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View Full Version : Shindiawa Line Trimmer, Weak, Slow RPM at Full Throttle?


D_C
09-22-2009, 01:43 PM
My Shindiawa Line Trimmer is weak, and RPM is slow at full throttle.

New spark-plug, New fuel, in-tank fuel filter flows, relatively new carburetor, clean foam filter, flywheel/magneto-pickup is clean.

It starts and runs, but even at full throttle, RPM is slower than usual and the trimmer head is easily slowed during use. The carburetor butterfly is opening and closing fully with the trigger control.

RPM picks up when I spray tiny blasts of PB Blaster Small-Engine Tune-Up.

What is likely wrong and how can I further test/diagnose?

Thanks

Breezmister
09-22-2009, 06:39 PM
My Shindiawa Line Trimmer is weak, and RPM is slow at full throttle.


When was the last time you cleaned out the exhaust port and removed the spark arrester screen ?

cbegap
09-22-2009, 08:14 PM
Yea I would check those two things ASAP. I just pulled the muffler from my Echo 265T today and the spark arrestor was fine but the exhaust port was really restricted. I had used the PB Blaster tune up down the spark plug hole before so I was surprised that there was still so much carbon still there after using that stuff. So after I pulled the muffler I scraped as much as I could with a screw driver and then turned the trimmer upside down, put the piston up past the port and then filled the port with the pb blaster tuneup and let it soak but didn't let it dry out. It worked well because the trimmer now works like new.

D_C
09-22-2009, 09:55 PM
Thanks. It has been a while since I checked it, and I will do it ASAP, but if that is the problem, why does it speed up only when I spray PB Blaster Small Engine Tune-Up, then once running just fuel/oil mix, it slows back down.

Oh well, I'll check/clean the screen and let you know.

Thanks.
Derek C.

Breezmister
09-22-2009, 10:10 PM
I pulled the muffler I scraped as much as I could with a screw driver and then turned the trimmer upside down

Just be careful using a screwdriver.

D_C
09-23-2009, 03:01 AM
I pulled the screen and then the entire muffler.

It was a bit dirty, but did not appear to be particularly bad/blocked. I cleaned (scraped carbon out of) the cylinder exhaust port, then cleaned the spark-arrester screen and muffler with Oven Cleaner, solvent, soap & water, etc. It is very, very clean now.

Will try starting/running the unit in the morning. Hoping for the best (that that was the problem,) but I'm not confident that "screen blockage" is the cause.

Will let everyone know the results as soon as I test run.

D_C
09-23-2009, 01:24 PM
Well, I started the trimmer this morning. It started first pull, but instantly died. I fussed with it some more and got it running.

Had to play with the carb mixture adjustment and let it warm up, but it seems to be running back at full RPM.

Looks like you were right. The arrester-screen was dirtier than it looked. Clear enough to start and run at low RPM, but dirty enough to keep it from running at full operating speed.

I had cleaned it in the past few months, but it is getting older and must be fouling quicker than it used to.

In any event, Thank You very much for the correct advice/diagnosis. :)

Alan0354
09-23-2009, 11:19 PM
I am curious on about how many hours of running before you have problem of the stuff buildup in the exhaust port? Hundreds of hours or less?