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What is wrong with this weedeater?


ghunt81's Avatar
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04-28-16, 01:11 PM   #1  
What is wrong with this weedeater?

I posted about this last year but still having the same issues.

I have a Murray cheapo weedeather that I bought 3-4 years ago. Gave me almost no problems for the first couple years I had it, now it gives me nothing but problems.

I took it out of storage this year, it would start but wouldn't really run. I took the carb apart and found out the screen inside of the carb was almost completely covered up with some crap that almost looked like very fine wet sand, any idea what that would be?

Anyway I cleaned it out, it started easier and ran better, but it won't idle (had this problem last year), as soon as you release the throttle it just shuts off. I used it for a little while yesterday and after 20 minutes or so it was running crappy again, like if you hold it at full throttle it's running at maybe half.

I have this PB Blaster "tune up in a can" stuff, if you take off the air filter and spray it into the carb while it's running the thing takes off and runs great, like it normally should, until it burns off (which is only a few seconds) then it goes back to how it was.

So it seems to be a fuel issue but what do I need to look for? I sprayed out all the fuel passages when I had the carb off, maybe I need to disassemble it and give it an even more thorough cleaning. Already replaced the carb on this thing once, I don't understand what the problem is.

 
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04-28-16, 03:42 PM   #2  
Still trying to use ethanol gas?
Find a place selling non ethanol.
Changed the fuel filter inside the fuel tank?
Left the fuel in the tank over the winter? Never do that!
I've bought a funnel with a fine screen in it, amazing the trash I see clogging the screen even with new fuel and a new gas can.
Just trying to spay anything in the carb. is not going to a thing to clean it.

 
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04-28-16, 07:23 PM   #3  
Nobody around here sells non-ethanol gas unfortunately.

I thought I dumped the gas out before winter but now I can't remember. I'll have to see if I can get the fuel tank off and check the filter.

 
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04-28-16, 08:00 PM   #4  
I'm guessing the filter either came off, the fuel line broke, or the filter is breaking down and that is where the fine sand like material is coming from.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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04-29-16, 05:17 AM   #5  
You have a problem with the idle function of your carb. If you can tell us the make and model of the carb, I should be able to help you.

 
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04-29-16, 05:27 AM   #6  
When you replaced the carb, did you replace the filter in the tank as well? Does it have high/low idle mixture screws? I believe that is a Zama carb if I remember right......you can get a rebuild kit for it for about 10 bucks on Amazon. This will include your diaphram and all the guts to it. Let it soak overnight in carb cleaner, then blow it out with carb spray all the ports including the jets, then compressed air into all the ports. She should perk right up!!

 
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05-04-16, 12:54 PM   #7  
It is a Walbro carb.

I took the tank off the other night, took the "filter" out and removed it from the tube. Everything looks OK with it far as I can tell? So it's just a piece of hard foam right? I took that piece off and ran my finger across it, it doesn't look to me like it's disintegrating or doing anything weird.

I guess it's time to dig into the carb again and see what's up.

It has to be a fuel issue, it starts easily enough, but won't stay running with no throttle, and I'm definitely not getting WOT out of it either. Maybe I should just look for another carb for it, I think I only paid $20 for this one last time I replaced it.

EDIT: Hell, I can get a new carb off ebay for $13. However I can't seem to find a fuel filter like the one it uses, does anyone know where you can get those? Or can I use a different style?

 
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05-04-16, 10:08 PM   #8  
You can get the filters on e bay also. It's a poulan style filter.

I deal with HL supply and got a friday deal 59 cents for a Husqvarna 3.00 filter I ordered a A$$ load of them and pull handles for a buck also.

I got a Craftsman weed wacker/ Mtd from the salvage yard last week. No throttle handle assembly but the cable and kill switch was there. I cleaned the carb good but it would not keep running. I soaked the carb in Berrymans carb cleaner for 2 hours put it back together and it runs like sewing machine now.

If you spend the 30 bux for a gallon of berrymans and the part basket you wont be sorry. But I work on these for a living.

 
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05-05-16, 01:06 AM   #9  
I have a mighty lite 26ss weedeater and would like to find out how to adjust high and low needle on the carb

 
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05-05-16, 05:36 AM   #10  
I dont think most weedeaters have adjustments. None of mine have at least

 
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05-05-16, 05:39 AM   #11  
And to the OP, rebuild or replace the carb. If the diaphram is even a tiny bit stiff, it wont pulse right

 
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05-05-16, 11:11 AM   #12  
Most weedeaters have adjustments but not ones that can be adjusted without special tools. Older ones had screws with slots for a screwdriver but not these days.

