always look forward to seeing more on the CS-590, as someone who owns a stock one. once you sort out how to make it sing, you will have a lot of owners, like myself, who will want you to modify them.
For work we always used professional Stihls. I loved them, although starting them was always a temperament issue based on weather conditions. And personally, I don't like the choke on stihls. But for my personal saw, I purchased the Echo cs590 (based on cost) and it's been a great running little beast. I feel that they aren't refined like a Lexus, more like a Toyota Camry from the late 90's. You know, when you could work on them and afford one, and it lasted forever. Hope you get that beast working the way you want.
That’s a great perspective. I have some echo equipment, along with some stihl pro, and husqvarna xp. My echo leaf blower is just lean and apparently they did a better job hiding the screws. The 266 weedwacker punches above its weight. 26cc outdoes an 80’s 28cc echo and almost keeps up with a 32cc multi head JD (homelite?) it doesn’t have quite as much torque, but the ease of loading line makes up for it. I can still run low rpm and burp it for brush, or know it will spool up even in a hay field.
i dont know why everyone says stihls are hard to start. I never have issues getting mine started. Starts reliably cold or hot, regardless of how long its been since the last time it was run... if your saws arent starting easily, its not the saw, its your tune
I ported my cs440 per the tin man channel. It's only a 45cc saw. I put the exhaust at 103, intake at 71, and didn't touch the transfers at 127. The ends at 154 exhaust duration, 24 blowdown, and 142 intake duration. The saw runs great. About 11,000 rpm in the cut. Thanks alot Tinman. Maybe this will help.
I think he raises the transfers too, and aims them at the intake. I also don't think he raises the exhaust roof as high as you did ... but you better ask him. His saws run awesome though!
Love the build. One thing I always try to tell myself, if I fix a problem that I created, it’s still a win. I can’t wait to see you win! Stay warm tinman
Hello Tinman, I own a stock CS-590 and found your channel on a random search for my saw and now I'm hooked. You are my favorite saw nerd! I don't fully understand 2 stroke design but I love to listen to your porting and customizing theories. It's fascinating what you have learned from porting such a variety of saws. As you describe what you are seeing in the design of the 590 I wonder.....will the echo engineers talk to you? What happens if you pick up the phone and ask them about the things you are proposing?
Hey Tinman, you raised the exaust 10 deg to 104 . Squish is perfect, but with 10 deg less compressionstroke, you loose a lot static compression. I think around 25 psi and that will be bad for torque and won’t make it zippy. Base Cut or better a pop up could compensate the less compression issue Maybee that is also part of the issue on that Saw. Kind Regards from Germany Keep doing , you will get it rippin 👍 Bye
Hi Tinman. Great video and quite informative. I have never ported a saw, but you make me want to try it. Stay safe and warm and keep these great videos coming.
Howdy Tinman! It’s been good weather here in northern Arizona. Some snow and ice, but 70F and sunny right now. Just picked up a cs590 Timberwolf based on your videos. Only planning to mod the deflector and adjust the carb for my homestead and farm saw needs.
AZ Highland, my cs590 took about 10 tanks to break in. Then it ran like a completely different beast. My suggestion is to just run it for a while before porting it or adjusting the carb right away.
IMO you can't beat e'm for the price! Squish on mine was .041, base gasket delete yielded .029 . Did bg delete and muff mod before first full tank, tuned slightly rich and left it alone for a while. Mine woke up on the 8th tank. Then I made it an Ironhorse style pipe... WOW, what a difference! It feels like it gained 15+% power😃 has no problem pulling oregon exl on a 24" bar! Great farm/ranch duty saws, that respond well to simple mods.
@@bobbyslavo9722 Complete agreement. Although I'm a professional tinker. I'm retired now and for fun I work on 2 stroke engines, machines like 1970's mopeds, scooters, lawn equipment and of course, chainsaws. I've figured out a while ago, that "If it was a just a little faster" mentality never changes .
To confirm your suspicion a smaller carb should limit the charge in the crankcase and not exceed the limit of the transfer. It would be interesting to see if a small carb or restrictor plate would clean it up in the cut.
I've been running my new echo 590 for two months now and it was a good saw from day one but it hasn't done anything but get better and better all the time , I'm thinking about selling my Husqvarna 61 and buy another 590 !
A Great learning experience for all. An amazing mechanic once told me his biggest advice is to be patient and humble. He told me that when you are stuck, step away and be patient. It's amazing how that works, but it does!
I for one, enjoy the weather updates👍 always been a little bit of a weather nerd. Good to see the CS-590 getting some more attention! Would be awesome if it woke right up with a little transfer port reshaping. Wouldn't be surprised if it does!
The reason that echo has the secondary transfer as big as they do. Because of emissions notice how it is aimed at the exhaust. They want as much spent exhaust out as much as possible for emission standards. I would raise both transfers equally try 5 degrees first but try to aim the primary toward the intake.
