Took it to the mechanic as I’m friendly with them, after a bribe of coffee he took a look. Thinks the low jet is blocked. Told me to bring it back in and he’ll file it out
Ms 260 Pro, How Does It Sound?
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Thanks mate I appreciate it. I’m surprised to hear you think the H is lean in that second video I posted, just a few posts above yours. It’s 4 stroking at 10,000 rpm. I took it to the mechanic and he had the same results. He thinks the low jet is blocked? Told me to bring the carb in and he will file it and re tune.
Is it an old carb? May just need to be cleaned out with some break parts cleaner. It didn't sound horrible just lacked that snap it should have. Not sure what he's going to file.
Tom you had it pretty close the first time.
What it sounds like is one of progressive off idle drillings is blocked.
pure idle is/ was ok in the first vid, but when it moves off idle to the main jet, there are a few more drillings where fuel comes out, my thoughts are that they are the ones blocked, thus the bog off idle, but good idle.
Info on this is in the walbro manual I sent you, when you have the carb off the saw, you will see the idle jet drilling in the wall of the carb venturi, and a bit further up from that is the progressive port and so on, fine copper wire from some unstranded/ unwound speaker/ electrical wire that is fine, should see you move the gunk out of there, and remove the idle mixture screw, shoot a bit of carb cleaner thru, then a gentle shot of air, you will then see if that progressive port is blocked or not.
edited to add, the second vid, the saw is very rich on the high side, been a while since ive heard one like that
What it sounds like is one of progressive off idle drillings is blocked.
pure idle is/ was ok in the first vid, but when it moves off idle to the main jet, there are a few more drillings where fuel comes out, my thoughts are that they are the ones blocked, thus the bog off idle, but good idle.
Info on this is in the walbro manual I sent you, when you have the carb off the saw, you will see the idle jet drilling in the wall of the carb venturi, and a bit further up from that is the progressive port and so on, fine copper wire from some unstranded/ unwound speaker/ electrical wire that is fine, should see you move the gunk out of there, and remove the idle mixture screw, shoot a bit of carb cleaner thru, then a gentle shot of air, you will then see if that progressive port is blocked or not.
edited to add, the second vid, the saw is very rich on the high side, been a while since ive heard one like that
Have you got 5 mins for a call mate?Tom you had it pretty close the first time.
What it sounds like is one of progressive off idle drillings is blocked.
pure idle is/ was ok in the first vid, but when it moves off idle to the main jet, there are a few more drillings where fuel comes out, my thoughts are that they are the ones blocked, thus the bog off idle, but good idle.
Info on this is in the walbro manual I sent you, when you have the carb off the saw, you will see the idle jet drilling in the wall of the carb venturi, and a bit further up from that is the progressive port and so on, fine copper wire from some unstranded/ unwound speaker/ electrical wire that is fine, should see you move the gunk out of there, and remove the idle mixture screw, shoot a bit of carb cleaner thru, then a gentle shot of air, you will then see if that progressive port is blocked or not.
edited to add, the second vid, the saw is very rich on the high side, been a while since ive heard one like that
Yeah it has had two deep, through cleans even removing Welch plugs spraying and soaking in carb cleaner etc. new needle, gaskits and diaphragms
Those tachs are spot on mate, if you have it set up correctly on the right setting for 2 stroke, your fine.It could be wrong I’m not sure how accurate they are. It’s a Japanese tech that’s all I know ha. I’ll go out one more time and see
yeah mate, call anytime before 2100 and after 0800, if were home, we will pick up.
yeah call now, just child wrangling showers and sorting out bed time
Ax-man
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I'll comment for what it is worth. Overall you got it tuned good . Your just a little lean on both the L and H in first vid. I wouldn't feather that saw to get it to run at WOT. If you have to feather it your lean on the L. Drives me nuts to hear that feathering.
The tach is nice but try running the saw in some of that down under hardwood preferably in a bury the bar type cut. This is the best test of how well you got the saw dialed in. If the saw is tuned right it will sound like it is changing gears with no slowing down in mid range of the cut . If it falls off in the middle of the cut your lean on the H or possible the L . After completing the cut the saw should return to a consistent stable idle and stay idling . Hit the trigger again and make another cut and repeat as needed till your satisfied. The saw should accelerate cleanly with no hesitation and chew through the wood with no slow down provided the chain is sharp.
You may have to fiddle with the screws a little but this is the best way to get a saw dialed in.
The tach is nice but try running the saw in some of that down under hardwood preferably in a bury the bar type cut. This is the best test of how well you got the saw dialed in. If the saw is tuned right it will sound like it is changing gears with no slowing down in mid range of the cut . If it falls off in the middle of the cut your lean on the H or possible the L . After completing the cut the saw should return to a consistent stable idle and stay idling . Hit the trigger again and make another cut and repeat as needed till your satisfied. The saw should accelerate cleanly with no hesitation and chew through the wood with no slow down provided the chain is sharp.
