Echo ES-250

[plpitts1]

Hello, I have an Echo blower ES-250, Serial P41814139809. Will start right up but only chugs heavily along, chugs harder when I squeeze the trigger. Seems to run rich, spark plug gets soaked and muffler gets wet but keeps on chugging. Compression is 140, removed muffler and screen, they are clear (ran for a couple seconds without muffler to make sure, ran the same) Had an extra new carb so tried that along with new plug, made no differance. Help please.
Thanks,
Pat

[KE4AVB]

I would assume that the carburetor needs tuning. Yes the Zama RB-K106 has been both a low speed and high speed mixture adjustments. But before even making these adjustments you need to make sure that the metering lever is set correctly. As if it is set high it will cause flooding or over rich condition that you describing.

[plpitts1]

Thanks KE4AVB, did not think of the Metering Lever, I will check that. I have never had any problems with a new carb from Echo. Will let you know, hopefully get back to that one today.
Thanks again,
Pat

[Skywatcher]

Hi PLP

If the unit behaves the same with a brand new OEM carburetor, I'd be inclined to start looking elsewhere. To me, your description of chugging heavily almost sounds like retarded ignition timing. Check the flywheel to make sure the cast-in key has not sheared allowing the flywheel to slip back on the crankshaft. Also make sure the flywheel nut is actually holding the flywheel in place and not bottoming out on the threads.

I had one Homelite chainsaw that almost drove me crazy back in my early years of being in business. The unit would start just fine and idle nicely, but when the throttle trigger was squeezed, the engine would labor hard and overheat. What had happened is the flywheel nut had bottomed out on the threads, so was not holding the flywheel tight onto the taper. The flywheel key had worn the slot in the flywheel so when the starter cord was pulled, the flywheel would slip forward putting the engine in time to start. As soo as the engine was throttled up, the flywheel would slip back throwing the timing off. I'm not saying this is what has happened with your machine, but it can be a real head scratcher and may be worth checking into. All the best,

Sky

[plpitts1]

Thanks Skywatcher, I will take a look at that in the morning as well.
Pat

[plpitts1]

Started with checking the coil, Fly wheel looked good, regapped coil with Echo gap gauge, checked metering lever with Zama meter tool, adjusted just a hair. No change.
Tuning the carb - Echo says initial setting is L= 3 3/4, H = 1. This is close to where they were at. Tried adjusting with no change.
??????
Pat

[bgsengine]

and how long has it been run since? Possible crankcase still loaded with excess gas, too. Also, operating engine with all blower tubes fully attached? Any adjustments need to be made with all OE tubes in place, they offer up the load (blowing air) and if they are not in place or altered, engine performance will suffer. Also, pressure test the fuel system? (may have a bad fuel tank vent that is allowing too much pressure build-up in tank - perhaps try it with tank half full and fuel cap off?) finally, with air cleaner off, look into carb bore at the throttle valve and rotate to wide open - when fully open, the hole in throttle rotary valve should line up perfectly all the way around with the machined bore in the carb throat. If not, you may have lost the lift roller (very tiny, just 1mm diameter, easy to lose if carb is taken apart by someone that doesn't know it is there) also the low mix adjustment needle, that's a very tiny adjustment screw that is right down the center of the rotary valve (many do not know that, and try to adjust the idle stop screw instead) and finally, obviously air cleaner can affect things - even one that "looks" clean visually can be plugged (same with fuel filters, by the way)

just a few other points to consider..

[plpitts1]

Thanks bgsengine, I will take a look at the these items you mention. I did try loosening the cap while running, does not change anything, and the problem starts at start up, seems like if it where a vent problem it would take a bit. And blower tubes are in place. Definitely adjusted the low speed adjustment screw in the center of the rotary valve as I had to removed the plug. Also have new air filter, spark plug in place. I also tried new carb, so that would eliminate throttle valve problem I believe. Will take a look at the other items on you list. As far as the excess fuel in the crankcase, is there a way to check that without disassembly? It does seem possible as the spark plug and muffler get really wet and it seems to run rich.
Thanks again for you response,
Pat

[bgsengine]

As far as the excess fuel in the crankcase, is there a way to check that without disassembly?

Take the plug out, muffler off, tip engine sideways with exhaust port down and crank over engine a bunch of times, see if any raw fuel comes out (or spray) and can leave it set in that position with piston at bottom center for a little while and let things drain and dry out. I have sometimes had people come in with flooded 2-strokes that just don't seem to clear up until leaving them set with fuel tank empty (or line unhooked from carb) overnight that way, then a new plug, fires right up and tune and they have no more problems. most of the time it is because of over-choking (They don't spot the rich "pop" and leave choke on and flooding gets worse and worse) many times they bring them in a day after they have the problem, and after clearing the flood, they start right up and run fine. I'd still check the throttle bore alignment even on the new carb, if not sourced from reliable distributor in a fresh new box (unopened) always a possibility someone bought it , removed the roller (cause they lost it and dont know how to find a replacement) and then return the carb as "didnt fit" and it gets re-sold.

[plpitts1]

Thanks bgsengine, will give that a go.
Pat