CS-590 will not idle

[samandothers]

Dave41A  I appreciate your stick-to-it-ness!  You will wrestle this down with the help of so many here.

Nolan1030  Welcome to the forum!

[Dave41A]

Have you done a compression check on this saw? If you have cylinder damage this would cause low speed issues. I work on two stroke outboards for a living and we always start with a compression check. A saw(or any motor) with low compression will have trouble pulling fuel at lower speeds.

Nolan:  Thanks for writing back.  I have not done a compression check, but it seems to have good compression when starting it.  I use the decompression button most times.  I can pull it under full compression, but it is noticeably more difficult.  Not scientific, but I don't have a gauge available to put on it.  Is there anything else I can do instead?  Thanks again, Dave

[Dave41A]

As a follow-up to anyone still reading this post, the long back-ordered parts finally arrived, and I installed them.  I have a new fuel filter, a new in-tank fuel line, a new fuel tank grommet, a new fuel elbow, a new fuel elbow to carburetor line, a new impulse line, and new fuel tank filler cap o-ring.  I changed the O-ring first, but then changed parts one system at a time to see if it made any difference.  In order:
1) New impulse line from crankcase to carburetor--no effect
2) New fuel filter--no effect
3) New fuel lines & grommet--no effect

So, after waiting a month, I have made no progress.  The saw starts reliably, and I can warm it up by running it at full throttle.  However, it will only idle for 7-8 seconds when the throttle is released.  A re-start and it does the exact same thing.  I can even count the seconds for it to die when releasing the throttle--always 7 to 8.

I had previously done a complete carb rebuild with a carb kit and it did not make any difference, either.

Any insight is appreciated.  Thanks, Dave

[samandothers]

Not cool.  Sorry it did not do the trick.  

[kenskip1]

David, From what I hear it sounds like at idle the crankcase is pooling with gas.Simply gas is flooding the engine out. At higher speeds this is not an issue as the mix is being drawn into the cylinder. But at idle in your case the mix is forming a puddle in the crankcase instead of going into the cylinder.This is just a theory so all you experts back off.Anyway David I would do a pressure check on the crankcase and see if you are able to locate this anomaly.Ken

[Dave41A]

David, From what I hear it sounds like at idle the crankcase is pooling with gas.Simply gas is flooding the engine out. At higher speeds this is not an issue as the mix is being drawn into the cylinder. But at idle in your case the mix is forming a puddle in the crankcase instead of going into the cylinder.This is just a theory so all you experts back off.Anyway David I would do a pressure check on the crankcase and see if you are able to locate this anomaly.Ken

I agree with you that this is a fuel problem and the crankcase pressure has something to do with it.  This all began when the impulse hose somehow got disconnected from the crankcase in the first place.  It is possible something got sucked in there and caused some damage, or simply plugged something.  Before the carb rebuild I did adjust the needle lever a little to keep more fuel in the diaphragm.  This got the idle up to maybe 11 seconds or so.  So for whatever reason it is not pumping gas at idle.
Is there any experiment or test I can do easily to check this?  I am running out of options, I am really hoping that Nolan is wrong.  Nothing against Nolan, but I really hope I do not have cylinder damage.
Thanks for writing back.  Dave

[Greenerpastures]

Take off muffler and look what the cylinder and piston look like.
You may have low compression, and getting the saw to start by
having way too much fuel going in, which will still be going in
when the saw starts, this will be masked somewhat at high rpm
but at idle will flood the saw.

When the saw was running with the impulse line off, maybe
damage was caused, you won't know unless you look into the
cylinder or as others said do a vacuum and pressure test.

When you have the muffler off you could modify it if you like.

Hope am wrong too, and it's something simple, my mind reflects
 back to your mention of throttle and choke linkage settings, go
there again, disconnect the choke to ensure it's not still on,
check the throttle body closes and opens in full, that it's not closed
too much at idle, the linkage should have been right from new, so
what knocked it off, and what knocked the impulse line off.

[Dave41A]

Take off muffler and look what the cylinder and piston look like.
You may have low compression, and getting the saw to start by
having way too much fuel going in, which will still be going in
when the saw starts, this will be masked somewhat at high rpm
but at idle will flood the saw.

When the saw was running with the impulse line off, maybe
damage was caused, you won't know unless you look into the
cylinder or as others said do a vacuum and pressure test.

When you have the muffler off you could modify it if you like.

Hope am wrong too, and it's something simple, my mind reflects
back to your mention of throttle and choke linkage settings, go
there again, disconnect the choke to ensure it's not still on,
check the throttle body closes and opens in full, that it's not closed
too much at idle, the linkage should have been right from new, so
what knocked it off, and what knocked the impulse line off.