You may have to fiddle with the screws a little but this is the best way to get a saw dialed in.
Thanks mate!! Sounds like everyone agrees the L and H are lean in first video. A few things have transpired since
Long and short of it. Low screw oring had to be reused as the kit I brought had the wrong size (another f-up on the manuals behalf!), didn’t think much of it until now, it could be leaking air at the L screw leaning things out slightly. Because I reused the oring, I gave it a little silicone oil to bring some spring back into it, this seems to have gotten hot and seeped down the needle and was black and oily. Clearly not good. I’m a total idiot but I’m new here so have much to learn. Got another oring on order and will clean everything out. The oil blocking the jet hole, tiny tiny bits of metal from the jet screws. plus the dodgy oring could very well all contribute to the lean L screw needing to be twisted out so far (in these videos the l was 1 and 3/4 out already and still lean!). This is no longer fun
You're the guy that wanted to bring back saws from the dead. Did you think it would be without any problems? MikeThis is no longer fun
Yes you’re absolutely right, I can’t do anything but agree with you when you put it like that.
It’s a perfect example of the initial stages of competency.
There is so much I don’t know, that I don’t know what I don’t know.
However I tell myself that every setback is a setup for a comeback and the reward i’ll feel when I achieve success will be greater because of it. I guess it helps! Anyway, I digress.
You are lucky Tom. When I started with a pile of Mcculloch parts and saws (left in the rain no less), there was no one but me to figure it out. No running to the internet every time I was stuck. I learned the hard way. Mike
Makes things much easier now doesn't it. It's also why I have my doubts about what the coming generations will be. Never figuring things out on your own, changes how the brain works, or doesn't. That's just the way it's going to be from here on out.
lol yeah, everything is so much easier now. Cant figure it out? Ask some old timers on the internet (in no way intended as an insult to Tom, I have done this plenty times myself)
(in no way intended as an insult to Tom, I have done this plenty times myself)
Not my intention either, just making a general observation.lol yeah, everything is so much easier now. Cant figure it out? Ask some old timers on the internet
The process of learning is much sped up with a willing student and willing teacher, no matter what generation.
trying to learn from some older chaps, they just didnt want to share what they knew, "took me years to lean this, so you have to spend years learning as well"
stuff that
happy to learn all I can, but there is a point where you need to be watching with eyes and ears open and mouth shut
Other times, is good to ask questions, and the only stupid question is the one you dont ask.
Usual common sense application, general warning etc applies here.
trying to learn from some older chaps, they just didnt want to share what they knew, "took me years to lean this, so you have to spend years learning as well"
stuff that
happy to learn all I can, but there is a point where you need to be watching with eyes and ears open and mouth shut
Other times, is good to ask questions, and the only stupid question is the one you dont ask.
Usual common sense application, general warning etc applies here.
I haven't ventured into pipe saw territory yet. But I just did put together a 266 that is going to need race gas at minimum... Lol
Lots of good info hear.
Usually if a saw wont run upon assembly at base line settings something is out of wack mechanically, like carb itself, impulse line, fuel line, seals
A new saw will run crisp get up and go I've not experienced the saw loosening up and revving higher that some describe here. But I also dont use a tack and never will.
When cutting all day I'll have a tuning screwdriver in my pocket. Make a tweak here or there as needed. I like to hear it burble alittle as it lifted out of the cut.
Hanging rpms coming down to a idle usually means lean.
It will take time and experience to get good at tuning. The tunning process will take much longer with a saw that's got leaks. Itl never be tuned and want constant adjustment at no gain. Can be a frustrating process.
Good luck and have fun with it.
Usually if a saw wont run upon assembly at base line settings something is out of wack mechanically, like carb itself, impulse line, fuel line, seals
A new saw will run crisp get up and go I've not experienced the saw loosening up and revving higher that some describe here. But I also dont use a tack and never will.
When cutting all day I'll have a tuning screwdriver in my pocket. Make a tweak here or there as needed. I like to hear it burble alittle as it lifted out of the cut.
Hanging rpms coming down to a idle usually means lean.
It will take time and experience to get good at tuning. The tunning process will take much longer with a saw that's got leaks. Itl never be tuned and want constant adjustment at no gain. Can be a frustrating process.
Good luck and have fun with it.
Thanks so much for your advice Evan
I agree there is some great advice and lots for me to learn. Yesterday it was a good reminder (when I was feeling very frustrated with myself) when someone commented, “what did you expect to happen when you try and revive a dead saw” which reminded me that mistakes and hiccups are a part of the process and you won’t get perfect results your first time around! Warmest regards mate 