Over a month of-20 C for coastal B.C. That’s like 40 below 78% humidity and wind . Now it’s raining all the metal roofs have slid off Great advice as always thanx
Hey tinman here in Nova Scotia we are going from a plus two Celsius to a high tomorrow of minus thirteen Celsius with a windchill of minus twenty six Celsius. Gotta love them nor’easters. Your channel is very ensightful.
Been watchin since the XL76 build, first comment... One of your best vids on theory. 👍🏻 More drawings and think-through explanations please. Great, great vid!
Logic makes sense, draining the bottom end sooner should reduce pressure build up. Can wait to see it all come together. Excellent stuff once again. TC Tinman Mahalo 🤙🤙🤙... Tdawg.
Sounds like a good plan Tinman. In the other videos for this saw it seemed tied up and not running free. I think you have it. Good luck with it. We will be watching. Thanks
Tinman, what about lessening the overall intake timing and running a smaller carb, but not making any other changes? From your explanation, it seems as though keeping longer blowdown would increase dynamic compression, thereby increasing performance.
Carbs are generally oversized, but if it’s right sized it still doesn’t restrict flow until WOT. I just bought one for a stihl, ms 210,230,250 all use the same one. 4-stroke kohlers are the same 12,14,16hp all use the same carb.
So damn fascinating watching this, thanks for posting these Tinman!! The echo transfers are insane, I'm happy working on 660 transfers but wouldn't dare touch my 590's uppers!! Have you studied the 7310's uppers yet, where the secondary is so wide they had to bridge the port? Crazy awesome!! My understanding is that the 2 transfer channels are achieving different things, IE the primary is "helping finish exhaust-expulsion" while the secondary is "refilling the chamber for the next stroke", so far as I understand it after reading Jennings "2 stroke handbook"! Still fascinated and honestly I suspect a LOT of the final transfer design of a saw like these echo's is done in more of a 'trial&error on the flow-bench" approach, than in a mathematically-derived approach (would love your theories/thoughts on this!) Re Velocity...dogging-out the lowers will certainly achieve higher velocity of charge-dispersement so that may not be helping you (though mine are dogged at least as much as yours..though I didn't even look at the uppers(you'd said not to, in the videos ;D )) In Jennings' book he makes a point to keep bringing up velocity but it seems like it's pretty strictly / normally a thing relating to loop-scavenging, though of course the extremes of anything here will result in "short circuiting"/carb spitback/excessive loss of charge through muffler. "Widening the intake will reduce [potential]velocity of the intake-tract, therefore reducing case-pressure" I'm not positive this is right, I defer to you of course but I think that's inaccurate, here's why: While velocity can indeed be changed by port-shaping, widening wouldn't "reduce crankcase-fill" because *that* is a *direct* correlate of the unswept(swept?)volume of the jug that MUST be moved for the piston to move & comply w/ physics.....put in your analogy, "The syringe will still dispense 30CC if you depress the plunger that much, regardless of width of the syringe or the girth of its needle", because depressing 30cc from it FORCES this. MY understanding was that this is how the 2-stroke jug functions insofar as "flow volumes", and that BOTH velocity & turbulence are very VERY much secondary-considerations, not unimportant by any means but not remotely as-important as displacement//rpm, but far more important for the "loop scavenging effect" that drives our lil 2-strokes, in fact if I'm reading Jennings' book correctly then your idea of "widen the intake port in this instance" would actually HURT you, because as you get to higher RPM the total-throughput of your wider/larger intake port will be of GREATER significance than any velocity attributes could ever effect (if that's even what the intake-velocity reduction achieved, as I understand it a velocity reduction would be for efficiency of loop-scavenging IE less intake going-out the exhaust port, since a given volume IS gonna come out of that intake *based-upon* piston-displacement during the stroke, and our battle always seems to be "keeping it in the jug" especially if the muffler isn't on-point which sadly I'd say applies to MOST powersaw-tuners' mufflers :/ Had actually discussed this case when I had the good fortune to speak with Kensie and I was surprised he didn't agree (didn't disagree either, I don't think, but certainly didn't come across like he thought it had much validity) that this is a problem of muffler.....you still have a big hole in your rear-portion of the muffler, automatically making your saw mix atmosphere with charge in that rear portion, I'm sooo confident that if you modded the muff you'd have immediate results -- simply patch that hole on the top (I literally just patched over that entire area, sealing both my initial hole which was like yours + the OEM exit hole), then ~double the throughput of the holes in that central baffle, then place the new&only exit ports on the front of the muffler somewhere (I did about 65% exhaust flange for surface-area of exit port, split between (2) exit-ports that are ~1" apart so it has that nice dual-port 'pop pop' noise. YOU could test this out **w/o penalty** because you could un-do the plate on the top, and - on mine - I put my 2 front exits on that horizontal bar where the muffler-mount bolts go, so I could always use that fancy OEM plate to cover-up the holes if they didn't work well...but they did so I didn't touch anything, in fact I know my exit holes were "on the tight side" and my thinking was I'd enlarge-as-necessary but it's been so great I have no desire to touch anything, even my ugly 25.5thou squish I do not wish to machine-away because I don't want to change the timing and, w/ transfers