Looking for info on Echo CS-510 Carburetor Settings

[privatear2001]

Hi all. I have an Echo CS-510 that I purchased on eBay last year. I've had to rebuild a lot of it (new bar, new chain, new filters, new chain tensioner, etc) even though the guy advertised the saw as "ready to go, but might need the bar and chain replaced." It was far from that. I had to put a lot of new stuff into it. But I like resurrecting old equipment so I do the best I can. Better than it being in a landfill, I figure, if I can get a few more years use out of it.

Anyway, this saw has been fighting me from the first. I can't seem to find reliable information on the high and low speed idle, for one thing. I think HS Idle is between 11000-13000, but not sure of that (I think these were high-revving saws). I don't know which hole (there are 4 on the throttle "cam") the throttle linkage originally went to. Right now it is in the farthest hole which allows the throttle to open to maximum position, but checking idle speed with a Stihl EDT7 tach, sometimes it was getting up over 14200, which seems way too high; but if I turn HSI screw back, the saw bogs down. So I'm thinking if I go to the next hole, when I have the throttle opened all the way, the high speed idle shouldn't go over 13000 WOT. Does this seem reasonable?

So I was wondering if anyone had the proper specs for this saw, including:

• Initial turn-outs (from fully closed) to start with, for the H and L speed screws (no limiters on them)
• High and low speed RPMs I should expect to see when "tuned in"
  
• which hole the throttle arm should be in on the throttle "cam"

Any other info on how to tune up this saw or insights into something I may be missing here would be greatly appreciated. Thanks for any help you might render. I've been reading stuff on here for a couple of years which has helped me with other saws before in the past. So thanks for this forum. All the best.

 

[Cliff R]

I have one here and have been using it for at least 10 years, very strong runner for 51cc. The only thing I did to mine was to open up the muffler just a tad as they have an internal pipe that is a bit restrictive.

You don't need a tach to set the "L" and "H" screws. Get the saw warmed up, set the idle speed low enough so the clutch doesn't turn the chain but fast enough no tendencies to stall out coming out of a cut. Fine tune the "L" screw to highest idle rpm then CCW till it just starts to slow down and your done.

Set the "H" screw plenty rich and start making cuts. It should be heavily "four stroking" and down on power. Lean it up with each cut until it cleans up nicely when load is applied but instantly four strokes out of the cut. There is no rev-limiting feature on the CS-510's that I know of. They are pretty high rpm saws and very impressive for power when you get it set correctly......Cliff

 

[ray benson]

Took this out of an Echo service manual, Saw speeds and carb settings. Added a small clymer service manual

 

[privatear2001]

I have one here and have been using it for at least 10 years, very strong runner for 51cc. The only thing I did to mine was to open up the muffler just a tad as they have an internal pipe that is a bit restrictive.

You don't need a tach to set the "L" and "H" screws. Get the saw warmed up, set the idle speed low enough so the clutch doesn't turn the chain but fast enough no tendencies to stall out coming out of a cut. Fine tune the "L" screw to highest idle rpm then CCW till it just starts to slow down and your done.

Set the "H" screw plenty rich and start making cuts. It should be heavily "four stroking" and down on power. Lean it up with each cut until it cleans up nicely when load is applied but instantly four strokes out of the cut. There is no rev-limiting feature on the CS-510's that I know of. They are pretty high rpm saws and very impressive for power when you get it set correctly......Cliff

Cliff, Thanks for the reply on this. I really appreciate it. Its great to have someone to talk to who has one of these saws. I'm not sure what the term "4-stroking" refers to, though. Also, I was wondering if you could check your carb and see what hole the throttle link is in (there are, I think, 4 holes in the cam). I'm not sure that I'm in the right hole because I previously removed the carb when I first got the saw and wasn't sure what hole the linkage had come out of. When trying to adjust the saw, it wouldn't work right at the high speed setting. It would just keep bogging down. When I got it to a point where it didn't lose power, the RPM was way too high. That's why I think I need to know what hole the throttle linkage attaches to on the cam. I think I did get the high speed set right at one point, but the throttle opens way too wide on the setting I have it now. When I was at 3/4 open throttle with HS "right", it seemed to run where I wanted it. If I set the HS needle too low, the saw would bog down and I couldn't keep it going at WOT. Again, thanks for your reply. Look forward to interacting more with you guys. I know a little bit about some of this stuff, but I'm not as up on it as I wish I was.