OK, Muffler is off.  I am assuming what I see here is not good.  There is a clear bright spot worn on the side of the piston, extending from the rings down the skirt about half way, maybe more. It is hard to see in there, but it looks like the far side (intake side) of the cylinder is similar.

 

[ladylake]

  May as well pull the cylinder off and see .  Steve

[Real1shepherd]

You should buy a compression tester...they're not that expensive. My guess from the last pic and all that's been written is your compression is low due to cylinder/piston transfer damage. If your saw ran too lean at some point, the damage you see could easily have happened.

It's possible your cylinder could be cleaned with acid to get rid of the aluminum tranfers and you just replace the piston/ring.

Kevin

[lxskllr]

Before getting too carried away with it, it might be worth considering a new saw. It costs $400 new. If you're getting into replacing pistons/cylinders that's gonna start racking up the dollars. A compression tester would be generally useful, so personally I'd start with that, then consider where to go from there.

[Dave41A]

Thanks to everyone who has responded.  The saw has a "Dec 2015" sticker on it...I am going to call the local Echo dealer/repair and see if they will agree to take it under warranty.  I bought this saw, which for me was a big step up in quality and price from the "homeowner" saws I had been using, because of the warranty and (when that expired) the ability to change the piston separate from the crankcase, as wiped cylinders/pistons was what had doomed the cheaper saws.  I have done business with this dealer before, and hopefully the fact that I had put a carb kit in it and replaced the fuel and impulse hoses won't invalidate the warranty.  They are apparently closed today (Memorial day and/or local COVID-19 restrictions).

If that fails then I will look into replacing the piston ($30 or so), and cleaning up the cylinder to see if it can be salvaged.

Thanks also for the suggestion on "too lean."  The carb had had the limiter caps on it, and I had not touched their adjustment, so it must have come this way from the factory.  I am guessing blow-by while cutting over-pressurized the crankcase and blew the impulse hose off. 

Thanks again to everyone for their patience while walking me though the troubleshooting.  This was my first in-depth work on a 2-cycle, and learning their ins-and-outs relative to their 4-stroke cousins has been educational.  Dave

[Greenerpastures]

Hi Dave41A, sorry to see the damage to the cylinder, that impulse line being off was a big problem. not sufficient fuel getting to the engine,
But in all honesty unless you knew what to listen for and not run the saw as soon as you noticed it was off it's tune, enough said.

But, you don't need a new saw, you have put a lot of new parts on,
Lines carb etc, I would take the cylinder off, it may well clean up,
and all you will need is a piston, rings, ORIGINAL snap rings to hold
the piston pin in, and a base gasket, still way cheaper than buying a saw,
you could do all this yourself, and people on here will be able to help
with advise re running it up, it may not end up perfect, but it will be
so close it won't matter, and will cut plenty, it could be replaced and
kept as a stand by if the need ever arises, or you could sell it and
upgrade with a clear conscience.

[Dave41A]

Hi Dave41A, sorry to see the damage to the cylinder, that impulse line being off was a big problem. not sufficient fuel getting to the engine,
But in all honesty unless you knew what to listen for and not run the saw as soon as you noticed it was off it's tune, enough said.

Greenerpastures:  Thanks.  With the impulse line off, it would not run at all--neither idle nor full throttle.  I am thinking the only sound it must have made when that line came off was the sound of a saw suddenly quitting.  Since then, I could only get it to briefly run at half choke, and I certainly wasn't cutting any wood with it that way.  It is possible that I did the piston damage myself while attempting to get the saw to run with the impulse line off.  I certainly pulled the starter cord enough times.  But I certainly wasn't operating it.
I'll see what the dealer has to say about warranty work and if the answer is "no," then I'll proceed with the new piston and cylinder salvage attempt.  I'll be sure to post pictures of what I find if I go that route.  However, if the dealer will cover the work and parts, then I'll happily agree to what will be an essentially all-new saw just shy of its 5-year old mark.  Either way, I'll post here for advice on tuning the carb, as it is now apparent to me what damage "too lean" can do. 
Hopefully I'll have an answer tomorrow from the dealer.  Thanks again, Dave.

[Greenerpastures]

I agree, doesn't take much to damage them when running lean
or dry as you tried to get fuel through the cab. I always put in an old plug
when engines are acting up at startup, take it out after a few pulls
to see if fuel is present, if not, I go no further until I find out why,
no fuel = no lubrication in out 2t engine.

Fuel air and spark, if you don't have them all, it's not happening.

Hope you get that saw back to life.