in-mind, I've recently gotten the idea that, *usually* a gasket-delete's biggest impact (proportionately speaking) is *reduction* of that tiny transfers-open window, for instance on ms660 the crown BARELY hits the bottom of the upper-transfer, NOT fully though, so any gasket deletion is reducing transfer duration and IMO if you don't have a right angle grinder you've no business doing much of anything w/ the uppers of most saws! Thanks for posting all these vids man, have learned so much and am now doing a double-saw build it's awesome, and I'd NEVER have thought I'd be "working on engines" not even ~8 months ago, but I'd just gotten my cs590 and, seeing your vids, it seemed so easy to port it (you were *almost* done w/ your series, had *not* hit the problem yet though), anyway thanks because I'd never have attempted any of this (or my subsequent "two 660 clones" build, that I'm redoing/improving right now), wish you luck w/ this cs590 man, have felt so guilty because mine came out awesome simply because I'd asked for help online while copying your vids, so I deviated a bit from your approach, adding info from online & from instinct, but it came out well on porting #1, and *awesome* on porting #2 in fact I'm still running it pig-rich for longevity because there's simply zero need to add more power it can bury it's 20", even dull, into hard dead Oak and just keeps pulling-into the wood >;D
You guys our awesome.. I'm still so happy with the 590 rgt out of the box no adjustment. But I've only used my cs 310. I actually never thought I would need 2 saws. Now I want more lol.. run a lot of echo yard stuff always works when I call for it.. did you do a video on tuning a 590? after my 3rd tank I think I will do that and the little muffler mod.. I'm in the rabbit hole for saws lmao @ me
@@mercoldswfo I would not get that deep into this lol. I've a gas fireplace 🤣 Just have a saws ( 3 will be da max for me) for the house and I guess the little fire pit.
Tinman please read this. Long duration inlet timing is your problem, IMHO you don't have enough crankcase pressure. You know you only start building cylinder pressure once the exhaust port is closed ..... well you only start building crankcase pressure once the inlet port is closed. With a long inlet duration there are not many degrees to pressurise the crankcase charge before the transfer opens. Opening the transfer earlier as you propose will lower crankcase pressure further - that is going in the wrong direction. The fueling is too rich because the intake charge is coming out of the cylinder (and into the inlet) before the the piston closes the inlet port, intake charge travels back through the carb and picks up another dose of fuel and spits it into the airbox..... The already fuelled air is then sucked back in (again) getting yet more fuel. No wonder it is too rich. Closing the inket earlier fixes this too. JB weld that inlet port.....
Thanks for reply Tinman, don't know where that reply has gone, maybe its a private message thing, I'm not familiar with how the 'tube messaging works. But anyway, I just dont see how opening the transfers earlier is going to change the crankcase pressure when the piston is closing the inlet port. Sure, earlier transfer will reduce crankcase pressure sooner, trouble is inlet port has been closed xxx degrees by then. As you say, we'll see.
I agree his fix can't work to prevent spit back because the intake has long closed by the time the transfers open. The trouble is that he didn't touch the intake timing, except for the roughly 12 thou drop from base gasket delete, and that hardly seems like enough to all of a sudden cause mega intake spit back. I guess it's possible tho.
My echo Cs-400 was 114 on the exhaust opening and my intake duration was 135. It ended up at about 110 and 140 on intake duration. The interesting thing was that the exhaust port was offset to one side and very narrow. Also the transfers were stuffed under the bearings. So I didn’t really open them up just made them accessible so to speak. I widen the exhaust and polished. I added two “ notches” like what iron horse likes on the intake and roughed it up a bit. Seems to run pretty good.
I’d be tempted to remove all that material between the upper transfer’s… and widen my main a little… you need to keep the support material to stabilize the piston or I’d remove all that too! I’m completely at a loss unless I can actually see the relationships on a port map… I can’t visualize it mentally…😂😂😂😂. 45mm by 37.6mm!!! That’s a massive amount of stroke! That’s a lot of travel… ( A 1.6mm thick shim plate and a 50mm Stihl 044 topend … is that a 10mm or 12mm piston pin??? would definitely squeeze in there!!! Popping it up to the 70cc size…a little homemade popup would bump it even more… could make him a very special saw… I love the video that Joe Harkness or Dyno Joe put together… he did 4 or 5 different versions of this build… even tried to sleeve out around 56mm or something crazy like that but it wasn’t thick enough and it ate itself…. I’ve got to break down and get the little harbor lathe so I can make my own popup piston at home… I would definitely need to see those relationships on a paper page or a port mapping chart… I had a copy of the one that Kensie use’s but I lost the email… I have to try to have him send it to me again… his is better than mine…even though it’s just a chart with 360 degree’s on it… it’s an extremely interesting hobby for certain!!! 😂👍🤣🤣🤣
I am going to pull apart my Dolmar 7910. It will start and run for about 1 minute and quits and will not restart. Thought I might check the timing of the saw and open it up a little. Nothing crazy.....
G’day Marty. Have you checked the fuel tank breather? If it is blocked what you’re describing is a classic symptom. A way to see if it is the breather: after the saw stops running, take the fuel cap off and put it back on and run the saw again. If the saw restarts and cuts out again it is likely the fuel tank breather is blocked.
