sounds as if the gears in the head have worn out. Happened to me this summer

 

check the clutch.

 

Was the loss of power gradual or sudden?

 

You said you had check the exhaust but did you check and see if the spark arestor was stopped up. We had the same problem with all of ours after time and the screen was stopped up. You can remove by removing the screws at the exit hole. Check and see if this is the problem if it does not rev up easy. Later

 

With my Shindaiwas, I cleaned the spark arrestor, didn't help. Then I removed the muffler, there's a hole between the muffler and the inside of the trimmer's engine (very technical terms, no?) that gets a build-up of carbon. Mine was clogged almost completely. Just scrape the carbon off with something soft like a pencil. That should restore the power.

 

You said you checked the exhaust. How? I Have a 322 . After a couple of years the passages inside will carbon up the only fix is pry open the muffler(and weld backwhen thruogh cleaning) or replace the muffler. The easiest way to check for a clogged muffler is remove it and start the trimmer. If it sounds healthy and has power, the muffler is the trouble.

 

This is in adition to the obvious spark arrestor screen, forgot to mention it. I'm sure you've already checked it.and tossed it.

 

If it's running fine but not spinning, it's probably the clutch.

 

Originally posted by Tharrell
If it's running fine but not spinning, it's probably the clutch.

I have never had a clutch cause it not to spin when they go out , but the opposite, the shoes wear until the spring breaks and then the clutch fails to disengage.

As far as your power problem, first I would pull the muffler and check the cylinder and piston for scratches, gouges, and decoke the port and muffler as others have mentioned. New plug, new fuel filter and if this does not cure I would look at air/fuel ratio, i.e. crap in the carb or diaphram not supplying enough fuel. Also make sure the throttle is in fact opening the throttle all the way.

 

If it is a carbon/coke problem then ditch whatever cheesy 2 stroke oil you've been using and go with a synthetic oil like Amsoil. You will never have that problem again.

 

I really don't think it's the muffler. I took the spark arrestor off when i got it new. I've had my share of problems with those. The exhaust port didn't have any build up in it. I thought the muffler could have been plugged but i flushed it with carb cleaner and blew it out with an air hose and it seemed fine. I'll check the gearbox and clutch. I'm thinking the gearbox may be binding at higher rpms.

 

Don't guess about the muffler. Take it off and start the machine. Then you will know for sure one way or the other. For some reason the 322's are bad about it.

 

Definitely check out the muffler. You will get carbon build up over time. Especially if you run your 2 cycle mix rather rich.

We had a RedMax where the muffler can be disconnected from the engine and we could scrap off all the carbon that gathered around. When we put it back together it was like brand new.

 

I swapped mufflers with another trimmer and sure enough it was the problem. Runs great now. Boy was the old muffler plugged.