I like to adjust high speed first with the engine running full tilt and the correct amount of line hanging out of the head if it's on a string trimmer (it makes a difference in the carb adjustments if there is no string). Back the screw out until the engine begins to stumble, then screw it in until the engine races at peak speed, then back it out again slowly until it begins to flutter a little bit and leave it there. Do not leave it at the max rpm setting. Then adjust idle for smooth running at idle and if it bogs or dies when you give it throttle, back out on the idle screw a bit more until it revs up without hesitation.


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05-05-16, 11:30 AM   #13  
Then adjust idle for smooth running at idle and if it bogs or dies when you give it throttle, back out on the idle screw a bit more until it revs up without hesitation.
You mean the "low" speed right? Not idle?

Otherwise that's xactly the way I do it also.


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06-01-16, 05:31 AM   #14  
It's been awhile but I wanted to post to update.

So, I wasn't paying attention when I ordered my new carb and it came from China...I ordered it may 7 and just got it yesterday. Could have gotten one in the states for about the same price, live and learn.

Anyway- I put the new carb on yesterday. Also dumped out the gas tank, put on a new fuel filter and filled it with fresh gas.

So now, it starts and runs well, and I get full throttle like I should, but the damn thing still won't idle. Regardless of choke position, when you let off the throttle and the RPM's come down, it runs rough for a second or two and then just shuts off. I did notice with a very light throttle application (like just above where it might normally idle) it seems to run a little rough (you can feel it shake while it's running) almost like it's misfiring or something, but full throttle runs great. Any ideas?

 
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06-01-16, 10:43 AM   #15  
Yeah, I meant the low speed screw Scott... Not sure why I said Idle.

ghunt81, look for the two small adjustment screws side by side on the carb. Turn the one closest to the engine counter-clockwise about 1/8 of a turn. See if that helps.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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06-01-16, 12:49 PM   #16  
I just went through a simular situation,what I did was bottom out the 2 screws and back them out about 1 1/2 turns each,start it up and keep it running for a couple of minutes, then I feathered the throttle while adjusting the L screw,then while holding the throttle wide open I adjusted the H screw to optimum,when that was all set I adjusted the screw for the throttle to keep it idling.This was a Husqvarna Mondo with a Walboro carb. Check this link out.

http://wem.walbro.com/distributors/s...viceManual.pdf


Last edited by Geochurchi; 06-01-16 at 02:42 PM.
 
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06-01-16, 03:08 PM   #17  
That's pretty much the way I have always done it back to when I was a kid, Geo. The exception is after you get max rpms at WOT back out the H screw until you get a small drop in rpms. That gives you a little richer mixture for lubrication and cooling. Then go to the throttle stop to set the idle speed.

 
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06-10-16, 12:50 PM   #18  
Can you use anything besides the specialty tools to adjust those screws? Or am I going to have to order one of those tools?

 
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06-10-16, 03:28 PM   #19  
It depends on what type of screws you have, there are at least 5 different types that I know of.
Sometimes you can use a butt splice on the splined screws.


Just needs a bigger hammer
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07-14-16, 11:36 AM   #20  
So to dig this up again...mine has the "pacman" screws so I bought a tool off ebay.

I started the weedeater and adjusted the low speed screw to where it would not shut off. However it's running too high as it's above idle and it's spinning the head instead of leaving it neutral like it should be. If I turn it down any below that point it runs rough, shakes, and shuts off after a couple seconds.

I don't get what's wrong with this stupid thing, I guess I'll just leave it running too high, at least it won't shut off every time I take my finger off the throttle. I think it's having fuel pickup problems but I don't understand why. When I hold it horizontal it runs alright but when I tip it downward the RPM's drop. I dunno.

 
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07-14-16, 01:57 PM   #21  
There should be a screw that is not "special" that you adjust for speed of idle, it adjust the throttle not the carb. Have a good one. Geo

 
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07-15-16, 04:57 AM   #22  
You just have to patient,turn those screws slightly at a time feather the throttle a bit if necessary,you will eventually will get it,I did,my Husqvarna runs like new.

 
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07-19-16, 06:00 AM   #23  
If you're talking about the screw that also functions as the throttle stop, I did adjust that one, didn't seem to do much...it was adjusted most of the way in already anyway.

 
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07-19-16, 08:27 AM   #24  
The screw that functions as the throttle stop is the screw I am referring to, you should be able to turn that screw and almost go from no throttle to full throttle so something must be miss aligned . Have a good one. Geo

 
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