Echo CS-400 Chainsaw Muffler Mods

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thanks for sharing that info,,as you can see i run echos and i have found myself it makes a big difference to open them up
 
Guys,
I just removed the muffler from my CS-400 and am about to fire up my dremel. A couple of questions...
1. Does the Cat need to be cut out? When I cut open the hole on the back of the muffler will that free up the cat to just fall out or does it need to be cut?
2. If the cat needs to be cut out whats the best way?
3. How to I remove the carb caps that someone mentioned to tune the saw? Does this mean just adjust the carb settings on the side of the saw (the ones for idle and high rpm?).

Someone please help me... I'm a noob with this chainsaw and I want it to cook:blob2:!

Thanks everyone,
Adam
 
Guys,
I just removed the muffler from my CS-400 and am about to fire up my dremel. A couple of questions...
1. Does the Cat need to be cut out? When I cut open the hole on the back of the muffler will that free up the cat to just fall out or does it need to be cut?
2. If the cat needs to be cut out whats the best way?
3. How to I remove the carb caps that someone mentioned to tune the saw? Does this mean just adjust the carb settings on the side of the saw (the ones for idle and high rpm?).

Someone please help me... I'm a noob with this chainsaw and I want it to cook:blob2:!

Thanks everyone,
Adam
Take a drill and drill out the cat then flip it upside down and make sure all the little particles are out.

Limiter caps are easy, take a dry wall screw or something similar and thread them into the cap, now take some pliers or whatever and pry them out. Once removed you can tune your high speed needle and your low speed needle. I recommend richening it up a bit until about 3 or 4 tanks, then lean it out.
 
the last slide where it says, "40cc Echo now hangs with 55cc saws!"

You haven't run too many 50cc saws have you? Let me just suggest you change that slide.

My little CS400 with that NK chain cut 1 second faster than my open port Husky Rancher 55 (53cc) . Both with sharp chains. My Rancher 55 is by far my slowest 50cc saw, yes it's tuned good with 150# comp. Let me suggest you run a muff modded tuned right CS400 with a NK chain. Steve
 
My little CS400 with that NK chain cut 1 second faster than my open port Husky Rancher 55 (53cc) . Both with sharp chains. My Rancher 55 is by far my slowest 50cc saw, yes it's tuned good with 150# comp. Let me suggest you run a muff modded tuned right CS400 with a NK chain. Steve

Sounds like a need to swap my husky 55 for a cs400.......
 
tuning cs400 after muff mod...someone help me please.

mountainlake and other cs400 aficionados in this thread,

ok.. finally after about 3 weeks of jobs i needed my trusty cs-400 (my only saw) for I decided today when I got home from work to play around with the following thinking that i probably wouldn't be able to finish the mod. i was wrong. I used a dremel tool with a 1 inch regular cut off wheel to open up restrictive small hole before the cat, then i used some wd-40 and a super sh1tty old 1/2" drill bit and a screwdriver and went to town on the catalytic converter. then i polished the 1" chamber that now is open and freed up thanks to removing the cat. i also cut the front out of the muffler where the exhaust holes where and made the hole the same shape as the indentation on the spark arrester screen. then i cut the silver spark arrester plate dome thing off. i basically followed the pictures in this thread to a t. thanks team fast.

this is where i am at now: I need someone to help me tune the H and L needles... should i just follow the manual? or is there some other tuning procedure that I should follow considering that I just majorly opened the saw up on the exhaust side. also... is there any other ways to make this bad boy breathe any better? new carb or air filter element? do they make hi-performance air filters for saws? what kind of chain should i buy and where should i buy it? i know there are a lot of questions but I figure you echo guys can help a brotha out.:chainsawguy::chainsawguy::chainsawguy:

thanks guys!
adam
 
How many tanks have you ran thru it?

Filter is the best in class, get a non safety chain that will help a bunch.
 
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i've run about 10 tanks of gas with the stock muffler. i have only been running 89 octane at the lowest and redmax 2stroke oil out of it. i think i should start running 93 with the muffler mod though.

1 more question for TEAM FAST or anyone that has done his cs-400 mod... in slide number 8 it says that you enlarged the 6 internal baffle holes from .25 to .281". how the hell do i get to those baffle holes? do i need to split the muffler and braze it back together? because if thats the case i can not do that i don't have the brazing stuff needed. is there a way to enlarge the 6 baffle holes without the split? Can i still recognize the gains team fast posted with his flowbench that he did without enlarging the baffle holes? how do i do it?


thanks a million,
adam
 
Teamfast- your slides are great, thanks! :clap:

I did this mod for my cs-370 except I did not enlarge the baffle holes-(did not want to split the canister open). I did the deflector like teamfast and deleted the spark screen. I got the Kat out by taking a pair of bent-nosed needle nose pliers and just pulled the guts out, it's easy. clean up the burrs with a dremel stone. Flush with hot soapy water.