Another thing to check, are you losing spark? Sometimes as the ignition module warms it fails. Also try a new plug. How fresh is your fuel? It's always difficult to pin point the issue so you have to start eliminating potential issues. You may not know what it is but you start a list of what it isn't.
Or maybe put a carb on it that you think is just way to small and see what happens . Or use the same carb you have but put a restricter plate between the carb and the jug
Hey Tim man got a general question for you I have all steel chainsaws I want to buy some of that fuel line that you talk about Thai gone course that didn’t spell it correctly but you know what it is I need to know what sizes I should get for steel chainsaws and weedeaters and blowers I found a supplier It’s called H and L supply could you please let me know the sizes I need
Hey Tinman love the vids I just rebuilt a echo cs_4600 and rebuilt the carb but now I can’t get it to pop or anything and idea on what it could’ve be brand new ngk spark plug
None porting doesn't change bore or stroke now alot of times they big bore them example they take a 266 and put a 272 top end on and port it and call it a ported 266 hey look at my 266 cut bull shit it's a ported 272 butt I did hear bucken say that porting a saw makes it feel 5 cc bigger but I'm sure it varies
Ive got a CS590... All stock other than the muffler mod, I did the muffler mod the same way as you but a little less agressive with the grinder.. I did not make the hole as large as you... Stock carb and ignition.... Now I cannot get the saw to stop 4 stroking on top end... Even in the cut... High speed jet is as lean as it goes, yes I removed the little red limiters from the carb screws. The only way I can get it to stop 4 stroking in the cut is to force the saw through the cut, chain is brand new. Is this the limiter or is it too rich? Thanks!
There are comments addressing this on the other videos. The original carb has a bypass nozzle that won't let it lean out. If you replace the nozzle, it will lean out like a normal carb.
always look forward to seeing more on the CS-590, as someone who owns a stock one. once you sort out how to make it sing, you will have a lot of owners, like myself, who will want you to modify them.
I am glad he's getting back into this one. It has been in the shop for a while. Wondering what the solution will be.
For work we always used professional Stihls. I loved them, although starting them was always a temperament issue based on weather conditions. And personally, I don't like the choke on stihls. But for my personal saw, I purchased the Echo cs590 (based on cost) and it's been a great running little beast. I feel that they aren't refined like a Lexus, more like a Toyota Camry from the late 90's. You know, when you could work on them and afford one, and it lasted forever. Hope you get that beast working the way you want.
That’s a great perspective. I have some echo equipment, along with some stihl pro, and husqvarna xp. My echo leaf blower is just lean and apparently they did a better job hiding the screws. The 266 weedwacker punches above its weight. 26cc outdoes an 80’s 28cc echo and almost keeps up with a 32cc multi head JD (homelite?) it doesn’t have quite as much torque, but the ease of loading line makes up for it. I can still run low rpm and burp it for brush, or know it will spool up even in a hay field.
i dont know why everyone says stihls are hard to start. I never have issues getting mine started. Starts reliably cold or hot, regardless of how long its been since the last time it was run... if your saws arent starting easily, its not the saw, its your tune
I ported my cs440 per the tin man channel. It's only a 45cc saw. I put the exhaust at 103, intake at 71, and didn't touch the transfers at 127. The ends at 154 exhaust duration, 24 blowdown, and 142 intake duration. The saw runs great. About 11,000 rpm in the cut. Thanks alot Tinman. Maybe this will help.
Squish is about 31 thousands
What do these numbers mean? Trying to learn
Timing numbers. If you watch Tinmans cut a way series, he explains it really well.
Hope to see the 590 ripping soon Tinman. Charles Briscoe is doing some great work on these.
I think he raises the transfers too, and aims them at the intake. I also don't think he raises the exhaust roof as high as you did ... but you better ask him. His saws run awesome though!
So glad to finally get an update on the 590!
Love the build. One thing I always try to tell myself, if I fix a problem that I created, it’s still a win. I can’t wait to see you win! Stay warm tinman
My favorite part of your videos Tinman is the fact that you are not UA-camy. Just honest and straight forward love it!
Hello Tinman, I own a stock CS-590 and found your channel on a random search for my saw and now I'm hooked. You are my favorite saw nerd! I don't fully understand 2 stroke design but I love to listen to your porting and customizing theories. It's fascinating what you have learned from porting such a variety of saws. As you describe what you are seeing in the design of the 590 I wonder.....will the echo engineers talk to you? What happens if you pick up the phone and ask them about the things you are proposing?
Hey Tinman, you raised the exaust 10 deg to 104 . Squish is perfect, but with 10 deg less compressionstroke, you loose a lot static compression.
I think around 25 psi and that will be bad for torque and won’t make it zippy.
Base Cut or better a pop up could compensate the less compression issue
Maybee that is also part of the issue on that Saw. Kind Regards from Germany
Keep doing , you will get it rippin 👍
Bye
Keep the 590 video coming I've learned alot from these videos
Hi Tinman. Great video and quite informative. I have never ported a saw, but you make me want to try it. Stay safe and warm and keep these great videos coming.