 

[president]

I have one here and have been using it for at least 10 years, very strong runner for 51cc. The only thing I did to mine was to open up the muffler just a tad as they have an internal pipe that is a bit restrictive.

You don't need a tach to set the "L" and "H" screws. Get the saw warmed up, set the idle speed low enough so the clutch doesn't turn the chain but fast enough no tendencies to stall out coming out of a cut. Fine tune the "L" screw to highest idle rpm then CCW till it just starts to slow down and your done.

Set the "H" screw plenty rich and start making cuts. It should be heavily "four stroking" and down on power. Lean it up with each cut until it cleans up nicely when load is applied but instantly four strokes out of the cut. There is no rev-limiting feature on the CS-510's that I know of. They are pretty high rpm saws and very impressive for power when you get it set correctly......Cliff

good instructions Cliff

 

[privatear2001]

Took this out of an Echo service manual, Saw speeds and carb settings. Added a small clymer service manual

Thanks Ray. I love service manuals. Appreciate it much. Can you tell me if the Echo CS-510EVL has the same specs as the Echo CS-510. I wonder what the "EVL" designation means, or what the difference in the two are. Mine is just a plain old "CS-510". I think the "CS-510EVL" was a generation earlier, perhaps? However, I was still wondering if the specs might be mostly the same. Its a place to start, anyway. Thanks again. All the best!

 

[ray benson]

evl - electronic vibe less - echo does show 2 ipls for the 510

 

[privatear2001]

evl - electronic vibe less - echo does show 2 ipls for the 510

Thanks for those, Ray. I knew they were kind of a different saw, so I wasn't assuming right off that they would have the same settings. I'm trying to reach a definitive bunch of settings for this saw, which I'm sure I'll be able to do with the help of people here and trial and error. If I can get it running well, I'll take note of where everything is set. Unfortunately, I probably can't get at the saw til next week sometime. Its plenty cold out there right now. But when I get the chance, I'm going to take it apart on the bench to try setting the throttle linkage one hole down, I think.

 

[Cliff R]

The EVL will not be the same model, those are "old" designs and about half the power of the modern CS-510 with the upright closed port piston ported P/C.

The carburetor linkage should be in the hole that provides base idle against the speed screw and FULL open at WOT. Nothing else will work correctly.

The "H" speed screw is your "rev limiter" so make sure it is "four stroking" or missing at no load when you are at WOT. Sounds like it's a bit lean if I understand what you posted above......Cliff

 

[privatear2001]

The EVL will not be the same model, those are "old" designs and about half the power of the modern CS-510 with the upright closed port piston ported P/C.

The carburetor linkage should be in the hole that provides base idle against the speed screw and FULL open at WOT. Nothing else will work correctly.

The "H" speed screw is your "rev limiter" so make sure it is "four stroking" or missing at no load when you are at WOT. Sounds like it's a bit lean if I understand what you posted above......Cliff

Thanks so much for your replies, Cliff. It sounds like you know your stuff!

Well, with where the linkage is set now (in the top hole on the throttle "cam"), if I get the HSI open where it seems "right", at WOT, the saw just screams and the tach shows 14200+ RPM. If I open the throttle to about 3/4, that sounds just about right. Setting the linkage back one hole should set the upper limit to where I want to be. I think that I have gotten the HS screw correct, but the linkage is in the wrong hole, so the saw goes way above what it should in RPM at the upper end.

I did get to speak to what sounded like a 20 year old-ish young woman at Echo "tech support" once a couple months ago. And she started looking things up and said the High Speed RPM should be no more than 13000 RPM. But she didn't sound confident in that knowledge, or even knowledgeable on the subject at all, which is why I came on here. [Unlike when i called EFCO (Olympyk) and they had people there who really knew their saws, it seemed]. Echo seems to have no tech support that I can tell. But she did try.

