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grass trimmer


wwc's Avatar
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07-10-06, 05:28 PM   #1  
grass trimmer

I have a ryobi 31cc 15" weedeater model 700r.

I am having a hard time keeping it running.
I can get it to start like normal with the choke to the left all the way and when it "hits" I move it near center position and it will run kinda.
I have the throttle trigger pulled all the way and I have to play with the choke lever so that it's just slightly to the left of center, any more than that even when it's completely warmed up i can never move it all the way to the right to the choke off position.
The trimmer is never running full speed this way but it's the only way i can keep it running.
I have removed and cleaned the spark plug but that made no difference.

What is causing this?

 
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07-10-06, 06:12 PM   #2  
Posted By: wwc I have a ryobi 31cc 15" weedeater model 700r.

I am having a hard time keeping it running.
I can get it to start like normal with the choke to the left all the way and when it "hits" I move it near center position and it will run kinda.
I have the throttle trigger pulled all the way and I have to play with the choke lever so that it's just slightly to the left of center, any more than that even when it's completely warmed up i can never move it all the way to the right to the choke off position.
The trimmer is never running full speed this way but it's the only way i can keep it running.
I have removed and cleaned the spark plug but that made no difference.

What is causing this?
Could be a bad diafram. Remove and clean the carb and replace the diafram.Also note in what order the gasket and the diafram go on get this wrong and it will never run right.

 
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07-10-06, 06:21 PM   #3  
can you explain why you think it's the diaphram, You could be right i'm just trying to understand how the diaphram would cause this.
Thanks

 
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07-10-06, 06:42 PM   #4  
wwc,

Clean or replace the air filter first. If no change, remove and clean the carb with spray carb cleaner. Make sure to hit all tiny holes. Blow out with high pressure air. Replace all gaskets and the diaphragm which; will not haunt you later by vacume leaks which you may have.

The importance of the diaphragm not leaking is if it sucks air it's not suppling fuel which needs to be compensated for by you having to partially close the choke which also reduces intake air; inturn it induces the engine to find a slower speed because of the lower fuel to air mixture. You may also need to clean the exhaust port.

God Bless,
Dave237


Last edited by dave237; 07-10-06 at 06:59 PM.
 
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07-10-06, 09:30 PM   #5  
wwc
The main job of the diaphragm is to pump fuel to the combustion chamber. What mother nature does with the fuel nowadays is to make it go stale and when it does, it stiffens up the rubber in the diaphragm and it will not pulsate the way it is designed to do. This is the cheapest and the first method most small engine companies will work with. If it was working well before the season, then this is the first thing you want to look at. It 's the usual process of elimation.

snoman

 
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07-10-06, 11:28 PM   #6  
If your diaphragms are dried up there won`t be enough flexibility to open the inlet lever or operate the pump properly.

The diaphragms operate the carburetor

 
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07-11-06, 08:41 AM   #7  
Thanks guys, i'll tear into it today and see what happens.

 
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07-11-06, 03:53 PM   #8  
I tried it without the air filter and housing and it still ran the same.

I took the carb off and apart and looked at the diaphram, it wasn't torn or hard i think.
It was flexable but some what stiff, like stiff cloth type paper feel to it.
I couldn't get a kit for the carb today so i'll try tomorrow.

can i just buy the diaphram for the carb or do i have to buy a rebuild kit.

how much is this gonna set me back.

 
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07-11-06, 09:02 PM   #9  
You should be able to get the whole kit for less than $20.


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

God bless!

 
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