Stihl FS 131 R - Brand New From Dealer - Doesn't Work!

Ryan808

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
For the last 3 1/2 years I have used a Stihl FS 91 R that I purchased from a local dealer here in Hawaii. I started having trouble with it the last several uses. I tried multiple times to DIY Fix it but was unable to repair it successfully. I figured that to take it to a dealer and have it repaired could take a month or so and cost nearly half or more the cost of a new FS 91 R. After going back and forth mentally; I hated to replace it because it seemed to be something simple but I could not fix it and needed to weedeat so I finally just decided to buy a new one.

I went to the same dealer this last Saturday 10/09 (it is Monday now) and looked at 3 different models, another FS 91 R, a FS 111 R and a FS 131 R. I had looked at a Stihl Comparison PDF before going and had it on my phone. The FS 91 R is 28.4cc and the FS 131 R is 36.3 cc. I decided to purchase the FS 131 R trimmer. It came with an 'Auto Cut' trimmer head or the kind where two trimmer strings are wound into a spool and put into the trimmer head, you bump the head to advance the string as it is you are trimming and more of the line comes out of each side. I have never had good luck with this style of trimmer heads. On my FS 91 R I had what Stihl calls a 'Fix Cut' head. With this you use pre cut lengths of trimmer line and then feed it in manually. Each line is fed through the trimmer head where it goes in and back out, you have 4 equal lengths of your trimmer line coming out at the end trimmer head. When I purchased the FS 131 R I asked and I was able to purchase an additional trimmer head. I purchased the Weedeater and they took it into the back and put in about half a tank of gas and switched out the trimmer head.

Once I got home with the weedeater I started to weedeat immediately. First I put in some of my trimmer line from my old FS 91 R. The trimmer line, I bought a huge roll of 500' of .155 square line. It is flourecent orange. I bought it at the same dealer about a year or more ago. Immediately the new FS 131 R would not work right. I noticed an array of issues. First the choke, where you turn the knob, this knob is turned to engage the choke. This knob about half the time when you turn it you can feel resistance as you turn it and it squeaks kind of. When it does this the choke stays on even after pulling the throttle. By design it is supposed to automatically disengage the choke once the throttle is pulled. This one for some reason, it sticks sometimes. Also, the weedeater, you can start it and then get it to full throttle for about 15-30 seconds at a time at the most. After this it starts to bog down. You can hear the engine start to struggle, as if it were trying to go up a big hill but having trouble making it. When the engine is bogged down in any way it effects the speed of the trimmer head where you are cutting grass. If the trimmer head is not spinning at full speed or very near it it just twirls the grass around, tickling it kind of; not cutting it as it should. My old weedeater, when in use I would often run it at full speed for an hour or more straight. As long as you kept gas in it; it would run. That is how most working weedeaters work.

I kept tyring with the new weedeater, I found that it kept bogging down. It would bog down randomly and on it's own. Sometimes even when you would have the throttle all the way pulled in, it would clearly not be at full throttle or speed as it should be. If you let off the throttle suddeny or quickly as one would when in use the engine would not idle but would just die out. Sometimes if you slowly babied off the throttle and kind of kept giving it a bit of gas slowly over a period of time that it would start to idle. Very occasionally and randomly, if you would let it idle for a couple or few minutes and then slowly tried to go back to full speed it would work for about 15-30 seconds at the most and then would begin to bog down again. On the day that I bought it I spent 3.5 hours total messing with it. I only was able to actually weedeat as it should work for a total of about 5 minutes, I was able to weedeat one line along a 20' fenceline in 3.5 hours. When the engine is operating at full throttle and trimmer head are at full speed it makes a very obvious sound, you know that it is at full speed. Because of this you also know when it is not at full speed. It is audibly clear when the engine is struggling and obvious when the grass is just twirling around. As I said; I was only able to get it to work at full speed for 15-30 seconds at a time and very intermittently. My old FS 91 R I could run all day at full throttle as long as I kept gas in it, even using the same trimmer head and line!! I hadn't put any gas in it, the only gas that had been put into it at this point is what the dealer had put in. It ran out of gas from me messing with it on Saturday 10/09 (the day that I bought it). I decided to quit messing with it and not put any more gas in it. My thinking was that I would try to somehow return it or take it back and if I put in my own gas that adds more variables where the dealer could question me or the gas that I used, if it was the right kind, mix or if it was stale or old. I figured not putting in my own gas at all was the safest move I could make. I cleaned up the trimmer and cleaned all the grass off of the trimmer head and grass deflector the best that I could and put it in my garage. The next day the store was closed, it was Sunday. On the following Monday my partner called them. They told us to bring it in. We did and they took it in the back and looked at it very briefly. The fix cut head that I purchased was still installed and it had some of my .155 line from where I had tried to use the weedeater on the day I bought it.

