Easy Repair on STIHL FS38 Grass Trimmer - Clogged Spark Arrester

Watch this video to see what a clogged spark arrester screen will cause. Very easy repair. Visit my channel for more repair videos; www.youtube.com...

[@patrickburke7574]

Finally somebody with actual FS 38 showing what to do..... thank U

[@mattgomboso739]

I can't believe 18 people didn't like your post. I spent four hours trying to get my FS45 to run. I had given up and was googling for a new carbie. Decided to youtube my issue first and saw your clip - my stihl was bogging down exactly like you have shown. Raced outside and removed the arrester - it started and ran like a demon. Thanks for sharing your video donyboy73. Cheers, Frank from Australia.

[@donyboy73]

+Matt Gomboso you're welcome, other shop owners don't like the fact that there are how-to videos on youtube

[@longbowshooter5291]

+donyboy73 I, too, was ready to replace the carb when I saw your video. So I took it out and...... no screen at all. I started it up and it ran OK, but still had a slight tendency to bog down. Put that bolt back in and it bogs down immediately. So I'm guessing it IS a carb problem after all, but I've had it for 9 years now, so not complaining. I'm also guessing that the time I took it to the shop because it was bogging down they removed the screen and gave it back after charging me $45. Found carb+air filter+fuel filter+spark plug+spare primer bulb combo on Amazon for $14.85 with free shipping.

[@cocacola3452]

My trimmer acted up yesterday. Found your video, removed the spark arrestor and trimmed the yard today. Thank you so much!

[@slick1591]

12 years later & your video still helps people out, it was the problem on 2 of these I got from a former employer stating "Throw them out, they don't run" guess what? I have 2 perfect running Stihl whips!

[@326CHARLIE]

Thanks! When a new carburetor, air filter and spark plug (Amazon special) didn't resolve my Stihl's sluggish running when I tried to get it up to operating speed, I had to change my search terms and I saw your video. So I removed the spark arrestor and the weed eater ran like new. And so many hours wasted trying to adjust the High screw on the carb! A cleaned spark arrestor was all it needed. My search term was "Stihl "FS38" how to adjust valves" because I had seen an earlier video where a guy reduced the clearance between the tappets and valve stems. I was looking for that! I'm glad google put you at the top of the heap. Have a nice day!

[@chrisj0]

10 years later and this is the video that helped me figure out the problem with my string trimmer... or as we used to call it "my weed whacker!"

[@ericlee8950]

We call it a Whipper Snipper in my parts

[@philtronmegabrew]

You sir are a legend my machine f38 was only 3 months old and all of a sudden stopped i did everything from carby clean, fresh fuel, and was about to throw it back at the salesman when i see this video and found my spark arrester blocked by a wasp larvae, 30 second unblock and it comes back to life first pull, thank you saved me a lot of grief and possible assault charges

[@donyboy73]

+Phildo Baggins lol, have a good weekend

[@bpd333]

I have a lawn business and my dad gave me his old trimmer, because it wasn't working. I changed the spark plug and cleaned the carb, but it ran really crappy like yours. I cleaned the screen and it's working great now. Thanks for the info!!!

[@Tellitasitis72Joe]

After an hour trying to get mine running right, Its now working gr8 after watching your video.. Ty

[@marcoandstephanie3976]

I pulled my trimmer out of my truck as I was going to take it out for repair. Took me longer to find my 15mm socket than it took me to get my trimmer to start. Thanks for saving me money on a repair. These seems like one of those easy repairs a small engine tech could use to soak you into a costly carburetor rebuild that was never done.

[@adreonjunkjunk4519]

Thank you! I couldn't figure out why my FS45 would bog down. I had taken apart everything and nothing worked till I saw your video. I followed your clear instructions, and BINGO, it runs great. THANK YOU!

[@jayg3559]

Just did this with my stihl F5 55RC weed wacker and it works perfectly now. The screen didn`t look that clogged , but cleaning it off made all the difference. Thanks

[@mystiksoldier]

I finally had to log in and leave a comment for you donyboy. I've watched many of your instructional videos and read a lot of your reply comments . I have to say that you've saved me tons of money by showing me the procedures and solutions to fixing many items. You're videos are very informative and you're presentation is of calm manner. I bow down to you and thank you kindly for all that you do and have done.

