Stihl MS 661 having the bog blues
- Thread starter funky sawman
- Start date
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As far as the 362cm goes I also had the problem of not being able to use the decom valve. as others have stated the saw wont start with the use of the decom. I believe that if the saw has a option to use, then it better darn well work.... Sometimes while in a tree if the saw dies, a decom is nice to get it restarted. But with 135 pounds of compression hot how could the thing start with the compression bleed of the decom. Im willing to assume that the 362 I got as a loaner has a defective piston and or cylinder.
well that what its supposed to sound like. the 661 is like: waaaaaaaaaaaaaaaaaaaaaaaaaaaa ......wap wap waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa wap boooooooooooooog waaaaaaaaaaaaaaaaaaaaaaaaaa
Deets066
Firewood hack
So.... Should I tune my saws to have a bog in them, because that's how they are designed to run?
****, I've been adjusting my carbs wrong all this time.
Excellent, that is what I will ask the stihl rep and tech LOLSo.... Should I tune my saws to have a bog in them, because that's how they are designed to run?
****, I've been adjusting my carbs wrong all this time.
The old fart that loaned me the 2100cd always told me a saying about new saws, I have NEVER listened cause I a young punk LOL. He said "give that saws ten years on the market then I will buy one, cause then the test of time will say its a good saw" . He hated the 371xp when they came out in 1996 but in 2005 or 06 he bought a new 372xp and loves it, and the fact is, those years of 372's were the best, they had better crank forgings and better clutch's and so on. So maybe I should take a hint......
Chris-PA
Where the Wild Things Are
It is a carb with the ability to adjust the mixture under some limited circumstances. Primarily this is limited by the lack of much of any sensors other than rpm, so they periodically lean out the mixture slightly and watch what happens to the rpm. It's pretty much how we would set the mixture.
This scheme can't operate under conditions where the rpm is changing for other reasons, and so much of the time it is just an old fashioned carb running without feedback control. When you let off the throttle it's running open loop without feedback control - if it won't drop rpm that says it is lean under that condition. Under load the system fixed up the mixture as it was designed to, but open loop it reverts to lean. When you open the throttle again is is also not in feedback control and it's lean again and bogs. The question is why is it lean when not under feedback control?
This scheme can't operate under conditions where the rpm is changing for other reasons, and so much of the time it is just an old fashioned carb running without feedback control. When you let off the throttle it's running open loop without feedback control - if it won't drop rpm that says it is lean under that condition. Under load the system fixed up the mixture as it was designed to, but open loop it reverts to lean. When you open the throttle again is is also not in feedback control and it's lean again and bogs. The question is why is it lean when not under feedback control?
Deets066
Firewood hack
Locust Cutter
Sawing for Sanity
Likely because it was designed to run very lean when not under feedback control as a default setting in order to modify idle/low-rpm emissions. The techs probably are figuring figuring that saws are run either W.O.T. or idle so to combat that they simply made a lean default not counting on people blipping the throttle to maintain rpm (and oil especially with "E" oilers). The Tech's statement about that being the factory setting is likely correct, although I bet something is still amiss with your specifically. I would almost wonder about a small crankcase leak or a possible fuel restriction.
Has anyone noticed that the 661 carbs have a idle throttle plate adjustment??. I wonder if the throttle flap position has anything to do with the problem?
gomoto69
ArboristSite Operative
I understand exactly what the op is saying about getting a rythym going while limbing, and keeping rpm up with the wap wap's between the waaaaa's, as that's exactly how i did it when i was a bucker. For a rep to tell you that's not how a saw is designed to operate hasn't spent much time on a log landing. Maybe stihl needs to have another position on your control lever for limbing, dissableing the feedback metering system to allow the carb to work as a standard carb, sort of a default with a proper slightly rich setting, then flip it back to run when falling or bucking. I can feel your pain of how frustrating a bog would be in that situation, especially when throttle response is supposed to be a selling feature of modern mtronic type saws
Big_Wood
westcoast dweller
bumping up your post count tonight i see funky LOL to be honest, even if i was a homeowner stihl would be doing a little more for me or i'd be getting my money back. plain and simple. they sell **** they're gonna take some ****. the stihl rep here is a cool dude and my buddy owns the stihl dealer. i'm sure it wouldn't even be a question as to what they would do. make the customer happy now and deal with the money lost between the dealer and manufacturer later. maufacturer should have to soak that one up.
Funky, sure sorry to hear about your troubles and that stihl keeps giving you the run around!
You might try checking with STIHLTHEDEERE, he prides himself on being a GOOD Stihl dealer. Im sure he can help you out one way or another.
You might try checking with STIHLTHEDEERE, he prides himself on being a GOOD Stihl dealer. Im sure he can help you out one way or another.
is the 461 bogless??? If so I might just have to bite the bullet and trade the 661 in on one
I'd make them send me a new MS661.
well from what the rep was saying and the tech, all 661's are boggers when used under certain conditions
the GOAT
Chainsaw truther
No thank you, had a few new 390's and not impressed, stock ones anyhow. a ported one would be nice but no money to have it ported
Maybe stihl is gonna let the standard carby 661 come to the US market , that would be kinda awesome.
Blame it on auto-tune.
Blame it on auto-tune.
