Echo CS-400 Chainsaw Muffler Mods

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squeals at idle goes away when the clutch locks up all I did was drill the cat out with a taper bit and cleaned all the shavings out and bolted back on and richened it up.

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Do you let the saw sit outside in the rain? Now I can't remember but I believe there is bearing that the clutch rides on. Take some high temp grease and put a little on it. I had a older Poulan that made a squeal.


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I pulled the muffler off my cs4400 this evening.. all ready to rip the guts out.. to my surprise there was nothing in there.. from what I could tell it was pretty much a hollow can with a side pipe going into the screen and deflector, I took the screen and deflector off but didnt notice any difference.. Is there any way to mod this muffler? thanks!

No there's not put it back together and cut wood.


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400vs 2600?

so i just got a poulan 2600 in nice light lil saw needs work but cylinder is great and it has spark.... i was curious to know if anyone had cut with both these saws with muffler mods???... on the 2600 will only have very lil mods to make loose the screen and open it up drill the baffle holes.... these saws are pretty close cc wise size and weight... the one i got is real clean im thinking of keepin her but ive been wanting an echo-400 with all i have read on this thread anyone have both???? how do they satck up if you cut with each one same bar and chain?
 
cs400

the cs 400 will be the easyest saw to start.the muff on the 2600 is very restrictive and should respond well to moding. the muff on the 295 pro is so restrictive you wonder how it runs,and the 2600 is close to the same.Steve
 
huh?

the cs 400 will be the easyest saw to start.the muff on the 2600 is very restrictive and should respond well to moding. the muff on the 295 pro is so restrictive you wonder how it runs,and the 2600 is close to the same.Steve

i think your wrong my brother! the 2600 was easy take apart muffler remove screen drill it put it back together and done in20 minutes or so... then was the tuning in wood that took me a lil bit to get the plug that nice brown .. but i was sorta playing... my 295 i agree its very restricted i may buy an older 2900 muff .... thats like the 2600 was it was cake.....i have to say my lil 2600 cut dam good with new bar and chain all tuned up in 10 inch pine.....better then my 295 i need to muffler mod it and drop down a bar size for sure!!!! i wish i was close to someone with and echo id like to race one they say those lil echos cant be beat i think i will get me a good used one and find out myself... i paid about 40 bucks for the 2600 perfect P/c and carb!!!
 
cs-400 muffler mod

I just got my cs-400 yesterday.
I think I will break it in first before I mod it?
Any thoughts on this?

Will be running 87 mixed at 28/1...klots super techni plate...same as every two stroke I own.
 
I just got my cs-400 yesterday.
I think I will break it in first before I mod it?
Any thoughts on this?

Will be running 87 mixed at 28/1...klots super techni plate...same as every two stroke I own.

I would suggest 4-5 tanks before you mod it. You won't believe the difference it makes. And just my $0.02, but 28:1 is heavy on the oil. 40 or 50:1 is fine.
 
tuned

Pull the caps and tune before you run it, a lot come set burn up lean. 40 to 1 is good. Steve

Thanks!
I cut some small 5" logs into shorter logs and mostly gave it short blip:chainsaw:s before the cuts...then checked the plug. It was super lean.
Pulled the caps, broke one and pulled the metal plate off with the cap. Managed to save one.
I wanted to save both and shave the tabs off and put them back on...oh well.
The fuel air mixture was waaaay to lean.
 
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I just ordered a Echo CS-400 and expecting it to be lean also, Iam not sure where to start on adjusting the carb so that its spot on. Can someone point me in the right direction? Thank You
 
Can you tell if a saw is running lean or rich? If you can than turn the high side out maybe 1 turn from the factory setting than make test cuts and slowly turn it in until the saw quits four stroking when cutting wood. I set mine plenty rich (four stroked through most of a cut) for the first 4 or 5 tankfuls. I haven't touched the low side it was set very close from the factory.
 
Did the muffler on my CS346 today

After reading this thread and looking at the pictures posted, i decided to go to work on my Echo CS346.

First thing I noticed was that the muffler is different. I modified the exhaust outlet to match the size of the exhaust port on the engine. There was no need to modify the deflector because it was already wide open. Once I opened up the exhaust outlet, I could see a horizontal baffle between the intake and outlet sides of the muffler. I thought of trying to bend it a bit to open the space at the bottom but it wouldn't budge. Accordingly, I got out the Dremmel and bored a 3/8" hole in the centre of the baffle that lines up directly center with the exhaust outlet. I put blue locktite on the screws, buttoned everything back up and took it for a few test cuts.

