Echo ES-250 Starting / Running Issues

[Ezatnova]

Hello,

I have an ES-250 that has run great for many years. Last few years have only used Trufuel and I use it year round so it never sits long with old gas.

Went to start it last week and it was giving me a real hard time. Definitely primed, Choke or no choke (it was 95° out), air filter completely off or on like normal, throttle open or closed…wouldn’t start for about 50 pulls. That has never happened before.

Finally puttered and stayed alive, and seemed to run functionally well. However, I noticed a burning smell that really almost smelled like burning plastic, but could have been an oil smell. I then noticed puffs of smoke coming from inside where the engine and muffler are.

I shut it down and it wafted smoke for five minutes or so and then stopped.

I figured after 8 years or so, might need a freshening up. So today I put on:
- new carb
- new prime bulb
- new lines including new fuel filter and bleeder
- new air fil
- new spark plug

Added some fresh TruFuel and was ready for a brand new machine. Except again it wouldn’t start. Finally after 20 or so pulls, it puttered to a start and then ran.

Ran and used it for about 5 minutes and have a few observations, but maybe I’m being skewed by it still not starting well. I swear it is down on power/air flow and also sounds grittier (but to be fair I am almost always using it with earbuds or earplugs in).

Finally, I also smelled some of the burning smell, but not as bad. When I shut it off, there were 3 or 4 wafts of white smoke and then it stopped doing that. Smoke could possible have been from residual leakage that still had to burn off?

I’m just worried that the carb wasn’t the issue and that the compression is shot in the motor somehow and oil/fuel is leaking through to the exhaust? Trying to figure out I’m better off chucking this whole thing in the garbage and sucking up the $250 for a new one vs continuing to use this if it’s not worth it, or even dangerous.

Attaching a video of it running after the refresh. Maybe someone with trained ears can tell something. Also, I realize this isn’t a Bentley motor, but is it odd that, even after it’s warmed up, sometimes 100% throttle runs a less rpm than 95%, or so?

Thanks!

Echo ES-250 after new carb

youtube.com

 

[bertsmobile1]

Remove the muffler and check the exhaust port
Good chance it will be carboned up .

 

[Ezatnova]

Remove the muffler and check the exhaust port
Good chance it will be carboned up .

thanks!

It makes sense since it’s running so hot. There is a little guard piece angling there gasses out of the muffler. Is that what needs to come off? That area and those bolts are sort of blued in color from the heat, and with just a screwdriver T27, I can’t break them loose.

Or, do I need to remove the next bigger piece (the muffler itself?)?

thanks!

 

[Ezatnova]

Ok. Pulled the exhaust muffler screen and it looks fine to me?

The brand new spark plug is AWFUL with wet black after only 5 minutes of life. Mega rich??

thoughts?

 

[Ezatnova]

Interestingly, here’s my old spark plug that came out with the rebuild I did today. WAY less black wet soot than this brand new one, above.

i wonder if this new carb is junk and jetted wrong?

 

[bertsmobile1]

Interestingly, here’s my old spark plug that came out with the rebuild I did today. WAY less black wet soot than this brand new one, above.

i wonder if this new carb is junk and jetted wrong?

View attachment 61705

Did you buy it from a mower shop or do an Evaby/Amazon lucky dip
I don't know how many good ones are sold through them but I do get a lot of stuff with brand new carbs on them that are obvious quality control rejects , fished out of the scap bin and sold as OEM for xyz

 

[Ezatnova]

We MIGHT have had a red herring here!

after looking at the exhaust port that was quite clean, I was thinking about the mega black wet spark plug and it running so rich.

Unless I’m missing it, I don’t see how the jets on this carb are adjustable. So next thought…making sure I attached the right hoses to the right ports from fuel tank to carb.

While I did verify the hoses were going to the correct places, I also noticed something else. The vent hose and the return hose were super long compared to the OEM setup, where they only extended 1/2” down from the grommet. These were inches down and INTO THE FUEL.

So I took pulled those lines way up, snipped the excess and reattached to the one way vent and return port.

The cylinder was flooded with fuel and carb cleaner so it needed two pulls to start, and the was spitting out of the muffler outlet port slots, but then it settled in and really seems smooth now! I didn’t want to lay into it and test power sound after full throttle since it’s 9:30pm and people might not be thrilled.

Anyone think those two hoses that were extended down into the fuel could have been my problem running so poorly and rich after the full refresh?

 

[Ezatnova]

Did you buy it from a mower shop or do an Evaby/Amazon lucky dip
I don't know how many good ones are sold through them but I do get a lot of stuff with brand new carbs on them that are obvious quality control rejects , fished out of the scap bin and sold as OEM for xyz

it was the Amazon $26 special

 

[bertsmobile1]

Should not make any difference as the carb should have check valves in it
A blocked tank breathing system can overpressurise the fuel tank so that the metering needle unseats which floods the engine
THis is the "pop off pressure" that every idiot on face book / U-tube who thinks they know about engines is obsessed with and professions who do know never bother with
The carb should hold ≈ 7 to 10 PSI inlet pressure for a good 10 to 15 minutes
If the metering needle it too low then the carb will flood easily
At the factory every one is tested
Pass => goes to Echo
Fails => goes to a rebuilder for correction & resale
Want to know how many bad meetering diaphragms I find on brand new ebay / amazon carbs ?

 

[StarTech]

Should not make any difference as the carb should have check valves in it
A blocked tank breathing system can overpressurise the fuel tank so that the metering needle unseats which floods the engine
THis is the "pop off pressure" that every idiot on face book / U-tube who thinks they know about engines is obsessed with and professions who do know never bother with
The carb should hold ≈ 7 to 10 PSI inlet pressure for a good 10 to 15 minutes
If the metering needle it too low then the carb will flood easily
At the factory every one is tested
Pass => goes to Echo
Fails => goes to a rebuilder for correction & resale
Want to know how many bad meetering diaphragms I find on brand new ebay / amazon carbs ?

Sorry Bert but you got three things wrong here.

First the tank vent only prevents the fuel tank developing a vacuum. Actually the tank needs some pressure so the carburetor fuel pump works more efficiently.

Second setting the metering lever too low will not cause flooding but instead cause a lean burn condition. It is setting it too high that will cause either an over rich condition or flooding.

Here is a troubleshooting chart for the Zama RB carburetors.