Echo CS 400 dilemma

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Eagle_Adam

Forum smart but 2stroke stupid....
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Very long confusing story short....

I picked up a used echo CS 400 at an estate sale marked as a "non runner" for $25.

Thanks in large part to this forum I figured out someone tried at one time to do the muffler mod and carb retune, saying they failed would be nice.

After a couple nights of searching and reading I ended up cleaning up their butchered attempt of a muffler mod and replaced the fuel lines.

The carb retune is where im stuck, the PO littery turned the H & L screws all the way clockwise.... Where should I put them so I can get the saw to at least run enough so I can try my hand at tuning


Thanks in advance
 
Very long confusing story short....

I picked up a used echo CS 400 at an estate sale marked as a "non runner" for $25.

Thanks in large part to this forum I figured out someone tried at one time to do the muffler mod and carb retune, saying they failed would be nice.

After a couple nights of searching and reading I ended up cleaning up their butchered attempt of a muffler mod and replaced the fuel lines.

The carb retune is where im stuck, the PO littery turned the H & L screws all the way clockwise.... Where should I put them so I can get the saw to at least run enough so I can try my hand at tuning


Thanks in advance
First of all, you got a terrific deal, even if this turns out to be a parts saw for a second identical purchase. Because the saw was obviously set so lean, first pull the spark plug, drop the piston and shine a bright LED light down into the cylinder (I always need reading glasses for this part). You will only be able to see the exhaust side of the cylinder, but look for dark vertical lines that are possibly scratched into the cylinder wall. Just seeing some black vertical marks doesn't always mean the cylinder is scored, so the next step would be a compression test. If the cylinder and piston are good, you will get a reading of 145 - 150 psi, or there about, which means no worries. If you have the right tools, you could also remove the muffler and then get a better look at the piston for signs of scoring. The only reason I am advising to start with this test is because the saw was muffler modded. If the guy modded the saw and did not remove the limiters, odds are he scored the cylinder. As far as the muffler being butchered, don't worry about that. Pretty doesn't guarantee functionality, and ugly doesn't preclude it. If you remove the muffler, you will be able to see if the PO removed the catalyst from inside the muffler. It is hard to tell without seeing the muffler and using only what you have described so far.

Regarding the carb, first thing you want to do is remove the limiters (red plastic plugs with little winged stops on them). Dry wall screw (#6) usually works great. Lightly seat the jet screws. Next set the low speed jet (the one closest to the engine) about two and one half turns out CCW. Next Set the high speed jet out about 2 and 3/4 turns out. You might want to turn the idle screw up a little initially and then start the saw. These are only ball park initial starting settings for that saw, but if it is a runner, it should start up right away. At the recommended settings for this particular saw, you are now probably a little rich but close. After that, you can do the fine tuning according to many explanations on this website. Lots of good people on this website to help! Good luck. 2lumbarleft out.
 
First of all, you got a terrific deal, even if this turns out to be a parts saw for a second identical purchase. Because the saw was obviously set so lean, first pull the spark plug, drop the piston and shine a bright LED light down into the cylinder (I always need reading glasses for this part). You will only be able to see the exhaust side of the cylinder, but look for dark vertical lines that are possibly scratched into the cylinder wall. Just seeing some black vertical marks doesn't always mean the cylinder is scored, so the next step would be a compression test. If the cylinder and piston are good, you will get a reading of 145 - 150 psi, or there about, which means no worries. If you have the right tools, you could also remove the muffler and then get a better look at the piston for signs of scoring. The only reason I am advising to start with this test is because the saw was muffler modded. If the guy modded the saw and did not remove the limiters, odds are he scored the cylinder. As far as the muffler being butchered, don't worry about that. Pretty doesn't guarantee functionality, and ugly doesn't preclude it. If you remove the muffler, you will be able to see if the PO removed the catalyst from inside the muffler. It is hard to tell without seeing the muffler and using only what you have described so far.

Regarding the carb, first thing you want to do is remove the limiters (red plastic plugs with little winged stops on them). Dry wall screw (#6) usually works great. Lightly seat the jet screws. Next set the low speed jet (the one closest to the engine) about two and one half turns out CCW. Next Set the high speed jet out about 2 and 3/4 turns out. You might want to turn the idle screw up a little initially and then start the saw. These are only ball park initial starting settings for that saw, but if it is a runner, it should start up right away. At the recommended settings for this particular saw, you are now probably a little rich but close. After that, you can do the fine tuning according to many explanations on this website. Lots of good people on this website to help! Good luck. 2lumbarleft out.