Howdy Tinman! It’s been good weather here in northern Arizona. Some snow and ice, but 70F and sunny right now. Just picked up a cs590 Timberwolf based on your videos. Only planning to mod the deflector and adjust the carb for my homestead and farm saw needs.
AZ Highland, my cs590 took about 10 tanks to break in. Then it ran like a completely different beast. My suggestion is to just run it for a while before porting it or adjusting the carb right away.
@@SuperJamster1 thanks! I have two tanks through it already, so I’ll wait for a bunch more per your advice.
IMO you can't beat e'm for the price! Squish on mine was .041, base gasket delete yielded .029 . Did bg delete and muff mod before first full tank, tuned slightly rich and left it alone for a while. Mine woke up on the 8th tank. Then I made it an Ironhorse style pipe... WOW, what a difference! It feels like it gained 15+% power😃 has no problem pulling oregon exl on a 24" bar! Great farm/ranch duty saws, that respond well to simple mods.
@@SuperJamster1 thanks was thinking to do the same after the. 3rd tank.. thing is amazing otb why f it up.
@@bobbyslavo9722 Complete agreement. Although I'm a professional tinker. I'm retired now and for fun I work on 2 stroke engines, machines like 1970's mopeds, scooters, lawn equipment and of course, chainsaws. I've figured out a while ago, that "If it was a just a little faster" mentality never changes .
To confirm your suspicion a smaller carb should limit the charge in the crankcase and not exceed the limit of the transfer. It would be interesting to see if a small carb or restrictor plate would clean it up in the cut.
to me that seems a logical way to do it.
he did say he tried three different carbs, so hopefully one of them was a smaller one
@@waynegriswold8953 NO ,stock 590 slightley larger 620 echo and the big 80cc echo carb so not smaller than oe?
I've been running my new echo 590 for two months now and it was a good saw from day one but it hasn't done anything but get better and better all the time , I'm thinking about selling my Husqvarna 61 and buy another 590 !
Get the 620 if you sell
A Great learning experience for all. An amazing mechanic once told me his biggest advice is to be patient and humble. He told me that when you are stuck, step away and be patient. It's amazing how that works, but it does!
I for one, enjoy the weather updates👍 always been a little bit of a weather nerd. Good to see the CS-590 getting some more attention! Would be awesome if it woke right up with a little transfer port reshaping. Wouldn't be surprised if it does!
Nice to see the 590 back be nice to see what it does.
Glad to see the 590 back. Great information here. Always love seeing your videos.
Purchased CS590, runs completely like a pig. Throws gas everywhere, seriously Echo? Thank you for CS590 content.
Thank you for sharing all the tips and techniques. Nice to learn new things every time I check into the channel.
CS590 !! Your plan sounds great! Grab a grinder and go. Love those Echos.
The transfers in 590 echo is like a 305 with a quadrajet. No wonder she’s boggy 😆
The reason that echo has the secondary transfer as big as they do. Because of emissions notice how it is aimed at the exhaust. They want as much spent exhaust out as much as possible for emission standards. I would raise both transfers equally try 5 degrees first but try to aim the primary toward the intake.
Over a month of-20 C for coastal B.C. That’s like 40 below 78% humidity and wind . Now it’s raining all the metal roofs have slid off
Great advice as always thanx
Hey tinman here in Nova Scotia we are going from a plus two Celsius to a high tomorrow of minus thirteen Celsius with a windchill of minus twenty six Celsius. Gotta love them nor’easters. Your channel is very ensightful.
I love your thoughtfulness and understanding.
Hey Tinman sounds like your doing a lot of high end fiddling, all very interesting and starting to make more sense to me each time I watch a vid.
Been watchin since the XL76 build, first comment... One of your best vids on theory. 👍🏻 More drawings and think-through explanations please. Great, great vid!
Glad to see this back on the channel tinman
I think your right on this for sure...I think echo cut the transfers wrong probably by mistake...and let it ride.....I have one of these saws as well
Logic makes sense, draining the bottom end sooner should reduce pressure build up. Can wait to see it all come together. Excellent stuff once again. TC Tinman Mahalo 🤙🤙🤙... Tdawg.
You need to do a CS620p
Hay Tinman have you ever thought in changing the jets in the carb
Too big carb won't help that case loading issue either -- me thinks
You are a saw fanatic
Echoes kicked hard. Love it go till you're happy. I'll watch
Yay back to the cs-590 very excited this build ! Stay warm tin man!
I really want to see this saw back together and ripping.
Thanks Tinman. We are allways learning time to try something else. That's half the fun doing a build see how it runs.
Great explanation. Hopefully you are right and make that saw a lil beast!
Sounds like a good plan Tinman. In the other videos for this saw it seemed tied up and not running free. I think you have it. Good luck with it. We will be watching. Thanks
Tinman, what about lessening the overall intake timing and running a smaller carb, but not making any other changes? From your explanation, it seems as though keeping longer blowdown would increase dynamic compression, thereby increasing performance.