[@nedt]

If I could give you 100 thumbs up I would! I pulled appart the carby and was left scratching my head allot before watching your video. Thankyou you did a great job of explaining and demonstrating the fault and fix. Thanks again!

[@TheLintee]

Thank you so much for taking the time to show us this repair. This repair should be in the manual but the repair shops wouldn't be getting a $100 bucks to do it. Your awesome!

[@leestopps5565]

I took mine to the Stihl Dealer only yesterday with this problem and they stated $120 AUD to fix. I watched this and went and removed my FS38 from the repair shop this morning and its running like new again ... Thanks a lot for sharing your knowledge

[@juice1893]

Fixed my Stihl weed trimmer! Thank you for taking the time to upload this video.

[@Shaftell]

Thank you so much! Have the same model as you with the same problem. The manual says to clean the spark plug but that did nothing. Used a 15 mm socket wrench thing and took out the spark plug arrestor. Didn't have a blow torch or the wire brush so I used a lighter to burn off whatever was on there and used steel wool to brush the rest of it off. Popped it back in and the thing is running better than I could remember. Brand new really, I must've been using it at 50% power this whole time. Thank you so much man!

[@madelineparish2216]

Hello from Australia, Couldn't start the stihl, couldn't get it serviced before Christmas Googled your video. Thanks heaps, never thought of looking there.

[@donyboy73]

+Madeline Parish greetings from Canada

[@griffulance]

Thanks SO much for posting this! You saved me a trip to the repair shop. You're absolutely right, it was an easy repair. Cheers to you and have a great weekend. :)

[@Pudsy440]

Hello from Nova Scotia. After changing the spark plug and fuel filter, I was about to take my 2 yr old FS250 brush cutter to the repair shop who would have charged me who knows what ... I called them but it was late and they were closed ... so I did some searchin and found your vid. Thank you very much, the spark arrester was filthy and you saved me some $$! Runs like a top again.

[@donyboy73]

Pudsy440 you're welcome

[@sbark63]

Thanks for posting this. I installed a carb kit on my ECHO ES2400 shred 'n vac, and afterward experienced the same problems as your trimmer. Spark arrestor screen was clogged - once cleaned, it ran like a champ!

[@acthomson50plus]

Exactly my model, exactly my problem. Perfect solution, thank you!

[@halloweenstore]

I'd had been trying to start my FS250 for a few days. Saw this vid and instantly fixed the problem. Thanks a lot!

[@donyboy73]

make sure to subscribe

[@jaygreen1313]

Your description "gutless" was perfect. I spent the day farting around with my K55 and then just gave up trying to fix it. I found this video, cleaned the screen and it is running like new. A very simple fix. Thanks for saving me a trip to the repair shop.

[@sameguyever]

You the best man ,I was playing with my trimmer that won't stay on I clean the carb twice and nothing ,I saw your vid and fixed in 1 minute thanks a lot now I'm back to work 👍👍👍

[@rttreecare]

thanks saved me a ton of time and kept me outa the local stihl dealership saving me even more money!

[@coondam]

I have the same problem with my father in laws Stihl FS 46 weed trimmer! I tore apart the carb twice but it still only idles, any more trottle and it boggs down. I had plans to see if it has a rev limitor, but after watching your vid, i bet this is it. It drips oil when it hangs, which I was going to investigate too. Glad I saw your vid before I tore it apart to get to the coil! Thanks for the advise, your videos are great!

[@majsmith66]

I have spent hours stripping and cleaning my trimmer and rebuilding my carburettor to no avail, and no-one I know has even suggested cleaning the spark arrester. I didn't even consider it. Then I saw your video. I cleaned it and now it runs like a new one. Thank you very much indeed! Cheers!

[@donyboy73]

you're welcome, make sure you are subscribed

[@didge110]

Brilliant - first post I clicked on and you saved the day - fantastic, I owe you a beer! Many thanks.

[@teacher1172]

You are a legend. Thankyou I have cleaned the carb, changed fuel, sparkplug and have been ready to call the dealer. Thanks again the bloody thing was clogged as.

[@josephshideler1076]

Thank you! I was worried it was carburetor problems, but this fixed it!