This forum is a great tool because I know I have knowledgeable people on here who have used this saw and even if I can't explain exactly what is happening, this forum at least helps me run through a logical process of thinking of why things might be working the way they are. Sometimes when I can't explain why things happen, I tend to get in the frame of mind that its "unexplainable" or because of "gremlins"... but that's not usually very helpful in developing a practical solution to the problem. But sometimes I almost do think things are jinxed or something. So its helpful when you guys show me it isn't magic and it obeys some natural rules!

[As an aside, I have another chainsaw (Husky I think) that has compression and spark, gets fuel (the piston is always wet) yet will not start! even on ether!!! Maybe I'll post that one when I pull it out again sometime. Cannot figure that one out. Gremlins??? ]

 

[Cliff R]

The linkage is NOT used to control full throttle/no load rpm's, that is going to be done with the "H" speed screw. The linkage is set so the throttle plate in the carb opens all the way to 90 degrees, then returns against the idle screw when released.

I haven't had a tach on mine but can tell you from running many of these saws it's running just a tad over 13,000rpms or so no load and four stroking nicely out of the cut. It "cleans up" the instant you put load on it, and runs very strong for 51cc. It's on par for power with my closed port Husqvarna 55's but has a smoother/broader power curve, so basically just "grunts" a little better when you push it real hard.

Makes a great firewood saw, and happiest with an .325 18" bar and semi-chisel chain on it......Cliff

 

[privatear2001]

The linkage is NOT used to control full throttle/no load rpm's, that is going to be done with the "H" speed screw. The linkage is set so the throttle plate in the carb opens all the way to 90 degrees, then returns against the idle screw when released.

I haven't had a tach on mine but can tell you from running many of these saws it's running just a tad over 13,000rpms or so no load and four stroking nicely out of the cut. It "cleans up" the instant you put load on it, and runs very strong for 51cc. It's on par for power with my closed port Husqvarna 55's but has a smoother/broader power curve, so basically just "grunts" a little better when you push it real hard.

Makes a great firewood saw, and happiest with an .325 18" bar and semi-chisel chain on it......Cliff

Thanks, Cliff. I'll forget messing with the linkage and try your recommendations next week and see how she sounds. A friend of mine was able to tune her in good once, and she worked wonderfully for the first day I took her out, and then began bogging down again on subsequent uses. Can the high and lo speed idle screws back themselves off and come out of adjustment? I wasn't able to get her tuned back in like he was. So i figure i have to learn to fix it myself so i can fix it in the field when he isn't around. He also thought the saw ran too high when he had tuned it, but maybe it was in spec, as we didn't realize this saw ran at such high RPMs in the first place. You mentioned that you modded your muffler. Is that in another thread on here?

 

[Cliff R]

The factory carb has limiter caps on the L and H screws. The screws should hold their adjustment even if the limiter caps were removed.

The muffler mod on those is pretty easy. Remove the muffler and take a look inside it. Been a few years but there will be an internal pipe that puts a big restriction in it. Can't remember exactly how I opened it up but it wasn't very difficult and a nice wake up call for that particular saw........Cliff

 

[privatear2001]

Hey Cliff (and the rest of the fellers on here):

This one could not be adjusted to work properly with its caps on. Not enough play either way... maybe about 1/4 turn each, if that.

I messed with it the other day and between me and my friend, we got it tuned in pretty good. It still starts up with a spinning chain sometimes. and it still has some "boggie-ness", but it is quite useable now and that may work its way out. A lot better than what it was. It may also lose this tuning the very next day I use it as it did before. Not sure what caused that. May just need a rebuild kit to try rebuilding it. Seems like it had a lot of power. Cut up the Locust I'd felled with the smaller saw a couple weeks back in no time at all. Its nice to have a functioning saw... if only I can keep it that way. Great instructions, Cliff, btw.

Thanks for all your input. Haven't tried the muffler mod yet. Saw seems to have a lot of power as it is. Despite its shape when I first got it, I don't think it was too abused. Hopefully there's still a lot of life left in it.

Chris