How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask PK. Your Own Question
PK., Small Engine Technician
Category: Small Engine
Satisfied Customers: 1052
Experience:  Retired Owner of a full service shop and national parts sales website.
Type Your Small Engine Question Here...
PK. is online now
A new question is answered every 9 seconds

My Poulan Pro 335 weedeater would start and run at idle speed,

Resolved Question:

My Poulan Pro 335 weedeater would start and run at idle speed, but slow down and die when I tried to speed it up -- unless I constantly revved the engine, and even then it would eventually die anyway.

After communicating with Russ, I cleaned the air filter (which really didn't seem dirty at all) and cleaned the muffler using aerosol carburator cleaner. When I reassembled the 'eater, it would not start at all -- not even a hit. I replaced the spark plug which was fouled. Still no luck. I turned the carburator screw all the way in and then after backing it out 1-1/2 turns tried to start it. I kept backing it out 1/4 turn each time, but no luck.

What now? (Right now the stream that runs beside my house looks like a real good destination for the weedeater. . . .)
Submitted: 5 years ago.
Category: Small Engine
Expert:  PK. replied 5 years ago.
Hi, I have a ditch out back of my shop where a few have landed......

My first thought would be that the fuel lines aren't on properly.

Will the engine run on a little hit of ether?
Customer: replied 5 years ago.


The lines were never disconnected. I have no ether available to try just now -- but the engine doesn't hit at all.


One item I faileed to mention earlier: I first cleaned the muffler guessing it might be the problem, and when I reassembled the 'eater it did start right up, only to run only at idle. Thinking I'd not cleaned the muffler well enough, I again cleaned it using gas as before -- and when I reassembled it again, it would not "hit" at all. It's since then that I've sprayed muffler, air filter and carburator with carburator cleaner

Expert:  PK. replied 5 years ago.
Sorry, I was thinking you had pulled the carburetor to clean it.

The most common cause would be a faulty carburetor or fuel supply. Sometimes it's the in-tank fuel filter, sometimes the fuel lines are leaky and sometimes it's the carburetor itself that needs to come apart and be rebuilt thoroughly.

First thing to check would be that the cylinder is tight. There should be 4 screws on the bottom of the engine that hold the cylinder to the crankcase. 2 cycles require the crankcase to be sealed and there are crank seals on either end of the crankshaft. Testing the sealing ability of the crankcase requires a vacuum/pressure pump and the appropriate block off plates so that's generally not something you would be able to test at home. But the cylinder screws do come loose and that is a known issue with Poulan/Weedeater. The thread locking material they used has been failing after a couple seasons and we repaired using LocTite.

So I would start with checking those cylinder screws, then moving on to rebuilding the carb, replacing the fuel filter and lines. That's an annual maintenance on a commercial 2-stroke and should be done every two years on a homeowner model.

If it's not hitting at all on ether, then you would want to do a compression test and see at a minimum 100psi. These are singe-ring engines and do often suffer from a stuck ring and cleaning fluid in the cylinder could cause a stuck ring.

Also if it won't hit on ether, you would need to check that the plug is still firing. If not, then we can start looking for that problem before looking at the carb.

I've had more than one of these come in for a warranty repair with a sheared flywheel as well so that would be a concern a little further down the list.
PK. and other Small Engine Specialists are ready to help you
Customer: replied 5 years ago.
Thanks, I'll get busy on that checklist and follow up with you again, if necessary. I appreciate your help!

Related Small Engine Questions