Stihl FS 55R weed Wacker

johnorlandi

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Hi Guys

I have a Stihl FS55 R weed Wacker that I am using a lot of gas. I used to do the entire yard on a full tank of gas but now it is taking a tank and a half. I re-adjusted the carb and put in a new air filter, the plug looks good, and the spark arrestor is clean. Gas is mixed correct. Any ideas?
 

Auto Doc's

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Hello John,

Have you looked down into the plug hole to check the cylinder for scoring? You can also remove the muffler to actually see if the side of the piston is scored.

Are you using the correct number spark plug it calls for and not just one that fits?

Are you using a different 2-stroke oil in your mix?

Is the string head spinning freely like it should, or is it tight from gear binding due to lack of lubrication?

Otherwise, it sounds like the engine is getting tired and losing compression with age and use. Maybe a small about of extra oil in your mix will help
 

Tiger Small Engine

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Hi Guys

I have a Stihl FS55 R weed Wacker that I am using a lot of gas. I used to do the entire yard on a full tank of gas but now it is taking a tank and a half. I re-adjusted the carb and put in a new air filter, the plug looks good, and the spark arrestor is clean. Gas is mixed correct. Any ideas?
Possible fuel leak?
 

StarTech

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When was the last time the metering diaphragm and inlet needle been replaced? And also is the metering lever height set at the correct height?
 

johnorlandi

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Hello John,

Have you looked down into the plug hole to check the cylinder for scoring? You can also remove the muffler to actually see if the side of the piston is scored.

Are you using the correct number spark plug it calls for and not just one that fits?

Are you using a different 2-stroke oil in your mix?

Is the string head spinning freely like it should, or is it tight from gear binding due to lack of lubrication?

Otherwise, it sounds like the engine is getting tired and losing compression with age and use. Maybe a small about of extra oil in your mix will help
 

johnorlandi

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Thank you for responding Auto Doc
Plug = I had a E3.12 that was about .030 and replaced it with a new auto lite gaped at .020
Cylinder = I removed the muffler and the wall looked really good and from the plug hole it looked good also, a little wet carbon on the top of the piston but really good.
Oil = I use Stihl 5.2 oz to 2 gallons of gas
String head = I grease this a couple of times a year, so it moves freely.
Did a compression test and had trouble reading the gauge when pulling the starter rope but it looked like 60 psi or more.
Let's see if the plug change does anything and if not, I will try what Star Tech says about the carb. It won't be for about a week or so before I use the weed Wacker but I will let you know

Thanks again
 

johnorlandi

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When was the last time the metering diaphragm and inlet needle been replaced? And also is the metering lever height set at the correct height?
Star Tech. Thank You
I Have not been into the carb for a real long time, but I will keep that in mind. See my response to Auto Doc
Thanks again
 

johnorlandi

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Not sure I will keep check. I do not see any gas around but I will take a better look the next time I run
Thank You
 
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