Is a Spark Arrestor really Necessary?

rgrottk

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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.
Unless you in a fire zone with 4 foot high dry grass (Africa) you don't need a spark arrestor.........
 

deminin

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Unless you in a fire zone with 4 foot high dry grass (Africa) you don't need a spark arrestor.........

That's the way I see it. Yesterday, I went through all my other Stihl stuff,...2 chainsaws, my bigger weed eater. and small cultivator. The only one which showed any buildup was the MM55 cultivator....but torching it, and cleaning with a wire brush took care of that. My old fs45 is about 10 years old, and I'd never cleaned it, so that's probably why the buildup was so bad. In the future, I'll add this task to my yearly maintenance, and if I find these arrestors deteriorating, I'll just remove them. In this area, the only time we have any dry grass is in the Winter....and I seldom do anything with my stuff, during the cold months, other than do some good Winter prep and storage, so they work next year.
 

slomo

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I remove them because the engine sounds better. Like to wake up the neighbors at 06:00am. The ones that "allow" their dogs to crap on my grass.

slomo
 

Rocky J

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I took mine out because it was plugged up ,then mine ran such a high RPM it made my hand itch and almost felt like I was getting shocked . I was afraid it was going to scatter parts and take out my manhood so I cleaned the screen and put it back in. I know on the older 2 stroke mopeds they welded a washer in the header pipe to restrict the exhaust to control the top end RPM's
 

Hammermechanicman

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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.
Not really. I see stihl trimmers and blowers all the time running E free gas with the HP ultra oil at 50:1 with clogged arrestor screens all the time.
 

slomo

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Toss the stinking screens unless you are a logger in a forest or similar tree huger place.

slomo
 

bertsmobile1

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For all you who think they are useless, fire up your tools late at night & watch just how many burning embers fire out of the exhaust,
A lot more than most would expect.
Now weather they are sufficient to actually start a fire, I would leave that to the experts but by virtue of the fact the bone lazy politicians have passed laws requiring them to be fitted , it must have happened at least once .
Down here only chain saws, water pumps & generators are required to have spark arrestors fitted
 

mecanive

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in my mind the spark arresoor have 2 jobs first ont prevent fire second give an acceptable level of noyse the most cause to clug the screen is une some ethanol gasoline always une super gaz with no ethanol
 
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