Epicly perfect answer I was hoping for, thank you.

A few deatils to respond to your post:
- IMO the PO must have removed the muffler prior to drilling the two cockeyed, crookedass 3/8's in holes thru the cat
- while I had the muffler off to clean up the previous "mod" attempt I looked over the piston\cylinder wall and it looked fine to me.
- if the compression test kit I have has an attachment that will work on the saw I'll do the test, if not I'll be honest I probably won't
- already have the limiter cap off ;)


Hoping that later today I'll have some time and energy left to go see if she will fire up and tune for me
 
If the PO butchered a saw that's so easily modded.....wonder if he straight gassed it.

The CS 400 is a great little saw that really wakes up with significant gains with muffler mod and proven durability.

Hope the saw runs great for ya'.
 
Epicly perfect answer I was hoping for, thank you.

A few deatils to respond to your post:
- IMO the PO must have removed the muffler prior to drilling the two cockeyed, crookedass 3/8's in holes thru the cat
- while I had the muffler off to clean up the previous "mod" attempt I looked over the piston\cylinder wall and it looked fine to me.
- if the compression test kit I have has an attachment that will work on the saw I'll do the test, if not I'll be honest I probably won't
- already have the limiter cap off ;)


Hoping that later today I'll have some time and energy left to go see if she will fire up and tune for me


Great! If you had scoring, the damage to the visible portion of the piston wall would be instantly visible. Also, with the muffler off, you can view the intake side of the cylinder as well. Obviously that is clean as well, so you know the saw was not straight gassed. You can forget about the compression test. As long as you have the muffler off, why not finish drilling out the catalyst. Some individuals like the PO only drilled the two 3/8" holes, because they wanted the saw to warm up faster, plus it might be slightly quieter. On some saws, if you open up the muffler more than 80% of the ejection port size, you can actually lose power, but in my experience with the CS-400, I drill and grind out as much of it as I can. The smaller top steel plate is already reduced in size, so odds are, you won't be drilling that out as well (not necessary in my opinion). On the exhaust guide side of the muffler, you will notice the small vent holes, one larger and two smaller. I just open that area up into a neat little rectangle with a Dremel tool and an abrasive cutoff wheel. Finally, the "exhaust guide" has a restrictive inner baffle that I grind out with a vice grips to hold it, and a bench grinding wheel, then finish off the edges with a carbide bit and the Dremel tool. The #30 mesh factory screen works fine, but I cut a new screen from #20 mesh stainless screen to improve air flow even further. Remember to blow the muffler out with an air hose. Some people wash the muffler in warm soapy water and then blow it out. Just make sure there are no metal fragments left from your grinding activities. Some say you should wear a respiratory filter mask because of the carcinogens in the catalyst, so be forewarned. I don't know if it is true, but I wear a mask, just to error on the side of safety.

An additional note to other readers who try this, I have done the same operation with the smaller Echo CS-310 and CS-352 saws. I remove less of the catalyst on those saws just to keep noise down a little, and help them warm up faster. You will be surprised, as even the little CS-310 will cut like a 40cc Poulan.

Cheers: 2lumbarleft
 
Yep if you have no scoring your good finish the muffler mod remove all the cat and clean well.... then you need to tune it really fat like dogging in the cut fat.... then slowly lean it up till its cleans up when you hit the wood...then adjust the low and idle ... low for throttle response this is how i do it... some do it opposite but you need to tune it in wood fat and slowly creep up on the sweet spot....even if it takes a few time once you have it your good then if your in a cold area im not do it again 9n dead of summer....i retune mine anytime i think its running odd... but i kinda enjoy it....the cs 400 can be tricky take your time.... good score!there is no set screw that's perfect goes by temp and elevation ... tune in wood.
 
As an example i just returned a cs 310 when i changed bar size it was tuned for 14 inch i dropped to a 12.... and retuned....look at it as practice....the more you do it the more you hear it....
 
