Newbie Intro (and possible CS 300/340/3400 rebuild help request) Thread

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Gamma Woods

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Hi, I've spent too many decades running walmart-special style 30ish-CCs and felt it was time to get a big-boy saw. I mostly cut for firewood, clearing trails and the occasional removal, but wanted to spend a bit more and have something worth holding on to for more than a few years. Something worth taking care of, something I would enjoy running. After months of lurking this site (and OPE forums, and FF, and arbtalk... and some of the less annoying faces on youtube) I felt even a small big-boy saw would be worlds above and settled for a 261 c-m. Of course the dealer has nothing but a handful of homeowner saws left in stock, so went over to those fellows in orange and grabbed a 550 mk 2 instead. Love it. Love it so much I went back and grabbed a 16 inch bar and ordered a 20 inch Sugihara. I stopped thinking about using the saw to do what needs to be done, and started thinking about what I can use the saw to do. Heck, I started finding things that didn't need to be done just to get an excuse to run it. But I started to think of tasks I might one day possibly have a slight chance of wanting to do, tasks I need a new toy for. And of course stalking you bastards blew the CAD to full proportion. Is it still CAD if it also extends to things like the 535FBX and brush-cutters?

I grabbed a box of old busted Echos today, some will need more work than others, definitely going to order 4 carbs tonight but have yet to do a full inventory. I've heard they don't pack much of a punch, but want to tinker and have a deep seeded hatred for my Poulan 2050 so that's not getting any of my newfound interest. So anyways, hello!
 
So I got those 6 incomplete saws, some are missing carbs, most have broken purge bulbs, only a single air filter and air filter cover, 2 of them are missing the starter assembly and there aren't enough handlebars to go around. I decided to do some testing to see what works and what doesn't. Testing spark is the first thing, I got spark from 3, the 4th had a broken boot, and 2 didn't have the starter assembly/pull cord. I took the assembly off the one with the ****ed boot, tested the next saw with that assembly and got spark. I moved the assembly to the final saw, it had spark but was very stiff and hard to pull. I lubed and loosened up a bit to where I wanted to see how it would feel to drop-start. The ****ing thing fired up. It had old gas from the guy who sold them. This was the oldest saw (cs-300) amongst the lot, it was the dirtiest and it was missing a chain brake, handlebar, starter assembly, air filter/filter cover and the clutch cover.

Something weird I noticed when pulling but didn't really click in, was that the clutch would move when I pulled. After I got the saw started and cleaned it out, put some fresh fuel in and loaded BC, I noticed the chain would move while idle. If I tried to move the chain with my hands the engine would turn. I popped the clutch off and sure enough the needle bearing/sprocket bearing was rusted and stiff. I popped one off another machine, put it on and it works. It runs nicely, doesn't like to idle when it's first started or after a big cut, doesn't have too much power and the chain speed seems low. But I don't think most of these saws have been run in ages, and some of the cylinders and pistons seemed pretty nasty. But I was enjoying the high of the success and wanted to burn some fuel before thinking of scrubbing it out.

It's very good on gas, I only gave it 1/3 of a tank (the tank only holds a cup) and probably had it running 30 minutes, cutting for 10 and it didn't seem to drain much at all. Something ****y is going on with the oiler but that's something to worry about after I finish with the engine. I did another 15 minutes of hard cutting before adding some seafoam.

I may have had too little gas and too much seafoam because it really didn't want to run, just for a few seconds at a time, which is fine because it's still getting that seafoam where it needs to be. Waited an hour, couldn't get the saw started at all except for 2 seconds one time. Put half a tank of gas in, mixed it around and saw fired right up. It was dark so I couldn't tell if the big plumes coming out were made of steam or if it was nice nasty dirty chunky smoke. Ran it for a few minutes, giving it full throttle from time to time, and killed it by choking. I filled up the rest of the tank but I probably shouldn't have, might've been smarter to just run it at that high strength half tank, and left it overnight. Ran it a bit the next day, not too much smoke. A bit piggish to get started at first but I kind of expected that, and couldn't go WOT for more than 3 seconds in a cut, I had to pump it a bit. I've been holding off on tuning until I get some replacement filters and get everything cleaned out (and the seafoam mix pushed through) but seems a bit lean. It will idle for days.