Seat-of-the-pants dyno indicates an immediate improvement in how quickly the engine revs up and seems to sustain more power while under substantial load. In the past, the saw would cut fairly well on eight or ten inch diameter sticks, but on big wood, the saw would seem to bite off more than it could chew and power would sag. Now it seems considerably more eager to go through larger logs. I think the carb is set a bit rich. It popcorns at wide open throttle and I figure I can lean it out a tad to squeeze a bit more power out of it. I'm pretty familiar with tuning two cycle carbs (I own a number of vintage Yamaha 2 cycle motorcycles and tons of two stroke OPE) so I know the importance of not setting the carb too lean.

Overall, I'm pretty much impressed with this little saw. Since owning it, I hardly use my Jonsereds 630 and 670. I've got to have a lot of big sticks to buck to pull one of those saws out.
 
Another warantee voided!

Hey folks

Completed these mods over the week and wanted to also thank team fast for this guide.
The CS-400 is a fine saw straight from the factory so consider carefully your options for
service in the future before heading down the "crossroads".

I burned around a gallon of fuel prior to performing the modifications.

The result is a easier breathing saw that has H/L adjustability.

Runs better for certain and allowed me to fine tune her perfectly.

A few notes from my experience:

The catylitic converter is exactly that so expect a platinum and ceramic
honeycomb requiring brute force to remove. A standard screwdriver and hammer!
or drill it out. I used a small drum sander to clean up the inner sleeve of material
remnants once the guts were removed.

The saw is no louder at all. If anything it's less frenetic!

Please note team fast mentions the need for some level of back pressure for scavenge!

Not much on removing the H/L limit sleeves....

I followed the idea of using a long drywall screw. Chopped off the very tip and slowly
screwed into the sleeves which pulled out the metal retaining ring and limiters as a whole
assembly. Concerned enough to retain their use to keep the screws from moving during
use I nipped off the "wings" and reinstalled the sleeves and retainer. ROCKS!

Tuned her up this evening great link to the video with setting the high and 4/stroking
in the load of a cut. I kept a little burble just to break her in over a few more tanks
but she cuts really well.

Just another big thank-you to everyone who posted and offered their solutions.

I had a spare part lodged under my carb - a wire grommet !
guess it was lost during assembly. If the builder hits the sweet spot on the
H/L the limiters might be workable I'm at a full turn out on the H almost there....

My grouse with this saw is the oiler is messy and took awhile to get it right
but it runs thru the bar oil - sure miss the thumb pump for the bar oil.

The top handle is too narrow at the safety for me needs just a little bending!

Safety clutch is hi impact plastic but seems cheap and fragile but the clutch
Really works very well.

You sure can't beat the ease of chain changes with the adjuster the fiddley part
but just the bar bolts and swap. Very sweet....

So far starts easy and is an easy puller.

Get a descent Oregon chain and the foliage trembles!

Thanks a ton folks

Most of all be CAREFUL folks use yer head and think safey!
 
Service Manual fo CS-400?

Any chance one of you Echo Enthusiasts has a Service Manual for this saw that they could share? I tried the "Beg for Manuals" thread but got no bites.

I recently picked up a CS-400 and like to have the SM for each saw, especially for reference a few years down the line when i am more likely to need it. Figured that one of you guys might have snagged a copy along the way.

Thanks a bunch.

Philbert
 
muffler mod comple and tuned = bad a$$

when i first got my cs 400 out the box it would take 3 minutes to warm up and finally get running, it would bog down through cuts and was just a plain pathetic saw, my 1995 beat to crap craftsman would out preform the new echo????? i found this troubling and came online to find answers i then found this site and did the mods and tuning and dang you guuys arent joking its a whole new animal, thank you guys for the helpful thread and rejuvenating the epa restricted saw to its youth lol, im very happy how things turned out !!!!!
 
I got mine about 4 years ago and it was a decent runner but felt underpowered. I didn't want to void my warranty so I lived with it.

I finally took the plunge last week and drilled out the cat and pulled the limiter caps. Man, oh man what a difference that makes!

Now I just need to throw decent loop of chain on there instead of that crappy 91VG it came with. Why did I wait so long?
 
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