Too much transfer duration

David Young

Well-Known Member
Jun 17, 2013
293
826
93
How do I know if I have too much transfer duration.

Runs like crazy. If I bury bar noodle and really push it will stall out but it sounds like the saw is flooding out. Also fuel consumption is rather progressive. How do I recover more blowdown? Or is it tfb?
 

Wigglesworth

autotune gives me a pop-up
Jan 9, 2012
1,604
2,753
0
38
West Kentucky
How do I know if I have too much transfer duration.

Runs like crazy. If I bury bar noodle and really push it will stall out but it sounds like the saw is flooding out. Also fuel consumption is rather progressive. How do I recover more blowdown? Or is it tfb?
Gonna need a bit more info. What saw? What timing numbers? Tuned correctly?

Transfers are funny sometimes, at least to me. Sometimes the difference between running, and running like a bastard is just a misshapen corner, or a couple degrees. Too little duration and they act lean, too much duration and they can act lean as well.

It takes fuel in the chamber at exactly the right time to make maximum power...
 
  • Like
Reactions: 2 people

David Young

Well-Known Member
Jun 17, 2013
293
826
93
Gonna need a bit more info. What saw? What timing numbers? Tuned correctly?

Transfers are funny sometimes, at least to me. Sometimes the difference between running, and running like a bastard is just a misshapen corner, or a couple degrees. Too little duration and they act lean, too much duration and they can act lean as well.

It takes fuel in the chamber at exactly the right time to make maximum power...

Ms310
126 duration
ex. 160


runs like a scalded dog until I really push on it.
 
I assume you are talking about a stock saw .Firstly if I recall correctly a 310 is a clamshell designed like a 290 .Also I believe the carb has fixed limiters on it .

What you likely have has not one thing to do with the duration of the transfer cycle but more to do with fuel delivery .If said saw cannot deliver the fuel in a heavy cut it will falter .As designed small saw or no it should be able to hang tough with the bar buried .

Now if you've got into it and fiddled with the port timing all bets are off on what I said .
 

David Young

Well-Known Member
Jun 17, 2013
293
826
93
Consider it fiddled.

I assume you are talking about a stock saw .Firstly if I recall correctly a 310 is a clamshell designed like a 290 .Also I believe the carb has fixed limiters on it .

What you likely have has not one thing to do with the duration of the transfer cycle but more to do with fuel delivery .If said saw cannot deliver the fuel in a heavy cut it will falter .As designed small saw or no it should be able to hang tough with the bar buried .

Now if you've got into it and fiddled with the port timing all bets are off on what I said .


Yeah I messed with it a little. I had the timing advance and ended up backing it off a bit.
http://m.youtube.com/watch?v=ZYB-4UCoR4s.
 
Contrary to popular belief it doesn't always help to jack the ignition timing .A standard Stihl is around 27 degrees advance already .Now I've had success on McCullochs' which are 26 advance but they have a slightly lower compression ratio than most Stihls .

I was talking about altering the port timing like raising the exhaust port .
 

naked arborist

New Member
Jun 23, 2013
1,472
2,127
0
Merica kinda... So. Joisey
Yeah I messed with it a little. I had the timing advance and ended up backing it off a bit.
http://m.youtube.com/watch?v=ZYB-4UCoR4s.
Try this:
Choke the muffler back up just a bit. Finer mesh in the screen should do it or add one back on the larger exhaust port. The 029 has the same problem at 125. You need to put the back pressure on it with the bigger bar buried. Seems like most of those carbs loose the vacuum signal when pushed to their limits. Zama just can't hang with a good old fashion Walboro that low in the R's. Let me know if that works out for you.
 
Thread starter Similar threads Forum Replies Date
T Compression, how much is too much? Woodz Porting & Saw Buildz 21
Jimmy in NC Too much power? Broken rim... Chainsawz 24
Fifelaker How often is too often to pull your jug Chainsawz 20
DefinitiveDave dont look, too good for T1 Chainsawz 10
David Young Flywheel too tight? Chainsawz 9
thomas1 Garden Tractorz And Tim's Other Weird Shit, Too. Hawgz Back 40 1718
DefinitiveDave way too long, no need to read unless you like boring crap, dumb questions and free stuff Chainsawz 30
B Me too, me too!!! New Memberz Area 16
S it was such a good plan too . . . . Chainsawz 4
jrcat Too many choices The Razorback Lounge 3
thomas1 It's not too bad. Chainsawz 1
Homelite410 Too redneck? Chainsawz 17
WoodChuck'r Too wet and rainy..... Hawgz Back 40 21
cowroy Hi men! You too Mrs. J New Memberz Area 22
TK 545's are shipping early too! Chainsawz 71
SKEETER McCLUSKEY Look how much stuff I had to gather just to have Phil come spoon with me, at my house. Alone. Don't The Razorback Lounge 44
stihl sawing Well, so much for cold weather killing bugs. The Razorback Lounge 19
Majorpayne Coffee: What Kind and How Much The Razorback Lounge 59
Nixon Thanks so very much ! The Razorback Lounge 16
K How much wood would a woodchipper chip? Hawgz Back 40 5
Jimmy in NC How much do you keep around? Chainsawz 19
trx250r180 Tapered transfer ports ? Chainsawz 31
H Alum transfer removal attempt #1 Chainsawz 23
Eccentric How to Remove Aluminum Transfer WITHOUT Acid. The thread Randy SHOULD have started here.... Chainsawz 37