[@woodfern]

I tried your tip today and was in shock how easy it was to do and how well it ran when I was done. 10 minutes and about $50 (local repair shop fee) saved. Thank you

[@KiRiMa64]

Awesome! Now I have no excuse to avoid the weed eating chores around my house! Thanks mucho!!! 2 thumbs up!!!

[@idokerpel5840]

This completely solved my issue on TWO trimmers!! Excellent, to the point video!

[@merely_scott]

Great video! I recently repaired a Stihl string trimmer where a mud wasp completely filled up the spark arrestor with mud. It was easy to clear it out with hot water.

[@marccampbell312]

ah thanks that was awesome, i was heading to the stihl shop in the morning after having played around and carby swapping etc today, that was brilliant, thanks again, marc

[@johnwebster1168]

Ditto... I have a Stihl weedeater and it was running sluggish and had no guys... or guttless as Donny Boy notes. Watched the vid, made the fix and bingo... she is running like a top! Thanks so much for posting this vid. Thanks... JW

[@landondale8496]

Thank you! This was exactly the problem on my FS55. Totally clogged. Brush wheel on bench grinder and some carb cleaner did the trick. Must have been a slow fade because after the cleaning this thing ran better than I remembered.

[@GianfrancoFronzi]

Donyboy , your the greatest , you just answered my problem, i've been working on my stihl all winter , and didn't think of this .

[@mannymanano]

Thanks for going through the trouble of showing the step by step procedure. There are a few videos on KZbin about this repair, although appreciated, it was not shown on how to do this. I will try this, as the repair guy I was going to use is sick and he told me to take the muffler apart and clean out the inside, as that may be the problem. The first thought came to mind, as I'm sure to many, is that it is a carb adjustment problem or it needs carb fix.

[@Mrtechsauce]

my Maruyama AE230 had the same problem. not as severe but it didn't have any top end. i took it out completely and it runs like new. thanks :)

[@cloudbud4313]

My man. Thank you for this video. You really saved the day for me. I never even thought about checking the exhaust. Thanks again.

[@johnvlooswyk4324]

Very useful info, even 10 years later. THANK YOU!!

[@chappy726]

I had same problem. My Stihl FS55 got weaker and weaker over the last few tanks of gas. I thought it was a lack of fuel problem as the engine would bog down if you gave it throttle. I did sound like it was bunged up too. As soon as I heard your plugged up engine I knew i had a fix. 10 minutes and running like new. Green mist everywhere. Thanks Dude!!!

[@chrisjr6942]

9 year old video but it really helped me today thank you

[@bthomastn]

Thank you for this video, I had the Stihl FS450 with the same problem after cleaning the spark plug, filter and carb to no avail. I googled the problem, watched the video, the cut filter off, and it runs as good as new. THANKS!!!!

[@markb3146]

Greetings from Australia to our Canadian cousin: Saw this video and the penny dropped on the cause of my lack of power when using the throttle. Went to the mower shop and bought a new one (AUD $15) , all fixed. I now have 2 to swap about. Donnyboy73 they did suggest an easier fix than using a wire wheel... ***** use a blowtorch if you have access to one and burn the clogged oil to ash ****** ..... i did just this and the original is now as good as new to swap for next time, all oiled up to stop rusting ... thanks again for the hard work on the videos

[@donyboy73]

+mark n kate bilston thanks, here's my updated video also in HD kzbin.info/www/bejne/i2Gve2adjZeSedk

[@wikkidme755]

If your just trimming around the yard, pull the screen off altogether and it will run twice as good. Same with my blower.

[@paulcarpenter7429]

Hello from New Brunswick. Thanks for the vid. Was exactly my problem. Was getting ready to buy a new one. Couldn't believe that all it was! Runs like the day I bought it.

[@donyboy73]

+Paul Carpenter greetings from Ontario!

[@eddieguerrero6845]

Awesome video saved me a trip to the shop and it works perfect

[@louisdupilka2870]

Donyboy73--YOU are da man saving me big bucks--thanks best small engine videos on the tube... Lou

[@donyboy73]

thanks Lou

[@packhead]

This worked for me! Thanks so much!! At least removing it let me run the thing. Now I'm hoping an overnight soak will clean the part sufficiently so that I can put it back. In the meantime, the trimming is done. I appreciate it.

[@donyboy73]

you're welcome and thanks for watching, I have a recent video in HD of this procedure

[@abcrystalclear]

Thanks Donyboy!!! Your fix worked like a charm!

