I bought a 460 a couple weeks ago pulled the carb limiters and did a muff mod, screwed the high and low all the way in and backed them out 1 1/2 turns. Today i got to put it in some wood it started right up but would not idle without a little throttle got it warm made a cut then opened the low another half and it idles good i opened the high another 3/4 turn. it says on the side panel 3/4 turns for both so is that from screwed all the way in or from the limiters. Does my adjustments seem right, it seems like a lot to me for just a muff mod
Ms460 tuning
- Thread starter Gjt1980
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BRad snelling I think has a good video on how to tune by ear I think. You need to run it rich enough that it four strokes and then when you lean on it in the cut it will two stroke. Most tune that way.
1 1/2 turns out doesn't seem out of line at all as a MM will flow quiet a bit more than the heavily restricted stock hole.
Also have to remember the saw was factory tuned for emmisions as well so it was lean to begin with when you got it.
1 1/2 turns out doesn't seem out of line at all as a MM will flow quiet a bit more than the heavily restricted stock hole.
Also have to remember the saw was factory tuned for emmisions as well so it was lean to begin with when you got it.
cutforfun
Addicted to ArboristSite
Seams like a lot to me. I go one out on both to start and go from there. If i get more than 1 1/2 out i start to question if there is something wrong
Locust Cutter
Sawing for Sanity
I'm not sure about the 3/4 baseline reference, as I don't know if it's for the factory assemblers to give 3/4 of a turn, then install the limiter, or it that measurement is taken within the context of the limiter's range of motion. Either way, the 460 has decent displacement. When I modded the muffler on my old 039 (64cc) i had to give it about a half a turn on the low side and about 1.5-1.75 turns on the high. There are plenty of tuning threads to search on and videos as well. A tach is handy, but as long as its 4-stroking decently full-out unloaded and cleans up to a 2-stroke him in the cut and idles decently, you're doing alright. That 039 was considered by many to be a dog, but after the mod, it was a whole new saw and competent by just about any seasoned firewood hack's definition. Good Luck!
It is a new saw so i don't want to run it wide open with no load on it yet. It idles fine and throttle response is good and is aggressive in the wood. When backed out the high another 3/4 after the first cut it did not seem to change the performance in the cut
Pull the limiters if you can and then start at 1 1/8 turns out on both. Get it warm and then hit it WOT for a couple seconds and if it's burbling some it's good. If not it's still lean. The dealer if you take it in is going to rev it wide open and tach it. There's a good tuning sound clip on madsens website and blsnelling has a good video of tuning a 440 I think.
Locust Cutter
Sawing for Sanity
When it's too rich, it will be sluggish on acceleration and will 4-stroke constantly regardless of load. After that thing's had a few heat cycles, don't be afraid to give'er hell. It's the only way to seat the ring(s?) properly.
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cutforfun
Addicted to ArboristSite
2 turns out is not normal imop, i would think with a muffler mod u should be under 1 1/2 out on the h needle. The saw should clean up when it is under a load in the cut.
cutforfun
Addicted to ArboristSite
Dont want to come across as a smart azz, 1 full turn ,not half turns correct
They are full turns i have been around 2 strokes for a long time. It definatly seems like a lot to me but it cuts great and starts easy. Tomorrow i will tune it without using wood. I was told by someone on as not to do wot out of wood until it has cut some wood
A neighbor brought over a craftsman hand blower and siad it would only run half choked.
I slotted the adjustment screws (not-so tamper proof now) and turned the high side screw out two full turns before the motor started to four stroke. I adjusted to where it would four stroke cold and once warmed up it would two stoke. Blower ran strong after that. I still find it hard to believe it didn't melt down runnign as lean as it was. So after that I can believe it would be two turns out from factory lean settings.
Watch and listen
[video=youtube;5BZkB9QQTJU]http://www.youtube.com/watch?v=5BZkB9QQTJU[/video]
I slotted the adjustment screws (not-so tamper proof now) and turned the high side screw out two full turns before the motor started to four stroke. I adjusted to where it would four stroke cold and once warmed up it would two stoke. Blower ran strong after that. I still find it hard to believe it didn't melt down runnign as lean as it was. So after that I can believe it would be two turns out from factory lean settings.
Watch and listen
[video=youtube;5BZkB9QQTJU]http://www.youtube.com/watch?v=5BZkB9QQTJU[/video]
ConcordGarden
ArboristSite Lurker
I would strongly advise against tuning the high setting on an MS460 by ear... Running WOT over 13,500rpm and you are going to fry that thing in a heart beat..
Tachometer's are a cheap investment for a $1000 saw.
Tachometer's are a cheap investment for a $1000 saw.
well thats BS start rich and lean it out bit by bit untill it is not 4 stroking any more unloaded in the cut will only take 2 seconds to see and rich'en it up tad so it 4 strokes unloaded job done and only ran lean for 2 seconds easy
splitpost
Nothing but 32:1
don't sweat it,blowers never see wood and they tune the same way
That is not true at all.
To the OP...Either your saw is tuned WAY rich, or there's something significantly wrong with it, as in a MAJOR air leak, or a malfunctioning carb.
sefh3
Addicted to ArboristSite
On a new saw or any saw that has not been modded a tach is good. Once the muffler has been modded, the tach will get you close but not exact.