IMO it's not totally needed to enlarge the baffle holes, my cs-370 is super responsive now and the noise level is no more than stock, maybe the idle sounds a bit different. Use copper coat on the muffler gasket as a dressing to stop exhaust leaks at cylinder. A better chain is the biggest help.
 
miles said: IMO it's not totally needed to enlarge the baffle holes, my cs-370 is super responsive now and the noise level is no more than stock, maybe the idle sounds a bit different. Use copper coat on the muffler gasket as a dressing to stop exhaust leaks at cylinder. A better chain is the biggest help.[/QUOTE]

ok thanks, what is copper coat? is it like a loctite kind of paste on stuff? whats the brand name and where can i get it?

thanks,
adam
 
HLC03:

Hey,

it's made by CRC "KW Copper Coat" get the 4 oz. brush top can, not the spray. Shake the can well to mix the product, let it sits for a few minutes to get tacky.
 
thanks for the tip on the copper coat... i'm going to pick some up real soon.

heres my next question though: i just finished painting the muffler with 1200 degree black paint (pics coming soon). how hot do you think that muffler gets? and I really want to know what the best way to tune my saw is. i heard that i need to take a drywall screw to pull the caps off the needles. i have run about 10 tanks of 89octane with redmax 2stroke mix out of the saw since it was purchased new last summer and i put sta-bil fuel stabilizer in there in the winter. I am going to switch to 93 octane today and run nothing but 93 out of the saw from now on. my question is... How do I tune the saw? Do I just tune it the way it says to in the echo manual? can someone help me with a high performance carb tune?

thanks guys,
adam:chainsawguy:
 
I did this same procedure on my CS-400 this week. I did not enlarge the baffle holes either as I did not want to split the case. The cat was a little bit harder to get out than I originally thought but used needle nose pliers, screw driver and a drill with an old large bit to get the cat and material out. I can't believe how restrictive that must have been !

It's raining here but I am going to get it into some wood and tune it asap.
 
thanks for the tip on the copper coat... i'm going to pick some up real soon.

heres my next question though: i just finished painting the muffler with 1200 degree black paint (pics coming soon). how hot do you think that muffler gets? and I really want to know what the best way to tune my saw is. i heard that i need to take a drywall screw to pull the caps off the needles. i have run about 10 tanks of 89octane with redmax 2stroke mix out of the saw since it was purchased new last summer and i put sta-bil fuel stabilizer in there in the winter. I am going to switch to 93 octane today and run nothing but 93 out of the saw from now on. my question is... How do I tune the saw? Do I just tune it the way it says to in the echo manual? can someone help me with a high performance carb tune?

thanks guys,
adam:chainsawguy:

Adam check out this thread on tuning. Brad even posts a good video.
http://arboristsite.com/showthread.php?t=113538
 
Adam check out this thread on tuning. Brad even posts a good video.
http://arboristsite.com/showthread.php?t=113538

hey thanks for the link and rep power comin' your way.

i wanted to let you guys following this thread know that i completed the mod and put the copper coat on both sides of the gasket, put the muffler back on, added some 93 octane fuel and started her up this afternoon. i haven't tuned her yet or run her through any wood but damn, when i rev it the saw wants to raise the bar up. it seems like it really made a huge difference. i will post when i get it tuned and into some wood. btw, i also polished the muffler port pretty good and shinny.

best of luck with your mods,
adam
 
hey thanks for the link and rep power comin' your way.

i wanted to let you guys following this thread know that i completed the mod and put the copper coat on both sides of the gasket, put the muffler back on, added some 93 octane fuel and started her up this afternoon. i haven't tuned her yet or run her through any wood but damn, when i rev it the saw wants to raise the bar up. it seems like it really made a huge difference. i will post when i get it tuned and into some wood. btw, i also polished the muffler port pretty good and shinny.

best of luck with your mods,
adam

I am getting mine together and tuning this weekend. I'll post here on my findings as well.
 
Def. gonna give my 370 a work out tmrw. Hopefully ill get it tuned just right, that safety chain needs to go though!
 

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