Echo Cs 400 Mods

[Nicutmafia]

Hey guys I'm new to this site but what better site to get chainsaw wisdom than arboristsite? Hello from Oklahoma.
I just acquired an almost new CS 400 today for $150. This thing looks like it may have been used to cut a few limbs. It's my 1st Echo as I usually buy Stihl saws. I have 2 questions about the Echo. I hear that they are set really lean from the factory and that the mufflers really choke the saw down. I know that there are mods that you can do for the muffler and remove the limiter caps and retune. Can someone please fill a new guy in on these modifications and maybe someone has written something up with pictures on the muffler mod. Thanks and all information will be greatly appreciated.....

 

[RedFir Down]

Congrats on your cs-400 score!
Yes they normally do come lean from the factory.
Here is how I muffler mod them.
I found using a 7/8" whole saw bit get rid of the CAT in a hurry.



Next open up the outlet...



Then open up the deflector...



Do all the grinding with the muffler removed from the saw and make sure to get ALL the filings out before putting the muffler back on (I wash mine out with hot soapy water)

As for the carb limiters... If your not familiar with removing them I suggest you take the carb off first. Then you will see the red caps have 2 tabs. Line them up with the cut outs on the carb body, thread a sheet rock screw a turn or so into the limiter and pull out with some pliers. Trim the tabs off the limiters and push them back on.

This should give you a good start.
Are you familiar with tuning a saw?

 

[Rokon]

The best mod for a cs-400 is to keep the chain sharp. IMO that's one of Echo's best late model home owner saws.

A clean, used cs-400 STOCK on Craigslist worth 100-150. Modded cs-400, less than 100.

 

[jrs_diesel]

I bought one last fall and am impressed how well it cuts in stock form. Mine came with Oregon 91PX on it, and from what I read here, a muffler mod and Oregon 91VXL (non-safety chain) really makes the CS-400 come alive. I have not modded mine yet beyond adjusting the carb more rich than factory settings (want to keep the warranty).

 

[Chris-PA]

I bought one last fall and am impressed how well it cuts in stock form. Mine came with Oregon 91PX on it, and from what I read here, a muffler mod and Oregon 91VXL (non-safety chain) really makes the CS-400 come alive. I have not modded mine yet beyond adjusting the carb more rich than factory settings (want to keep the warranty).

I have a lot of lo pro chain, and I'd put my money on the 91PX for speed. Those ramped drive links don't get in the way at all, and the chamfer chisel cutters on the 91PX are fast if properly sharpened. The biggest problem is the cutters are short so it's a poor value.

 

[Nicutmafia]

Will they remove the limiter caps and tune at the dealer? I have an Echo dealer within 10 miles? Is there a muffler swap that can be done to accomplish the same thing as the muffler mod? Thanks for all the great information by the way.

 

[RedFir Down]

Will they remove the limiter caps and tune at the dealer? I have an Echo dealer within 10 miles? Is there a muffler swap that can be done to accomplish the same thing as the muffler mod? Thanks for all the great information by the way.

No dealers will not remove the limiters caps entirely (they are not "allowed" to... EPA reasons). Im sure they will tune your saw for you though. But if you take it to them after you opened the muffler up im not sure how that will go over... they might turn you away. Most all dealers will only work on 100% stock saws. (I was recently told by one of my dealers that I was going to blow up one of my Autotune saws by opening up the muffler.)

No there is not a non cat cs-400 muffler available.

 

[Nicutmafia]

Congrats on your cs-400 score!
Yes they normally do come lean from the factory.
Here is how I muffler mod them.
I found using a 7/8" whole saw bit get rid of the CAT in a hurry.

View attachment 397847

Next open up the outlet...

View attachment 397848

Then open up the deflector...

View attachment 397849

Do all the grinding with the muffler removed from the saw and make sure to get ALL the filings out before putting the muffler back on (I wash mine out with hot soapy water)

As for the carb limiters... If your not familiar with removing them I suggest you take the carb off first. Then you will see the red caps have 2 tabs. Line them up with the cut outs on the carb body, thread a sheet rock screw a turn or so into the limiter and pull out with some pliers. Trim the tabs off the limiters and push them back on.

This should give you a good start.
Are you familiar with tuning a saw?

RedFir Down, is that the part of the cat that you took out in the 1st photo of your post?

 

[RedFir Down]

RedFir Down, is that the part of the cat that you took out in the 1st photo of your post?

Yes that is whats left of the CAT after my 7/8" bit got done with it.

You can drill, pry and pull the cat out if you dont have a 7/8" bit but it is very time consuming and a PITA to say the least.

 

[mountainlake]

Yes that is whats left of the CAT after my 7/8" bit got done with it.

You can drill, pry and pull the cat out if you dont have a 7/8" bit but it is very time consuming and a PITA to say the least.

I use a 1 " drill bit. Steve

 

[RedFir Down]

I use a 1 " drill bit. Steve

If I remember right a 1" hole saw bit was a tad to big.

Where you using a traditional metal drill bit?

 

[BusyBeaver]

RedFir said he used a 7/8 hole saw. That's what I used too. Works perfectly.
BB

 

[mountainlake]

A 1`" fits good but looks like a 7/8 does the job just fine. Steve

 

[Nicutmafia]

Ok I'm pretty clear on the muffler mod with the exception of opening up the deflector. Any special instructions here?

As for the limiter caps, I have located these and just need to thread a drywall screw into them and they just pull out? Then there are some tabs I have to trim off them? I attached pics of the caps so maybe you can help me understand a little better. I also attached a pic of the saw. Thanks....

 

[M&Rtree]

I did the same to mine. My cousin talked me right out of the saw. He ported it and said he got greedy after awhile and end up over revving it. I had it 2 or 3 years was a great saw. Especially for the 80 bucks I paid for it. Power is similar to my 543xp.

 

[BusyBeaver]

Here's what I did:
BB

 

[Nicutmafia]

If I do these mods to my saw, will it in any way adversely effect the saw, like cause it to over Rev and blow up or anything like that? Would removing the limiter caps and re-tuning without middling the muffler accomplish anything? What I am trying to achieve is getting this saw to run correctly without having to worry about premature failure due to it running too lean. I wouldn't mind a bit of performance boost but that's really not necessary as I will only be using it to cut approximately 30 ricks of personal fire wood per year and also the occasional clean up. Thanks...

 

[Philbert]

Here's a related thread, FYI. Unfortunately, many of the photos have been lost.

http://www.arboristsite.com/community/threads/echo-cs-400-chainsaw-muffler-mods.129928/

Philbert

 

[jughead500]

I done a muffler mod on my buddys cs400 today i ground out the rear deflector behind the cat with a dremel and just drilled out the cat with a 7/8" drill bit.and only took out 1 of the sections on the front outlet.it really did bring it to life.even the small port before the cat would choke it out.i don't know how it breath through both it and the converter too.i still have to fine tune tomorrow.

 

[stubnail67]

I done a muffler mod on my buddys cs400 today i ground out the rear deflector behind the cat with a dremel and just drilled out the cat with a 7/8" drill bit.and only took out 1 of the sections on the front outlet.it really did bring it to life.even the small port before the cat would choke it out.i don't know how it breath through both it and the converter too.i still have to fine tune tomorrow.

pics of before and after??