Carbs are generally oversized, but if it’s right sized it still doesn’t restrict flow until WOT. I just bought one for a stihl, ms 210,230,250 all use the same one. 4-stroke kohlers are the same 12,14,16hp all use the same carb.
Thanks for the update 10 man really sounds like you're on the right track looking forward to the outcome keep the videos coming love the content
Cool, was waiting for you to tear back into this one.
So damn fascinating watching this, thanks for posting these Tinman!! The echo transfers are insane, I'm happy working on 660 transfers but wouldn't dare touch my 590's uppers!! Have you studied the 7310's uppers yet, where the secondary is so wide they had to bridge the port? Crazy awesome!! My understanding is that the 2 transfer channels are achieving different things, IE the primary is "helping finish exhaust-expulsion" while the secondary is "refilling the chamber for the next stroke", so far as I understand it after reading Jennings "2 stroke handbook"! Still fascinated and honestly I suspect a LOT of the final transfer design of a saw like these echo's is done in more of a 'trial&error on the flow-bench" approach, than in a mathematically-derived approach (would love your theories/thoughts on this!)
Re Velocity...dogging-out the lowers will certainly achieve higher velocity of charge-dispersement so that may not be helping you (though mine are dogged at least as much as yours..though I didn't even look at the uppers(you'd said not to, in the videos ;D ))
In Jennings' book he makes a point to keep bringing up velocity but it seems like it's pretty strictly / normally a thing relating to loop-scavenging, though of course the extremes of anything here will result in "short circuiting"/carb spitback/excessive loss of charge through muffler.
"Widening the intake will reduce [potential]velocity of the intake-tract, therefore reducing case-pressure" I'm not positive this is right, I defer to you of course but I think that's inaccurate, here's why: While velocity can indeed be changed by port-shaping, widening wouldn't "reduce crankcase-fill" because *that* is a *direct* correlate of the unswept(swept?)volume of the jug that MUST be moved for the piston to move & comply w/ physics.....put in your analogy, "The syringe will still dispense 30CC if you depress the plunger that much, regardless of width of the syringe or the girth of its needle", because depressing 30cc from it FORCES this. MY understanding was that this is how the 2-stroke jug functions insofar as "flow volumes", and that BOTH velocity & turbulence are very VERY much secondary-considerations, not unimportant by any means but not remotely as-important as displacement//rpm, but far more important for the "loop scavenging effect" that drives our lil 2-strokes, in fact if I'm reading Jennings' book correctly then your idea of "widen the intake port in this instance" would actually HURT you, because as you get to higher RPM the total-throughput of your wider/larger intake port will be of GREATER significance than any velocity attributes could ever effect (if that's even what the intake-velocity reduction achieved, as I understand it a velocity reduction would be for efficiency of loop-scavenging IE less intake going-out the exhaust port, since a given volume IS gonna come out of that intake *based-upon* piston-displacement during the stroke, and our battle always seems to be "keeping it in the jug" especially if the muffler isn't on-point which sadly I'd say applies to MOST powersaw-tuners' mufflers :/ Had actually discussed this case when I had the good fortune to speak with Kensie and I was surprised he didn't agree (didn't disagree either, I don't think, but certainly didn't come across like he thought it had much validity) that this is a problem of muffler.....you still have a big hole in your rear-portion of the muffler, automatically making your saw mix atmosphere with charge in that rear portion, I'm sooo confident that if you modded the muff you'd have immediate results -- simply patch that hole on the top (I literally just patched over that entire area, sealing both my initial hole which was like yours + the OEM exit hole), then ~double the throughput of the holes in that central baffle, then place the new&only exit ports on the front of the muffler somewhere (I did about 65% exhaust flange for surface-area of exit port, split between (2) exit-ports that are ~1" apart so it has that nice dual-port 'pop pop' noise. YOU could test this out **w/o penalty** because you could un-do the plate on the top, and - on mine - I put my 2 front exits on that horizontal bar where the muffler-mount bolts go, so I could always use that fancy OEM plate to cover-up the holes if they didn't work well...but they did so I didn't touch anything, in fact I know my exit holes were "on the tight side" and my thinking was I'd enlarge-as-necessary but it's been so great I have no desire to touch anything, even my ugly 25.5thou squish I do not wish to machine-away because I don't want to change the timing and, w/ transfers in-mind, I've recently gotten the idea that, *usually* a gasket-delete's biggest impact (proportionately speaking) is *reduction* of that tiny transfers-open window, for instance on ms660 the crown BARELY hits the bottom of the upper-transfer, NOT fully though, so any gasket deletion is reducing transfer duration and IMO if you don't have a right angle grinder you've no business doing much of anything w/ the uppers of most saws!
