulMillennial I've been running Amsoil at 80:1 for 6 years with hundreds of hours across three Stihl saws. Not a single problem with wear. I would bet your carb is adjusted too lean at high, causing it to overheat thus causing pre-mature wear. Adding more oil to the mix is a band-aid but I don't think it's the source of your problem.