[Greenerpastures]

Before getting too carried away with it, it might be worth considering a new saw. It costs $400 new. If you're getting into replacing pistons/cylinders that's gonna start racking up the dollars. A compression tester would be generally useful, so personally I'd start with that, then consider where to go from there.

That's not a bad price, €739.00 here, never looked for a cheaper price as I can get a cs620 for the same money.

[Dave41A]

For the benefit of anyone still reading, the service department got back to me yesterday and today.  They are claiming the saw is "beyond repair" and is not covered by warranty.  I asked them to write the reason why they came to this conclusion on the receipt when I come to pick it up.  I'll post back when I get their reasons, but the explanation they gave me on the phone ("you had bad gas. when we opened the fuel tank it smelled horrible") is not encouraging.  This is too bad as one reason I got the saw was the 5-year warranty.  I bought it new in August of '16--less than 4 years ago.

[kenskip1]

Dave, I would challenge there decision.As long as it was fresh mix you should not have had a problem. This is simply a way to get them off the hook.Who made the decision? Some young person with less than a years experience? It all comes down to the mighty dollar. Personally I would attempt to make the repair myself on the other hand if your friendly dealer is a smart ass I would unload both barrels on him. Threaten him that you will call the regional office.Sometimes the squeaky wheel gets the grease.I have been following this post from the beginning, Ken

[Dave41A]

Dave, I would challenge there decision.As long as it was fresh mix you should not have had a problem. This is simply a way to get them off the hook.Who made the decision? Some young person with less than a years experience? It all comes down to the mighty dollar. Personally I would attempt to make the repair myself on the other hand if your friendly dealer is a smart ass I would unload both barrels on him. Threaten him that you will call the regional office.Sometimes the squeaky wheel gets the grease.I have been following this post from the beginning, Ken

Thanks.  I appreciate the continued interest.  They had originally called me two days ago with an estimate of $350 to $360 for repair.  I only paid $360 for the saw when new.  This was on Tuesday, 6/16/2020, and they made the claim of "bad gas."  I asked "How did you reach this conclusion?"  Their explanation "When the mechanic opened the fuel tank, it smelled horrible."  I then clarified that it could not be bad gas, and that they should double-check with the mechanic, who must be mistaken.  They called me back the next morning and told me "it cannot be repaired here, by us."  They still insisted that it was not covered by warranty, but declined to identify a reason, or point out what I had done wrong.  So this morning I went in to pick it up.  The service desk reverted to their "bad gas" explanation.  I had them write this on the receipt.  They wanted to charge me $22.50 for having the mechanic look at it, but I declined to pay.  They didn't push the point, and I took the saw and went home.  
I am going to write to ECHO directly.  I'll post later with how that went.  For anyone in the Erie, PA area, please beware of the service desk at the local "signature elite" ECHO dealer.  I could not be more dissatisfied.  Dave

[Real1shepherd]

IPL=illustrated parts listing. Google is your friend. In almost all saws, unless they are rare/oddball, an IPL can be found for your model.

Sorry, just realized I answered a question on the first page.:

Kevin

[Dave41A]

IPL=illustrated parts listing. Google is your friend. In almost all saws, unless they are rare/oddball, an IPL can be found for your model.

Sorry, just realized I answered a question on the first page.:

Kevin

No problem.  For what it is worth, Google took me as far as "abbreviations.com," which lists 46 different meanings for "IPL," ranging from "Internet Public Library" to "Intellectual Property Law" to "Intense Pulsed Light."  However, "Illustrated Parts list" is not there, but neither is "India Pale Lager," which is what I am thinking about right now.  Dave

[Hilltop366]

I have had the shoe on the other foot having been a saw, motorcycle, atv and personal watercraft dealer 30 years ago. The dealer can be in a tough spot between the manufacture/distributor and the end user. They have no way to know what has happened to a saw at the manufacture or after it left the shop with the customer and it is sometimes difficult to pinpoint a cause without spending lots of time, if they smell rotten gas that is going to be their first assumption.

As far as the pulse line falling of it is hard to know if it came off all at once or stayed on the end of the fitting giving you enough fuel to run but not enough to have the proper amount and then came off when you were working on it or just cane off when you were working on it.

If no joy with the warranty department at ECHO and you are inclined to do a bit more work you could remove the cylinder (if the repair shop did not) and see what it really needs to get the saw going again. If you are confident that the pulse line was the cause of the piston fail and you can get by with cleaning up the cylinder and buying a new piston, rings, w/p clips and gasket you could be on your way to sawing again. It would be up to you to decide if it will be good money after bad.