Thanks for posting all these vids man, have learned so much and am now doing a double-saw build it's awesome, and I'd NEVER have thought I'd be "working on engines" not even ~8 months ago, but I'd just gotten my cs590 and, seeing your vids, it seemed so easy to port it (you were *almost* done w/ your series, had *not* hit the problem yet though), anyway thanks because I'd never have attempted any of this (or my subsequent "two 660 clones" build, that I'm redoing/improving right now), wish you luck w/ this cs590 man, have felt so guilty because mine came out awesome simply because I'd asked for help online while copying your vids, so I deviated a bit from your approach, adding info from online & from instinct, but it came out well on porting #1, and *awesome* on porting #2 in fact I'm still running it pig-rich for longevity because there's simply zero need to add more power it can bury it's 20", even dull, into hard dead Oak and just keeps pulling-into the wood >;D
Is it a pre-ignition detonation issue? Maybe try the base gasket again.
Swap the main nozzle out in the carb if you have not already. It has a bypass and you need a nozzle without one.
You guys our awesome.. I'm still so happy with the 590 rgt out of the box no adjustment. But I've only used my cs 310. I actually never thought I would need 2 saws. Now I want more lol.. run a lot of echo yard stuff always works when I call for it.. did you do a video on tuning a 590? after my 3rd tank I think I will do that and the little muffler mod.. I'm in the rabbit hole for saws lmao @ me
I lost count at 30, i don’t think it ever stops. Consider yourself warned haha
@@mercoldswfo I would not get that deep into this lol. I've a gas fireplace 🤣 Just have a saws ( 3 will be da max for me) for the house and I guess the little fire pit.
Tinman please read this. Long duration inlet timing is your problem, IMHO you don't have enough crankcase pressure. You know you only start building cylinder pressure once the exhaust port is closed ..... well you only start building crankcase pressure once the inlet port is closed. With a long inlet duration there are not many degrees to pressurise the crankcase charge before the transfer opens. Opening the transfer earlier as you propose will lower crankcase pressure further - that is going in the wrong direction.
The fueling is too rich because the intake charge is coming out of the cylinder (and into the inlet) before the the piston closes the inlet port, intake charge travels back through the carb and picks up another dose of fuel and spits it into the airbox..... The already fuelled air is then sucked back in (again) getting yet more fuel. No wonder it is too rich. Closing the inket earlier fixes this too.
JB weld that inlet port.....
Thanks for reply Tinman, don't know where that reply has gone, maybe its a private message thing, I'm not familiar with how the 'tube messaging works.
But anyway, I just dont see how opening the transfers earlier is going to change the crankcase pressure when the piston is closing the inlet port. Sure, earlier transfer will reduce crankcase pressure sooner, trouble is inlet port has been closed xxx degrees by then. As you say, we'll see.
I agree his fix can't work to prevent spit back because the intake has long closed by the time the transfers open. The trouble is that he didn't touch the intake timing, except for the roughly 12 thou drop from base gasket delete, and that hardly seems like enough to all of a sudden cause mega intake spit back. I guess it's possible tho.
maybe echo did the transfer ports like that with a restricted muffler to get the saws through EPA regulations?
That is my thought. It's all about emissions.
Both the Walbro 590 and 620 carbs have the h-jet that are governed and you can’t tune.
My echo Cs-400 was 114 on the exhaust opening and my intake duration was 135. It ended up at about 110 and 140 on intake duration. The interesting thing was that the exhaust port was offset to one side and very narrow. Also the transfers were stuffed under the bearings. So I didn’t really open them up just made them accessible so to speak. I widen the exhaust and polished. I added two “ notches” like what iron horse likes on the intake and roughed it up a bit. Seems to run pretty good.
I bought a new cs 620 pw , so the timing of this video is perfect!
Learned a lot, as usual. Keep em coming Tinman!
I’d be tempted to remove all that material between the upper transfer’s… and widen my main a little… you need to keep the support material to stabilize the piston or I’d remove all that too! I’m completely at a loss unless I can actually see the relationships on a port map… I can’t visualize it mentally…😂😂😂😂. 45mm by 37.6mm!!! That’s a massive amount of stroke! That’s a lot of travel…
( A 1.6mm thick shim plate and a 50mm Stihl 044 topend … is that a 10mm or 12mm piston pin??? would definitely squeeze in there!!! Popping it up to the 70cc size…a little homemade popup would bump it even more… could make him a very special saw… I love the video that Joe Harkness or Dyno Joe put together… he did 4 or 5 different versions of this build… even tried to sleeve out around 56mm or something crazy like that but it wasn’t thick enough and it ate itself…. I’ve got to break down and get the little harbor lathe so I can make my own popup piston at home…
I would definitely need to see those relationships on a paper page or a port mapping chart… I had a copy of the one that Kensie use’s but I lost the email… I have to try to have him send it to me again… his is better than mine…even though it’s just a chart with 360 degree’s on it… it’s an extremely interesting hobby for certain!!! 😂👍🤣🤣🤣
that added or made me realise alot better the workings of a two stroke nice
I have two 590's for farm firewood think I might do the ignition,carb and muffler mod and call them good
Thanks for the update and explanation Tinman. Take care.
This video was so mich information… it eas very very good video. Inlove your videos!
What you said at the end is totally how I am too
Great teacher! New piece of the Puzzle.
LOVE YOUR EXPLAINATION ,,HOPE YOUR PLAN WORKS TAKE ER EASY TINMAN ,,
Before you make cuts you can not undo how about trying taking away some intake timing with the jb/ liquid metal ?
