My Tractor Forum banner

Bought a "new" Echo weed whacker

12K views 14 replies 6 participants last post by  RedOctobyr 
#1 ·
I'd been looking to find a replacement for my old & cheap curved-shaft weed whacker. I picked up an Echo SRM-2100 (straight shaft) tonight off Craigslist for $30. It wouldn't start (owner said it ran last year), but I checked the compression before buying it, and got 150 psi. It looks to be in good condition otherwise.

Got it home, confirmed it had spark. Figured out which direction turns the choke on (the label for the choke lever is gone), squirted a bit of gas in the spark plug hole, and gave it it a pull. It fired right up :) It will run fine with the choke set just right (almost-fully on). Turn the choke off, and it dies. Turn it on fully, and it will falter & run rich (or stall). The Hi mixture screw is out as far as the adjustment caps allow.

So I think it will need a carb cleaning/rebuild. But hopefully that will get it back in good shape. It is S/N 812xxx, so, per the parts manual, it has Zama carb C1U-K52. It looks like the diaphragm/rebuild kit is Echo 12530013310. I'm hoping I can turn it into a nice, reliable machine.
 
#3 ·
I've got that model. Mine has the easy start ( I get out of breath if i have to yank really hard ) and I really like it. Also have the brush blade to cut back the forsythias etc. when they start to encroach on the yard. Nice little machine. You got a heck of a deal.
 
#4 · (Edited)
Thanks guys. I did some calling around today, and was unable to buy a rebuild kit locally. Had some time, so figured I would just try carefully disassembling it, and cleaning the carb. Fortunately, no gaskets ripped or anything :)

I took the carb apart, sprayed carb cleaner through everything, including the adjustment screw holes. Cleaned off the adjustment needle tips. I did not run wires through passages, just sprayed things out, and watched for the spray to come out somewhere else. The Low/High screws had the emissions caps on them, so I had to "modify" those before I could remove the screws. Unfortunately, my modifications made it so the cap on one screw started to slip, as I was screwing it in, to count the factory turns. So I lost track of the initial settings :rolleyes:

I did have a bit of a problem with the primer, one or both of the checkvalves started having trouble after I sprayed cleaner into it. It would not actually move any air, the bulb was just sealed shut, even with that assembly removed from the carb. Gently poked a copper wire into each valve until they started working again, then reinstalled it. Once it got some gas through it, the primer appeared to work properly again.

It fired right up, though I had to spend some time fooling with the Low/High screws to try to get it running properly at idle and WOT. I think it's running OK, but I'll get a better sense the first time I really try to use it. I tried to adjust WOT to the 9,500-11,000 in the manual, but in leaning out the High end, the RPM's started to drop again once I got to about 9,000. I left it set around 8,500. I did not think to check the muffler and spark arrester screen, to see if they are plugged.

If I didn't have a tach & RPM specs, I'd have said it's running fine. Might play with a bit more to see if I can reach the manual's RPM's, without seeming like I've gone too lean, just because that makes me wonder if something is still wrong. Seems like a nice machine, should be powerful enough for what I need, and it's pretty light. Definitely a big improvement over my old one!
 
#5 ·
Did you also change the little gas filter down in the tank?

BTW__I have the same unit, and other than a spinning head problem with some bad string--everything on it is good to go!

glenn
 
#6 ·
I did not. But the previous owner said he'd just replaced it. I can check it, to make sure. The air filter is not new, but it looks to be pretty clean.
 
#7 ·
That little adjustment you made to the needles--if you completely remove what's left,they normally have some kurnning on the head that you can grip w/finger or pair of needle nose.:trink40: Echo has good stuff,I got a hand held blower-one of my most used tools.
 
#8 ·
Sorry, the post was getting long enough as it was, so I didn't elaborate.

I put a slice up the side of the cap which ended up slipping, while trying to get it off. It still didn't want to come off, so then I cut off the "ears", so it was just a smooth cylinder, and could rotate 360 deg. I only cut off the ears of cap #2. Unfortunately, the slit up the side of cap #1 let it start to slip on the knurled head, so I ended up ripping it off entirely.

Under the cap, I found a flat-screwdriver head. So I didn't have to try and Dremel a groove in it :thThumbsU

If anyone knows the factory # of turns out for the EPA adjustment screws, I'd welcome that info, at least to compare against my settings :thanku:
 
#10 ·
Thanks redmule, that was a big help :thanku:

Yesterday's settings turned out to be around 1 1/8 turns on both Low and High.

I checked the spark plug gap (good, is supposed to be 0.026", is just over 0.025", and under 0.030"). The fuel filter looks new. Pulled the muffler off and checked the spark arrestor screen. The screen looked good. Burned it off with a lighter, and went over it with a brass brush to clean it up. The muffler port was clean. The cylinder bore and piston look good, no scoring.

After going through the adjustments again, I actually ended up right around 1 turn Low, and 1 1/4 High. Which is also reassuring, since it means the carb isn't still half-plugged, if it runs OK with the factory settings. It's idling well. A WOT, once warmed up, it's now around 9400-9500 RPM. I could try for more, but I have no interest in burning anything up.

I have it a bit more lean than yesterday. Yesterday it would border on 4-stroking at WOT. It's smoother, with less smoke, now. My main point of comparison is tuning my old Stihl chainsaw, which I have tuned to 4-stroke at WOT, but it will smooth out with a load, in a cut. My tach doesn't go high enough to tune the saw by RPM (tach maxes out at 9,999), but it works for when I'm trying to do here.

I'm happy with how it's running. I will probably try to replace the 3-port gasket in the tank, and the fuel lines, which run through it. That gasket is very cracked, and the lines are old.
 