[@ZaphodsPlanet]

Thank you so much for posting this video. I've got several stihl products (chainsaw, edger & trimmer). The edger (FC-55) I bought second hand and the other two I bought new. I bought it I think almost 3 years ago and never was very powerful. Over the past few weekends it was just near dead... no torque.... always stalling out...etc. Pulled the arrestor and cleaned it and OMG. it's like a new machine. More power than it's ever had. Feels like it will cut through concrete now...LOL

[@freedomearthmoon1]

THANKS, donyboy. I didn't know what was going on with my 8 year old FS46 trimmer.I changed the spark plug "probably a good thing". Cleaned the air filter and "Nothing". It still wouldn't rev up and work. Problem was intermittent for a couple of seasons. It would run bad for 3 min. and run great for a month afterward. Your video saved me and I thank you Very Much for that{: >)

[@davidplaisance1595]

thank you very much, love the way you show how machine is running then fixing the problem. please post more informational vid's in the future.

[@justrandallc]

Well Dony, found your youtube site a few days ago and you are my new hero. Great, great job. Best how to videos I've seen. Thanks for sharing your knowledge in such a perfect way. Thanks

[@lunoidlunonote1481]

Oh geez so glad i started on your video! Unfortunately my 2021 FS 38 needs to remove orange pull cover and then the revised spark arrestor. I tried with engine degreaser sos so results. Could also be the fuel supply.

[@omcd666]

Thank you for this video. I cleaned mine and now she sounds brand new.

[@randallantill8803]

NICE I am 50years old and partialy retired I have worked on various types of lawn equipment over the last few years for a few extra dollars .weedeaters and blowers for what ever reason I thought because of there size are a hassle to work on somtimes and just a pain in the butt, knowing that one little tip is gonna save me some head scratching help me put a few extra dollars in my pocket your Thanks for the video nice job

[@michaelgordy6283]

I just want to tell you what a Great Video! I thought it was the carborater or something i would have to send to the shop. Lord know I can't stand other people working on any of my stuff. This really helped out ALOT! And that was the problem. Thank you for saving money & time. I would also like to Thank You Tube for having information like this so people like myself can finish projects without the Headache of having someone eles charge me up the rear for something that anyone can really do. Again Thanks alot!

[@DandyDogsandCats]

fantastic, perfect video. instructions and video could not be better. After just one viewing we had the string trimmer back to where it was when new. thanks so much, Dony!

[@esobofh]

Thank you sir - you just saved me $200.00 - I rebuilt the carb with no luck. Thinking that I must have missed a clog or something, I rebuilt again! I didn't even think to check the muffler! The local equipment shop said I need a new carb, which was $90 - or just buy a new FS38, which was on sale for $150... But I was hesitant (Stihls are good quality and should last forever, right?!) - i pulled the spark arrester out (and just ripped the whole screen off) - she works better than brand new!

[@ddtisme40]

Awesome! I was just about to chunk this thing in the trash! Worked like a charm, in 5 minutes it was up and running! THANKS!

[@MattsRageFitGarage]

I've never seen a spark arestor like that before. thumbs up dude !

[@WOOODYII2]

As usual, great video Dony. Helped me out again. Watching all your videos is like a college small engine class..lol

[@soapsoilandsunshine3241]

Thanks so much for this. My Stihl whipper snipper has been very erratic with its revving, particularly when under load. Will give this a go before I look at dismantling the throttle/kill switch assembly - which was my first thought with this problem. It has a new carby kit installed recently. **Edit** Checked my spark arrester and it doesn't even have one. LOL. Will look into fixing the trigger mechanism.

[@johnd4307]

Thanks very much. I mucked around with the carby for a while but this was very helpful and much appreciated. Professional too! Thanks

[@kdleo71]

Thanks for the video. Cleaned using gas. carb cleaner, and a wire brush. Runs like a champ now.

[@donyboy73]

Great job!

[@gillesallain919]

had problem with my weedeater saw your video did what you instructed,rebuild the carb .I did not have the carb ajusting tool took my dremel mounted with a cutting weel made a natch on bolt ajusted it works fine now .thank you. gilles de pointe-calumet québec

[@dannypaningbatan9510]

Thank you for enabling me to fix my grass trimmer.

