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

[JRHAWK9]

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!

 

[Ketchup]

It’s been several years, but if I remember correctly I could not find an advance point that improved performance and put it back to stock. Good gains in the muffler though.

 

[singinwoodwackr]

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.

 

[EFSM]

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]

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]

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

 

[JRHAWK9]

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.

 

[EFSM]

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

 

[JRHAWK9]

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

I do have that too. It's white.

 

[EFSM]

I do have that too. It's white.

Chain catcher?

 

[EFSM]

I don’t see that anywhere on the parts diagram or included tools.

 

[JRHAWK9]

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]

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]

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]

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.




Stock they are just open in this area, IIRC:

 

[EFSM]

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.


View attachment 480790

Stock they are just open in this area, IIRC:

View attachment 480791

That anti-spit plate is more necessary with the old style filter.

 

[JRHAWK9]

What are your guys thoughts on the -EPS PIPE- vs the OEM muffler opened up in terms of performance? The little I know about those pipes, they may gain some in peak HP over a stock, unmodified, muffler but tend to lose in torque. No expansion chamber what-so-ever and where it bolts to the cylinder it immediately gets bottlenecked into 1/2" pipe. Definitely not ideal, IMO. I actually have one being delivered tomorrow, but tonight I took the stock one and modified that.

This is what I did, sorry no photos of mine, as it's already bolted on the saw.

I took a hammer and flattened out this part so that the whole outlet area of the deflector is opened up.:


Then I cut this area open:



This is one I found online of somebody else's saw. I opened mine up a bit further down as shown in my sketch above.


The total area of the two outlets now are a bit more than that of the area of the muffler inlet. I did put the spark screen back in for the time being to see how I like it.

I'm thinking this should perform better than the EPS pipe.....??

 

[DillonBuck]

It’s not a drive key, it’s a timing key. It’s not even needed for function, once timing is set.
Loosen up the flywheel mark something in line with a vane with it stock, then advance it. Make another mark in line with the same vane. Now go back 1/4 or 1/2 the distance between them. Try it.

This is easy, try timing a Husky with the key cast in the flywheel. But spun off.
I took a SWAG. Chisel marked the crank and flywheel. Then kept advancing by eye.
Made a final mark when it was right.
Then brake cleaned it, lightly lapped it with water base lapping compound, and tightened it down with the compound in place.

That’s what small engine racers commonly do.

 

[EFSM]

What are your guys thoughts on the -EPS PIPE- vs the OEM muffler opened up in terms of performance? The little I know about those pipes, they may gain some in peak HP over a stock, unmodified, muffler but tend to lose in torque. No expansion chamber what-so-ever and where it bolts to the cylinder it immediately gets bottlenecked into 1/2" pipe. Definitely not ideal, IMO. I actually have one being delivered tomorrow, but tonight I took the stock one and modified that.

This is what I did, sorry no photos of mine, as it's already bolted on the saw.

I took a hammer and flattened out this part so that the whole outlet area of the deflector is opened up.:
View attachment 480876

Then I cut this area open:
View attachment 480877


This is one I found online of somebody else's saw. I opened mine up a bit further down as shown in my sketch above.
View attachment 480878

The total area of the two outlets now are a bit more than that of the area of the muffler inlet. I did put the spark screen back in for the time being to see how I like it.

I'm thinking this should perform better than the EPS pipe.....??

Try it both ways and report back.

 

[huskihl]

Try retarding the timing a few degrees