It didn't seem to be oiling the bar, just the tail (after several cleanings), I should've checked the oiler before... the foam piece was clogging the output so I pulled it out and wrung it out a little, it was actually folded and wadded up a bit. Seems to work fine now. Yanked the spark plug and it's still pretty bad in there, a dip of the rag managed to remove a fair amount but looks like there's a lot caked. Dropped some straight Seafoam into the chamber and I'll give it a rub tomorrow. I have to grab some gasket material before I think about opening it up to clean (might be good to have a ring handy too).

I have some parts coming but decided to work on another one that's almost complete, just missing air filter and cover and purge bulb. It looked like he bypassed the purge, so I figured it would be fine but I just couldn't get it to turn over. I grabbed the purge bulb from another saw, and while taking the broken one off I noticed that the bypass job the guy did pinched a fuel line closed. New purge bulb works, but the carb pisses gas out a busted seal. The saw runs on full choke, though! I've got 3 chinese carbs coming and an OEM carb repair kit on it's way, but there's still 1 other saw that's got a carb on it (6 saws - 3 carbs) so if I get impatient I might move it over. Or try working on that saw tomorrow!

The chain breaks, handlebars and starters are too bloody expensive to get to Canada, but I've got enough mis-matched chain-brakes to go around (though model differences will leave the muffler exposed on some but that's not insurmountable) and might just fabricate the handlebar or some mounts for other starters (if that's possible?). I've definitely fallen down the rabbit hole.
 
The cs300 (the one I've got running) managed to get relatively clean, and cut really nicely with a new cheapo Oregon 12 incher B&C bundle. Took a little bit of tuning (and some more cleaning when I realized how much crap gets sucked in if you don't plug the adjustment access port) and actually needs a bit more tuning, but I noticed something neat when running it as the sun starts to fade.


I also noticed that it takes quite a while to idle down, and RPMs drop when I move the saw to different angles, which my inexperienced mind thinks would be related to that leak. As I was already planning on getting some liquid gasket, I think I'll try a cheap sav-a-thread fix. That will give me enough reason to crack it, clean up the P/C, likely replace the rings and some bearings (hopefully not a jug). Might do a break cleaner test tomorrow to see if there are any other leaks (besides the grommet for the oil tank which is being ignored for now) to give me an idea if I should wait for even MORE parts before cracking it (though it wouldn't be wise to order something before knowing if I need it or not). Going to be a few more days before I make it in to town to pick everything already waiting for me. I really don't have much in the way of testing equipment and have yet to gain the ear or the touch so I'm going to need the crutches of a compression tester and a tach until I earn the experience.

Think I'll move on to the carb repair on the next unit (cs-340) before pulling apart the cs300's cylinder, just in case a series of highly unlikely, life or death situations arise where I need a running top handle. Or I just want to watch the shiny lights dance. Speaking of dancing, I never noticed how cheap USC' are....

Here's some sounds, I love how easily she starts (though she was idling for a minute while I took the pictures before turning her off and recording audio). At about 45 seconds I put her into some wood, sounds a bit fat. When I pull out, around 1 minute in, she seems to be idling pretty high, 10 seconds later I rolled her onto her side, clutch side facing the sky, and notice how her song shifts. I twist her back upright, then back to her side for a few seconds, eventually putting tooth to wood again. I think it sounds a bit cleaner for the next bit, but around 2:15 I take it out of the cut then give it 2 small blips and you can hear it takes about 10 seconds for it to idle back down, then seems to rev down and up for a little bit. Am I right in thinking a leak (such as my spark plug/disco ball) is a likely culprit for the behaviour?

 
Looks like a bad plug with a leak around the porcelain
That could be, I'll swap another one over. I thought this one "looked" the best, and gave the best spark, but it was absent-minded of me not to try another one before assuming the previous owner/s damaged the cylinder threads. Probably be wise to clean all the plugs and check gaps while I'm at it, I guess my order-of-operations needs refining.
 
It's a lot of fun taking a basket case to running......good job!. I've got four little old Echos that I picked up and refurbed just the way you did, and won't part with any...they are what I go to when cutting brush and saplings.
 

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