Is a Spark Arrestor really Necessary?

deminin

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Yesterday, I tried to fire up my FS45 trimmer, and it was very hard to start...15 or 20 pulls to get it going, and then, it barely ran....giving it any throttle killed the engine, and it was spewing some black stuff out of the exhaust. I finished my trimming with my other weed whacker, then decided to repair the fs45 today. I checked the obvious...plug, air filter, even changed the fuel filter....no help. Then I pulled the spark arrestor, and it was completely clogged. I tried burning the carbon with a torch, but had minimal luck. I soaked it in some gasoline for 1/2 hour, dried it off and torched it again...still couldn't see much clean screen. Finally, I removed the screen, reinstalled the spark arrestor plug, and then the trimmer started right up on the 2nd pull, and ran better than it has in months.

My question is...is this screen Really necessary...other than to satisfy some government regulation?? Before I spend $20 for a new arrestor, which may clog up again in the future, I would like other opinions on this.

Thx, in advance.
 

Scrubcadet10

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What oil to gas ratio are you running?
there are also a few OEM stihl arrestors on ebay for about $10-$13
 

cpurvis

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Is it really necessary? I don't think so. My 'cleaning' consists of throwing them away.
 

deminin

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What oil to gas ratio are you running?
there are also a few OEM stihl arrestors on ebay for about $10-$13

I run a 50/1 ratio in ALL my Stihl tools, and I run premium unleaded 93 octane gas. I saw the arrestors on EBAY and Amazon, and the "price" isn't any big deal. I just wonder if these things are really necessary....they look like just another reason for engine troubles. I suppose that if a person was doing some chain sawing or trimming in a drought stricken area with dry vegetation all around, they might need that small bit of extra caution, but around my area, finding a day or two without rain is often difficult.
 

deminin

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Is it really necessary? I don't think so. My 'cleaning' consists of throwing them away.

I'm beginning to think the same. I've got 2 chainsaws, 2 weed eaters, and a cultivator...all Stihl. After seeing this, anytime I have an engine issue, the arrestor will be one of the first things I check....and probably toss.
 

Fish

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Most of the stuff running here in Ky. have no spark arresters. If yours get clogged, also wash your air filter with hot soapy dishwater.
 

Fish

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Yesterday, I tried to fire up my FS45 trimmer, and it was very hard to start...15 or 20 pulls to get it going, and then, it barely ran....giving it any throttle killed the engine, and it was spewing some black stuff out of the exhaust. I finished my trimming with my other weed whacker, then decided to repair the fs45 today. I checked the obvious...plug, air filter, even changed the fuel filter....no help. Then I pulled the spark arrestor, and it was completely clogged. I tried burning the carbon with a torch, but had minimal luck. I soaked it in some gasoline for 1/2 hour, dried it off and torched it again...still couldn't see much clean screen. Finally, I removed the screen, reinstalled the spark arrestor plug, and then the trimmer started right up on the 2nd pull, and ran better than it has in months.

My question is...is this screen Really necessary...other than to satisfy some government regulation?? Before I spend $20 for a new arrestor, which may clog up again in the future, I would like other opinions on this.

Thx, in advance.
Hell, I sell the whole muffler, bolts and gasket for $15 on e-bay...
 

Born2Mow

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Clogged 2-stroke exhausts were common back when you would run pre-mix dino oil at 25:1. These days they are basically a thing of the past if you run synthetic at the very high ratios they now recommend.

So your pre-mix ratio is wrong, your High jet is adjusted WAY too rich, or your air filter is clogged.
 

bertsmobile1

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I run a 50/1 ratio in ALL my Stihl tools, and I run premium unleaded 93 octane gas. I saw the arrestors on EBAY and Amazon, and the "price" isn't any big deal. I just wonder if these things are really necessary....they look like just another reason for engine troubles. I suppose that if a person was doing some chain sawing or trimming in a drought stricken area with dry vegetation all around, they might need that small bit of extra caution, but around my area, finding a day or two without rain is often difficult.
From the point of engine running & backp they are not necessary
And yes they are required by law in just about every forest & government park world wide for very good reasons.
Down here they are required to be fitted on all construction sites as well.
Never heard of a forest fire being started by one but I have had a few piles of sawduSt start to smoulder when cutting up logs for fire wood so I suppose it can happen.
 
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