[Real1shepherd]

IPL=illustrated parts listing. Google is your friend. In almost all saws, unless they are rare/oddball, an IPL can be found for your model.

Sorry, just realized I answered a question on the first page.:

Kevin

No problem.  For what it is worth, Google took me as far as "abbreviations.com," which lists 46 different meanings for "IPL," ranging from "Internet Public Library" to "Intellectual Property Law" to "Intense Pulsed Light."  However, "Illustrated Parts list" is not there, but neither is "India Pale Lager," which is what I am thinking about right now.  Dave

Well, I got this far, but you need your serial# to go further:
https://www.partstree.com/models/cs-590-echo-chainsaw-parts/

Kevin

[Dave41A]

I have had the shoe on the other foot having been a saw, motorcycle, atv and personal watercraft dealer 30 years ago. The dealer can be in a tough spot between the manufacture/distributor and the end user. They have no way to know what has happened to a saw at the manufacture or after it left the shop with the customer and it is sometimes difficult to pinpoint a cause without spending lots of time, if they smell rotten gas that is going to be their first assumption.

As far as the pulse line falling of it is hard to know if it came off all at once or stayed on the end of the fitting giving you enough fuel to run but not enough to have the proper amount and then came off when you were working on it or just cane off when you were working on it.

If no joy with the warranty department at ECHO and you are inclined to do a bit more work you could remove the cylinder (if the repair shop did not) and see what it really needs to get the saw going again. If you are confident that the pulse line was the cause of the piston fail and you can get by with cleaning up the cylinder and buying a new piston, rings, w/p clips and gasket you could be on your way to sawing again. It would be up to you to decide if it will be good money after bad.

Hilltop:  Thanks.  I did explain what happened when I took it in--including all the work I had done (fuel and impulse lines, filter, carb kit)--but the fellow behind the counter didn't strike me as the sharpest tooth on the chain.  His notes on the service order invoice are crude at best.  I can understand the assumption that it was bad gas, but after I explained things a second time over the phone, they changed their story--and then back again the next day. I am sure you never treated a customer this way.
I will respectfully disagree that the mechanic has no way of knowing what has happened to a saw.  They could have asked me, the owner. To make an assumption based on one thing (and erroneously at that--I had just put fresh gas in it!) and then attempt to hit the customer with a $350 bill rather than spend the time to properly diagnose the true cause of the problem is shoddy work at best, and unscrupulous business.  Even if the repair was outside of the warranty period, I would expect that for the period of skilled labor I was billed for that the mechanic would do more than sniff the fuel tank.  Since you were a dealer, I am sure you experienced some customers abuse this--lying to the mechanic when in reality they had really mis-used the saw--but I am not some other customer.  I am not saying my trouble-shooting and mechanical skills are perfect--this certainly had me stumped for several days.  But I will state that I was honest with them about what I had done, up-front.  There is a difference between a mechanic saying "in my opinion you damaged the saw by repeatedly trying to start it with the impulse line off" and one who makes stuff up or changes stories.  I'll accept bad news as long as it is honest bad news. 
Regarding the pulse line, I was able to remove the air filter and peer down the small gap between the handle assembly and crankcase.  I could see the impulse line dangling there.  This was before I disassembled the saw further, so I can assure you it did not come apart when I was working on it.
I am reaching out to ECHO USA to see if they can remedy this.  Sorry if any of this comes across as strong, but I haven't found that "IPL" yet (second definition from earlier today), which I clearly need.  Best regards, Dave

[Dave41A]

IPL=illustrated parts listing. Google is your friend. In almost all saws, unless they are rare/oddball, an IPL can be found for your model.

Sorry, just realized I answered a question on the first page.:

Kevin

No problem.  For what it is worth, Google took me as far as "abbreviations.com," which lists 46 different meanings for "IPL," ranging from "Internet Public Library" to "Intellectual Property Law" to "Intense Pulsed Light."  However, "Illustrated Parts list" is not there, but neither is "India Pale Lager," which is what I am thinking about right now.  Dave

Well, I got this far, but you need your serial# to go further:
https://www.partstree.com/models/cs-590-echo-chainsaw-parts/

Kevin

Kevin: Thank you.  I worked through "Jack's small engines" website and ordered the fuel system components that I needed (fuel lines, filter, carb kit, etc.) on a similar "illustrated Part List."  This was before I had looked in the muffler and found the damage.  I have ordered from partstree before (for other projects, years ago), and will typically shop around from the various sources to find the best price.  However, I had always called the diagrams "exploded parts diagrams" and had never used nor heard the "IPL" abbreviation until this episode.  You learn something every day.  Thanks again and Happy Summer. Dave