I would like to add one final comment on tuning. Some individuals may have invested in handheld wireless tachometers. I personally feel a tachometer is a very useful tool that I use to verify, or give a second opinion on my tuning skills in wood. I usually use the tachometer to speed up the tuning process on new saws by making initial adjustments on the rich side and then fine tune the saw in wood. I then recheck with the tachometer. A word of caution. Do not rely entirely on your tachometer. Even after you think your saw is warm, and you have performed WOT tests, that saw is still not as hot as after you have made several really long cuts in hardwood. Many times I have tuned a new saw like the CS-400 to 12,000 rpm initially. The saw has been running for at least five minutes or longer. I make several long deep cuts, pull the bar from the wood and immediately perform another WOT test, only to find I am revving above 12,500 rpm. In other words, my initial rpm assessment was incorrect because the saw was not really performing at peak temperature, and the saw needed to be slightly enriched. As Stubnail67 stated and to paraphrase, after you get skilled with tuning, you will find it useful to tune more often. However, if you are less inclined to tune due to changing temperatures or swapping out different bar lengths, it is better to tune a little rich than for top performance. In this case, I advise as part of routine maintenance to periodically pull a spark plug and inspect the top of piston piston, just to make sure you are not coking up. It will look like a rich black mat of fungi or felt on the top surface of the piston. This would be a sign that likely indicates that you are set too rich. With severe cases, your muffler will display signs of excess oil discharge. Naturally, always use a high quality 2 cycle oil. Don't cheap out with bargain bin products.
 
I'd start at 3 1/2 turns out on the adjusters, should be rich then. Some end up around 3 turns out when tuned good. Steve

Initial settings from the manual:

Low speed screw - 1 3/8

High speed screw - 2 3/4

Idle screw - 1 3/8 turn after first contact with throttle

If using a tach, the idle speed should be 2,600, ± 200 RPM

These are the short and to the point version of the answer I was hoping for, so thank you as well guys!

It’s 2:30am and I finally got sometime to myself and was able to get the carb and idle screw set approx to the posted initial factory settings. Unfortunately I’m not in the mood for a late night/early morning visit from my local boys in blue so I guess I’ll wait a few hours before attempting to fire up the CS-400. Once the suns up and the garbage truck has already woken up and pissed off the neighborhood then I’ll try my hand at tuning it under load buried, I was able to pick up some of white oak rounds just for the occasion. Until I hear the train wreck that is my garbage service I’m gunna see what I can do to improve the half dozen or so chains I have with this fancy new Stihl 2in1 chain sharpener/file I picked up yesterday. Wish me luck fellas
 
These are the short and to the point version of the answer I was hoping for, so thank you as well guys!

It’s 2:30am and I finally got sometime to myself and was able to get the carb and idle screw set approx to the posted initial factory settings. Unfortunately I’m not in the mood for a late night/early morning visit from my local boys in blue so I guess I’ll wait a few hours before attempting to fire up the CS-400. Once the suns up and the garbage truck has already woken up and pissed off the neighborhood then I’ll try my hand at tuning it under load buried, I was able to pick up some of white oak rounds just for the occasion. Until I hear the train wreck that is my garbage service I’m gunna see what I can do to improve the half dozen or so chains I have with this fancy new Stihl 2in1 chain sharpener/file I picked up yesterday. Wish me luck fellas


Steve has been advising many of us on echos and tuning them for a long time ...You cant go wrong with his information....like someone else said when im cutting in florida's heat I always have a screw driver and a 2nd saw with me just in case ...i wont push a saw that's hot ...i will pick up a fresh saw if i can not get it tuned for some odd reason....really the best time to tune it is when you have made some long cuts as said by another member here and i agree with him.... 2lumbarleft....have fun and use your common sense pull it out see if it idles.... for a few on the ground ...shut it off if its smoking alot something is not right....good luck and have fun....Sharp chain is your best friend also LOL.
 
Well gentlemen it’s a girl! I’m now a proud papa with a childish grin, cus this ***** screams ;) I’ve run a couple other CS-400’s before, none modded though. This ones a completely different animal tho!

Here she is in all her glory
 

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AND!!!

The timing gods smiled upon me today as well, the replacement part I’ve been waiting on in order to get little Ms Echo’s big brother back in the cut came today as well. Surgery was swift and successful so now my 044AVE is back in the mix :D
 

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They make quite the pair IMO
 

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This was taken a couple weeks ago when they we dropped off, and after a bit more dialing in on each saw I’ll be able to get started on these mammoths.

Thank you to each and every person that provided some insight on how to get my Echo up to par!!
 

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This was taken a couple weeks ago when they we dropped off, and after a bit more dialing in on each saw I’ll be able to get started on these mammoths.

Thank you to each and every person that provided some insight on how to get my Echo up to par!!

Impressive!!


Sent from my iPhone using Tapatalk
 
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