I've bein holding off on porting mine because of all the horror stories of bad running, overly right builds. Can't wait to see what happens
Nice to have a fire , I freeze every time I watch your videos. lol
Thanks for this video I am thinking about doing this to my saw
Have you talked with Charles Brisco on UA-cam? He's even having great success on these echo saws
Seems like they’re trying to keep the fresh air and fuel close to the intake port with that transfer design.
Tinman. I'd love for you to do a 50cc saw
The return of the cs590 saweeeet
HEY tinman I don't know about you I,M ready for spring time buddy 😉😄 tired 😴 of the cold weather got plenty of chainsaw work to do OMG 2 2 2022
It’s interesting that it ran ok initially. Why do you think that happened Tinman?
Could be trying to put some welding on the intake to make it 150-ish a good operation?
Im still whaiting for the homelite xl 922
Buddy if you grind through ur transfer shipper to NC USA and ull get it back free and like servepro baby, like it never even happen
That’s a very generous offer.
Good onya mate! Should be more peeps like you and the world would be a happier place.
@@brendanthebattlerstafford5145 it's a passion. Not work lol, and take just a few minutes
Cold to me is 40s, and it's been COOOOLD HERE TOO, 40F that is lol
Yep lol. Anything below 55F in the shop, fire up a heater. Below 40, load up the wood stove!
Well explained.
Holler at dynojoe he has these echos figured out
Nice vid TIN MAN Thanks!!!
Did .006" of piston travel equal 1 degree on this saw? Perhaps you mentioned it in a previous video video and I missed it.
I am going to pull apart my Dolmar 7910. It will start and run for about 1 minute and quits and will not restart.
Thought I might check the timing of the saw and open it up a little. Nothing crazy.....
G’day Marty.
Have you checked the fuel tank breather?
If it is blocked what you’re describing is a classic symptom.
A way to see if it is the breather: after the saw stops running, take the fuel cap off and put it back on and run the saw again.
If the saw restarts and cuts out again it is likely the fuel tank breather is blocked.
Another thing to check, are you losing spark? Sometimes as the ignition module warms it fails. Also try a new plug. How fresh is your fuel? It's always difficult to pin point the issue so you have to start eliminating potential issues. You may not know what it is but you start a list of what it isn't.
Is the cylinder on a 590 the same as a 620p, I know the piston on a 620 has two rings compared to a single ring on a 590
Great info as always.👍
Or maybe put a carb on it that you think is just way to small and see what happens . Or use the same carb you have but put a restricter plate between the carb and the jug
do you have any suggestion on how to spicy up an old Stihl 023?
Great explanation..
Could you do some finger ports to help it?
Hey Tim man got a general question for you I have all steel chainsaws I want to buy some of that fuel line that you talk about Thai gone course that didn’t spell it correctly but you know what it is I need to know what sizes I should get for steel chainsaws and weedeaters and blowers I found a supplier It’s called H and L supply could you please let me know the sizes I need
Hey Tinman love the vids I just rebuilt a echo cs_4600 and rebuilt the carb but now I can’t get it to pop or anything and idea on what it could’ve be brand new ngk spark plug
Ngk always gave me trouble over the years there highly over rated, had the the best luck with plain old cheap champion
Do you have any recommendations for a quality aftermarket cylinder/piston for a Stihl 193t?
Have you thought about porting a 041 sthil
I've seen never seen single digits here eastern nc in 30years
anybody know the difference between the cs-590 and cs-600?
Have you thought about putting a reed on it 🤔 ? I'm no pro by any means but I feel like a reed might solve your problem
Try try and try again that’s how we learn
Thank s!!
Why is there two holes on head or top sqish of cylinder on echo decomp ?
Yep, spark plug and decomp.
They do it because of a 5 year warranty
Hay tinman how much cc do you Gan when you port a saw
None porting doesn't change bore or stroke now alot of times they big bore them example they take a 266 and put a 272 top end on and port it and call it a ported 266 hey look at my 266 cut bull shit it's a ported 272 butt I did hear bucken say that porting a saw makes it feel 5 cc bigger but I'm sure it varies
Ok thanks Tinman have you ever thought of changing out the jet size and have you ever balanced and blueprint a chainsaw
Is there a way to contact via Facebook?
Ive got a CS590... All stock other than the muffler mod, I did the muffler mod the same way as you but a little less agressive with the grinder.. I did not make the hole as large as you... Stock carb and ignition.... Now I cannot get the saw to stop 4 stroking on top end... Even in the cut... High speed jet is as lean as it goes, yes I removed the little red limiters from the carb screws. The only way I can get it to stop 4 stroking in the cut is to force the saw through the cut, chain is brand new. Is this the limiter or is it too rich? Thanks!
There are comments addressing this on the other videos. The original carb has a bypass nozzle that won't let it lean out. If you replace the nozzle, it will lean out like a normal carb.
@@telecasterfool1773 Interesting, Ill try to find what you are referencing... Thanks!
@@aj06bolt12r let me know if you don't see it...