#12 ·
That's a good tip, thanks. I had not realized that. Fortunately, even blind squirrels occasionally find a nut. After I'd posted, I was looking on eBay for tank gaskets, and stumbled across those fuel line & gasket kits. Those are a good deal.

Fuel tubing seems rather expensive to buy locally by the foot, so getting the proper sizes & length is nice, plus the gasket. Some kits have a fuel filter & air filter. Kudos to Echo for making it easy like that. You can see the models that a kit will work for, what it includes, and the prices are even quite reasonable.

Found a gasket & line kit that also includes a fuel filter, tank venting valve, and the extra line that goes to the vent. I probably would have added more cost trying to buy a short piece of tubing to replace the vent line myself, so I bought the kit with everything. It doesn't list my model in the compatibility list, just the newer SRM-210. But it *looks* right. And if the tank vent is the wrong one, or whatever, I just won't install that piece. What I really need is the gasket and lines.

I'm hoping the new gasket & lines will make it easier to prime. Currently, I have to pump it a lot before gas actually starts to move. My guess is the cracked gasket is letting the air pressure leak out of the tank, rather than pressurizing and forcing gas through the lines.
 
#13 · (Edited)
Replaced the tank gasket and lines today. Took it out to test it, and decided I'm not quite out of the woods yet. It started nicely, but wouldn't rev up properly. It would be fine until maybe 1/2 throttle, then if you went beyond that, it would just die. Kept doing it, and I started playing with the High needle, since my guess was the High jet wasn't flow any/enough gas. Turned the High screw out quite a bit (2-2 1/4 turns), and suddenly it was running well.

It did this to me once or twice last week, while tuning. Seemed to be brought on by fooling with the needles. Example, screw it all the way in to count the turns, then back out to the original setting, and suddenly it would die with throttle.

Did a bunch of trimming. Most of the time it ran great. Then a few times it would, at random, do the same thing. Too much throttle, and it would just die. Revved it a few times, and waited a bit, but made no needle adjustments, and then it was OK again.

Finished, and checked the RPM's. It was now up to 9700-9900, and unscrewing the High needle didn't do much to lower the RPM's or add smoke.

Can you have a sporadic blockage of a jet/needle? I removed the High needle, the tip looks good, I sprayed some carb cleaner into the hole. Tried again, no real improvement. It will sound good, but you can unscrew the High to 3 turns, and nothing really changes.

So I am guessing I must have something stuck in the High channels. Will have to take the carb apart again and look for something that might be clogging it. Any other things I should check for? Thanks.
 
#14 · (Edited)
Took the carb apart. Found two issues, I think.

1) The main nozzle/checkvalve seems like it's plugged. With the the fuel pump diaphragm and cover removed, there is a small hole visible, which connect to the High needle.

With the High needle removed, carb spray comes out the High hole. But the Zama technical guide says that, with the High needle out 2 turns, you should be able to manually blow through the hole, but should not be able to suck air through it. I put a tube up against it, but I can't blow or suck any air through that hole, with the High needle out 2+ turns.

I think the nozzle is clogged somehow. Unfortunately, it's brass, and pressed-in. The manual says to "carefully" drive it out, only if needed. Not sure how you drive it out from the inside of the carb, you can't reach it very well :) I have some Chemtool B12 (the most "effective" stuff I have, along with spray cleaner), I could soak that portion of the carb in that, and see if it helps at all.

It is strange that *sometimes* it runs fine. And other times it simply will not rev up at all, and just dies when you add throttle, acting like something is plugged. I don't really understand why it would be intermittent.

2) The primer is still having trouble. I think one of the checkvalves in it has a problem. You have to pump and pump and pump before some gas might finally make it through the carb & primer bulb. Once some gets to the bulb, when you pump it, you see the gas just go towards the tank, and then pulls back *from* the tank, through the same clear line. It's just moving back & forth, not pumping in a single direction. There's a welch plug covering the checkvalve that I think is messed up, but the old carb kit I have handy does not have one of those plugs, so I don't want to remove it.

Is there a way to clean these? The nozzle is the more essential one to get sorted out. And a new carb is fairly expensive, at least vs things like rebuild kits, at $40+. Thanks.
 
#15 ·
Just wanted to post an update on this.

After doing a bit more reading, you're not supposed to use aggressive cleaners on the main nozzle/checkvalve. I'd previously sprayed carb cleaner in it, so wondered if I could do anything to help it. It appears to be sticking intermittently. When I took the carb apart again, I found that now I *could* blow through the nozzle, but still could not suck air through it (which meant it was working properly). I decided to try and see if I could loosen it up a bit, so I poured some bottled Liquid Wrench onto the hole that feeds the nozzle. Let it run in, then also blew through the hole, to work it in.

I did the same thing to the primer base. If I damaged the checkvalves with carb cleaner, maybe putting something else on them could help. So poured a bunch of Liquid Wrench through that as well, and sucked it through the 2 valves.

I picked LW vs something like motor oil since it's so thin, and would do a better job of wicking its way through the parts.

I let them sit overnight, then wiped off the excess and re-assembled. The primer is working better (not perfectly, but at least it works), and the engine has run fine so far. It needs to warm up for a minute or so before it revs smoothly. The choke setup is a bit odd, it really only has On and Off positions, there isn't really a half-choke position for warming up.

But I've started it up on 5-6 different days, to test it, and it started & ran fine each time. Did some trimming with it yesterday, no problems. No issues with it suddenly dying when throttle is applied, so I think the nozzle/checkvalve is working better. If that does give me problems again, it's about $5 to replace, not a big deal.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top