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HELP! Echo CS-355T Flywheel Key Filing for Timing Advancement

JRHAWK9

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Hi, I just bought my first Echo; a new 355T. Will probably be replacing my Husky T435. I have an EPS pipe on the way for it and I already opened up the intake and removed the limiters. My question is, those who have advanced the ignition timing, how much did you file off the flywheel key? I took 0.02" off of it and it ran like complete crap. I could tell as soon as it started it was too advanced. I went back to roughly where it was stock and left it be....for now. I may buy some additional keys for it and file them differently to try. If I do that I'll probably try taking 0.01" off of it next. What have you guys had good luck with?

Background info:
The width of the key started out at 0.117". I filed it down till it was 0.097". When I installed the flywheel I rotated it CCW up against the key and then tightened it, making sure the flywheel did not rotate. This proved to be too much, as when I put it back to the stock location, everything was fine again.

thanks!
 

singinwoodwackr

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Most newer Echos are already advanced so going further can be a crap-shoot. I recently did 2 of the 355s and went by the distance moved at the flywheel edge, 1/8”, approx, rather than trying to eyeball thousandths. I use a very fine, tiny file and do a few strokes at a time. Both saws run great.
 

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Hi, I just bought my first Echo; a new 355T. Will probably be replacing my Husky T435. I have an EPS pipe on the way for it and I already opened up the intake and removed the limiters. My question is, those who have advanced the ignition timing, how much did you file off the flywheel key? I took 0.02" off of it and it ran like complete crap. I could tell as soon as it started it was too advanced. I went back to roughly where it was stock and left it be....for now. I may buy some additional keys for it and file them differently to try. If I do that I'll probably try taking 0.01" off of it next. What have you guys had good luck with?

Background info:
The width of the key started out at 0.117". I filed it down till it was 0.097". When I installed the flywheel I rotated it CCW up against the key and then tightened it, making sure the flywheel did not rotate. This proved to be too much, as when I put it back to the stock location, everything was fine again.

thanks!
Make sure this saw has the newer style mesh air filter. That is a huge performance gain vs the old woven filter.
 

JRHAWK9

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thanks guys!

1/8”, approx,

wow! Now that isn't a whole lot!

I have a couple keys on order. I'll probably just stick the stock one back in and call it a day.

Make sure this saw has the newer style mesh air filter. That is a huge performance gain vs the old woven filter.

yep, it does. The cover doesn't have that goofy plastic retainer either that the old ones had.
 

singinwoodwackr

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thanks guys!



wow! Now that isn't a whole lot!

I have a couple keys on order. I'll probably just stick the stock one back in and call it a day.



yep, it does. The cover doesn't have that goofy plastic retainer either that the old ones had.
and...when you replace the old with that new one you have to remove the retainer...cuz it won't fit :p
 

JRHAWK9

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OK, next question. What the heck is this for? It was in the bag with the scrench and T27 wrench. The hole looks to have some markings resembling threads, like it's supposed to be screwed into something.


1769345535292.png

1769345581670.png
 

EFSM

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There is supposed to be a different sized palm rest for the top handle in the bag, but that’s not it.
 

JRHAWK9

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Now that I look at it more. It may be a "plug" in case one doesn't want to use either one of those palm rests.
 

JRHAWK9

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Now that I look at it more. It may be a "plug" in case one doesn't want to use either one of those palm rests.

I just looked. That's exactly what it's for. I removed the palm rest and that little piece fills the hole and uses the same screw to hold it in place.

Mystery solved. LOL
 

EFSM

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Hi, I just bought my first Echo; a new 355T. Will probably be replacing my Husky T435. I have an EPS pipe on the way for it and I already opened up the intake and removed the limiters. My question is, those who have advanced the ignition timing, how much did you file off the flywheel key? I took 0.02" off of it and it ran like complete crap. I could tell as soon as it started it was too advanced. I went back to roughly where it was stock and left it be....for now. I may buy some additional keys for it and file them differently to try. If I do that I'll probably try taking 0.01" off of it next. What have you guys had good luck with?

Background info:
The width of the key started out at 0.117". I filed it down till it was 0.097". When I installed the flywheel I rotated it CCW up against the key and then tightened it, making sure the flywheel did not rotate. This proved to be too much, as when I put it back to the stock location, everything was fine again.

thanks!
What do you mean by “opening up the intake”? Enlarging the holes in the cover?
 

JRHAWK9

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What do you mean by “opening up the intake”? Enlarging the holes in the cover?

Yep and also removing some of the material in that "splash guard" that restricts air flow. I was going to remove it all together, but I think I know why it's there, so I just took out some of the ridges to make it flow better. Whether it really needs it done, I don't know, but it looked like a potential restriction to me. Then you look at the size of the throat in the carb and wonder. Man, is that a small throat in that carb. LOL

I removed the ridges in these areas.


1769353085856.png

Stock they are just open in this area, IIRC:

1769353204183.png
 
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