[@rustleshackleford1553]

Unfortunately im now checking it last, but hopefully this saved me a trip to the shop.

[@TheLincoln1980]

Just fixed my FS70RC with your info..........Thanks

[@donyboy73]

@Rarrin9378 it won't cause any damage if the spark arrester screen is out, might give u more power

[@Yoon9411]

Thanks for sharing this tip, worked great on our stihl trimmer.

[@donyboy73]

@erickafollie hi, i don't have one to make a video but make sure the switch is in the "on" position, turn the choke on, push the primer bulb a few times and pull until it starts and let it warm up. usually pressing on the throttle will turn the choke off. you can also go to a local stihl dealer and they should show you free of charge

[@donyboy73]

@coondam thanks for watching, hopefully this is your problem, i have other fs 38 vids

[@hippo-potamus]

Outstanding, you just saved me a bunch of repair money! Thanks

[@spiff2268]

Thanks for the video. This will be the next thing I look at. I hope that's my problem as well. Also, a video on how to remove that top cover so I can get at the spark plug would be pretty groovy.

[@SuperRealdeal45]

Man you're awesome! ! I watched this and was able to fix my weed eater

[@talimatatia8940]

Thank U... you really ease my stress.

[@j3ff337]

This was the perfect video. Exactly what I was experiencing and doing the exact procedure my weed whacked worked perfectly!

[@donyboy73]

+Jeffrey Lee make sure you are subscribed

[@MurphOOC]

This worked like a charm. Thanks! I’m pretty sure that would have helped me fix a blower I threw away a few years ago after trying everything else.

[@OlBlueshound]

You are a legend thanks for posting this.

[@RobsKoiPond]

Great video as mine is doing the exact same thing. Bogging down when it's first started. I pulled the muffler and it's clean. Lol I have no idea what the issue is. It's only 2 years old. Thanks for the video.

[@pakapewi]

Thanks heaps for this worked a treat for my fs 45 trimmer.

[@Cupracop]

I have the FS38 but there is no bolt on the muffler to remove the spark arrester. I've removed the whole muffler and it looks like a sealed unit. Any ideas?

[@jefftitus5178]

Thanks, you just saved me a lot of time and money.

[@kelmaddog]

Great job. Worked like a charm

[@eddieandrews3335]

Your a legend mate, thanks a bunch

[@elevatorman427]

gonna have to try this on my fs38. Its doing something similar to that right there if you keep fluttering and playing with the throttle it will eventually run as long as there is gas to it but, takes forever to get it going. If you let off for a few seconds even if warm then try to give it gas again it does it again and wants to die if I keep giving it gas. The oil I mix with gas contains a stabilizer and I don't think I have gummed up issues

[@ProductReviews937]

hi there mine has white smoke coming out of it and the power recently is getting weaker. I've replaced the carboraiter or however it's spelled in the past. Any suggestions before I spend $60 to service it?

[@jodystockley]

This worked like a charm. Thanks a lot!

[@hallhouse5098]

This may be my problem on my FS 55 as I noticed a burning smell and my muffler was red hot and melted a lot of the surrounding plastic. It wasn’t running well at all prior to that but it seemed to pick up gusto briefly if I pressed the primer bulb.

[@brumasbusiness]

Hi just a suggestion. I run a lawn care business and I have to clean every month or month and half this screens and what I do is, burn. Yes I burn with a small torch then I just blow with the air compressor and job done, its a 3 to 5 minutes job. (we are always learning)

[@SoldotnaUMChurch]

Great advice, this fixed my problem. thanks.

[@darrinanddonna]

thank you for the info !! I tried this on my husky trimmer and problem is now fixed ! thanks again A+++

[@donyboy73]

you're welcome Kylie, greetings from the top of the earth!

[@jerometetreault8351]

hey thanks a bunch. had brought my fs55 to john deere for repair and his advise was to buy a new one. after carb cleaning no results. once i watched your video bingo. leaf cutter bees had filled my spark arrest and could not make it run. now it runs like new. thanks

[@donyboy73]

jerome tetreault good for you!

[@juf2003]

Thanks for the video! very useful! I was trying to remove the spark arrester but it seems in my Stihl FS38 the spark arrester is fixed and sealed. It doesn´t have any movil piece. I am lost at this point.