Echo PE-230 weak throttle

[Riles32807]

Hey guys,
I bought a Echo PE-230 stick edger off Craigslist, the fuel lines were rotted (should have see the guy pulling on it trying to show me that it starts with gas going everywhere. .) Got it home & replaced fuel lines, checked filter & tank vent. Cleaned the carb & replaced the diaphrams. Replaced the spark plug (very dirty) & someone else had already pulled out the spark arrest. The idle took a little tuning. Here's my problem, WOT it just doesn't seem to rip like it should. If I close the H screw all the way it will stall, more than about 1/2 turn out, with the air filter off, I get a little fuel misting out the intake, further out it sprays more but doesn't seem to effect the motor. I cleaned the carb again and still the same thing. Any thoughts?

 

[Conquistador3]

I don't know what carburetor yours came with, but I am ready to bet it is the problem.
Those Echo powerheads usually came with either Walbro WT's or Zama RB-K's and neither is known to respond well to a rebuild. Either you succeed at first time or will be driven insane trying to understand what is wrong: I have wasted enough time on those things to come to the conclusion if a clean and rebuild don't help, they just get replaced.
Chinese clones of Walbro WT's are one fifth of the original and easily available on eBay, while I think the Zama is cheap enough your side of the Pond to give Chinese clones a run for their money.

The only other thing I could think of is the fuel filter. Aftermarket ones are complete junk: many seem to either choke fuel flow or to have problems keeping it up when fuel in the tank gets low. If you put in one of those Zama or Walbro clones, buy a genuine filter and don't look back. Unless you mix your fuel with mud it should last at least five years regardless of usage.

 

[Riles32807]

Thanks Conquistador, it's a zama RB-K70. Guess I'll go through it one more time and replace it if that doesn't work, $15-$20 e-bay isnt too bad.

 

[Conquistador3]

Thanks Conquistador, it's a zama RB-K70. Guess I'll go through it one more time and replace it if that doesn't work, $15-$20 e-bay isnt too bad.

The problem with Walbro WA's and WT's (and I take Zama RB-K's as well) is they have a small, non serviceable valve you cannot access. Ultrasonic cleaning, pure acetone/carb cleaner baths etc followed by judicious applications of compressed air (no more than 3/3.5bar in short bursts) may help dislodge whatever has gummed up that valve, but don't lose your sleep over it.
It's a poor design, and there's a good reason it has been steadily falling out of grace to be replaced by more expensive but also far more serviceable designs.

 

[Cope1024]

Thanks Conquistador, it's a zama RB-K70. Guess I'll go through it one more time and replace it if that doesn't work, $15-$20 e-bay isnt too bad.

I bought a Chinese carb on eBay for my Stihl 025. The OEM had only Lo adjustment and the clone had Lo and Hi. Saw runs much better. I have a kit for the OEM, but I probably won't bother rebuilding it.

 

[Conquistador3]

I bought a Chinese carb on eBay for my Stihl 025. The OEM had only Lo adjustment and the clone had Lo and Hi. Saw runs much better. I have a kit for the OEM, but I probably won't bother rebuilding it.

It's the clone of the carburetor used on non-EPA saws: the MS250/025 we got here and the MS250 still sold in countries like Brazil has a fully adjustable carburetor. The EPA carburetor had a fixed "High" needle for emission purposes.
And I don't know about the US model but the MS231/251 still has a fully adjustable carburetor, or at least mine has. Never felt the need to adjust it though: it runs too well for being a clamshell.

 

[Cope1024]

It's the clone of the carburetor used on non-EPA saws: the MS250/025 we got here and the MS250 still sold in countries like Brazil has a fully adjustable carburetor. The EPA carburetor had a fixed "High" needle for emission purposes.
And I don't know about the US model but the MS231/251 still has a fully adjustable carburetor, or at least mine has. Never felt the need to adjust it though: it runs too well for being a clamshell.

Those little homeowner Stihl saws are better than they're supposed to be. On another note, I just bought an Echo ES-250 shredder/vac. It has no Lo adjustment but does have Hi.