PAS-225 won't stay running even with carburetor cleaned

[fireman949]

My 10 year old PAS-225 will not stay running for long. With the choke at 75% and feathering it, I can keep it going, but not to where it can do anything useful.

I've never used ethanol gas in it, and always used the correct fuel/oil mix. I took the carburetor apart and found exactly what I'd expect on a 10 year old trimmer that only used non-ethanol fuel and in a 1/2ac residential setting only - no problems. Everything looked 100% but I cleaned what tiny amount of anything was on or in it with the same results. The spark plug, fuel filter, and air filter have all been changed. I removed the blocker screw to expose the fuel/air mix screw under the primer bulb and attempted a few adjustments with no change in behavior.

There isn't much resistance when pulling the cord.

We did move from Mississippi (450ft) to Colorado (6600ft) about 4 years ago, but it ran well for a while. I suspect the engine has lost compression, is there anything else I should do or try before calling it?

If this one is indeed dead and I get a replacement - I have several attachments as this was the pro attachment system and our property in CO isn't even 10,000sq. I'm OK with another $200 PAS-225, and I suspect with continuing on non-ethanol fuel, I'll get at least 10 years out of the next - is there any other options I should consider? On a new one

 

[Rivets]

if you have been using the old bottles of 2-cycle oil, I have found that carbon and oil will build up in the muffler. Since I’ve had my customers switch to the new synthetic oils, (I switched to Opti-2), I no longer see this problem. Try removing the muffler and make sure it is not partially clogged. If exhaust gases cannot get out, enough fresh fuel cannot get in. I take my propane torch and get the muffler very hot to burn out any carbon or oil residue.

 

[fireman949]

Here is a video of it running. I also noticed when I took the carburetor apart there is a chunk missing off the plastic. I'm wondering if a new carburetor is the fix.
If I feather the choke, I can keep it running. If it's warm and I squeeze the throttle, it'll stay wound up with the choke off until I let up on the throttle and then it dies and doesn't want to restart without choke. I think it has enough compression and when I took off the muffler, the behavior was the same. I did a 'window' inspection of the piston with the muffler off and it looks fine - no scoring or anything funky.

Just to eliminate it as a possibility, I did pickup some 50:1 premixed fuel at the hardware store, emptied all the fuel I could out (removed carb) and same results.

 

[bertsmobile1]

New carb time

 

[fireman949]

New carb time

Ordered one today - $17 and should be here tomorrow. Hoping for another 10+ years, but $16 isn't bad.

 

[fireman949]

Unrelated, but if I bump a 10 year old thread with my experiences would that be taboo in these forums? I'd love to put my experience of using the Hustler in the thread I'm linking below, but if it'd get negative comments for being a bumped 10 year old thread, I won't:

1/2 acre - replace my walk behind with a Toro SS4235 ZTR for time savings?

We built 6 years ago on a 1/2 acre lot. Subtract the house, driveway, and a few raised garden beds and there is about 15,000 sq ft to mow. 6 years ago I bought a Husqvarna 5521CHV (Honda) easywalk self propelled mower with a 19" cut. It's been an awesome mower. Other than gas, yearly oil...

www.lawnmowerforum.com

 

[bertsmobile1]

Go ahead.
A lot of people read the archives and never post
Also do not be surprised if your $ 19 carb does not work
Most of the cube carbs sold on Amazon & ebay are QC rejects bought as scrap metal for a few cents then sold to cheapskates as "Fits a " or "OEM for" nowhere in the description does it say that the carb works or has passed QC .

 

[fireman949]

Understood. The one I bought was from Huztil for the PAS-225 4.7 of 5 stars with 4700 reviews looked like a fairly safe bet. OEM was $65 and I don't mind doing that either if this one doesn't work.

 

[bertsmobile1]

Did not know Huztil ( mostly Farmer Tech parts ) sells on Amazon now days .
Their stuff is generally good

 

[fireman949]

All done and it runs like it should. It started after the 2nd pull and I almost always allow a 60-90 second warm up before full throttle.
I hope to get another 10 or more years out of it.