They took the trimmer in the back of the shop and came out a few minutes later and said that the trimmer line was too big. They sold my partner a reel of .105 line and said for us to use that. They said that this was all that was wrong with it. My partner brought it back to me and told me this and I got extremely upset. This makes absolutely no sense to me. I had purchased the fix cut head. I have never used any line that was smaller than .130 or .155 with this kind of head. Using any smaller kind of line there isn't really even a need for the fix cut head, the head dwarfs the line like it just looks undersized. Aside from all this, as I said, my old trimmer is a FS 91 R. With the FS 91 R I have used this same exact trimmer head and trimmer string for the last 3.5 years. This new FS 131 R trimmer, it is essentially the exact same trimmer as the FS 91 R, they are designed exactly the same and use many of the same parts, the FS 131 R is just 8cc's or roughly 20% more powerful. Based on that fact alone using the FS 131 R I should be able to use the same string as I have been using. It should work and even with 8cc's or 20% more power than my old FS 91 R. The dealer is basically trying to say there is nothing wrong with the trimmer but I am limited to using this .105 string at the most. To me that is complete nonsense and if that is the case I want to get my $700 back!! I bought the Trimmer, the additional fix cut head and then a 6 pack of oil and it was just under $700. I have cane grass that I need to cut that is often waist height and I live in a tropical rainforest. Trying to cut the stuff in my yard with the .105 string feels like a joke to me after using the .155 for so long. I bought essentially the same trimmer as my old one but one with a 20% more powerful engine. I need a trimmer that works as good as my FS 91 R did and then some. This model should be exactly that and so far it has been nothing but a huge pain for me.

We did call Stihl today and talked with their customer service. Right now they are esclating the issue with a higher level of customer service. I said that I either wanted to have the unit (Trimmer) replaced entirely with another unit or I want a refund. She said that they would get back to me within 2-3 days and let me know what kind of options I have. Does anyone else agree that the dealer is giving me the run around about this? I cannot imagine using .105 string on the thick cane grasses that are in my yard. I live in a tropical rainforest and there are many invasive plants and dense tropical plants. If you do not weedeat very thoroughly every month or so it will begin to take over parts of your property. Buying this new, more powerful weedeater should be an upgrade for me over my previous trimmer. I bought a new trimmer that is 20% stronger but the dealer is telling me that I must use line that is ~30% smaller than what I was using? Makes zero sense to me and I think that this unit just has some kind of mechanical issue with the motor.
 

Tiger Small Engine

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
You wrote a novel.
Take new trimmer under warranty back to the dealer and get it repaired. If you don’t like that dealer, take somewhere else.

The Stihl FS91 is a great trimmer. Get it fixed as well at some point and then you have a back up.
 

Fish

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Did you remove the trimmer shield?
 

Ryan808

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Did you remove the trimmer shield?
The orange grass deflector shield? No I didn't, it is still in place from the factory or dealer. When I got it I put in the string and cut it to length where it was just short of the metal cut off on the underside of the shield.
 

Fish

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
The orange grass deflector shield? No I didn't, it is still in place from the factory or dealer. When I got it I put in the string and cut it to length where it was just short of the metal cut off on the underside of the shield.
OK, they will void the warranty if the shield has been removed.
Call the distributor yourself, and ask to talk to the salesperson for your area.
stihl haw.JPG
 

StarTech

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Well according to following if you have a Auto Cut 36-2 you should be able go up to .130 but no head listing using .155 string. And delaer is right too as depending the Auto Cut as several of them only goes to .105.
1696963112065.png
 

Ryan808

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Well according to following if you have a Auto Cut 36-2 you should be able go up to .130 but no head listing using .155 string. And delaer is right too as depending the Auto Cut as several of them only goes to .105.

I see that but still do not understand. On my FS 91 R, I have used a Fix Cut head with .155 string for the last 3.5 years.
On that sheet you posted, it says 'Light Grass Trimmer Heads' which I also don't understand. The grass I need to cut with the trimmer I would not consider to be light.
The grass I need to cut.. it is very thick and dense. Literally it is the jungle. Parts of it are cane grass and bamboo orchids and other tropical plants. I have managed to clear these areas of my yard the last 3.5 years using a FS 91 R, a Fix Cut Trimmer Head and .155 string. I understand that the .155 is a bit heavy and would be willing to do down to .130 at the least but to go down to a .105... that is just kind of an insult. If it is true that I can only use .105 string on this trimmer I am going to try to get a refund immediately. My FS 91 R would do it all day without issues when it was in it's prime. This FS 131 R is essentially the same unit but with 20% more power. It should do what my FS 91 R did with 20% more power, not I need to reduce my string size by 30% for the FS 131 R to even work.
 

Tiger Small Engine

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Talking to the distributor sales rep is the quickest way to get any results.
Take Fish’s advice.
.105” line is all you need. Go for the twisted, or square design, anything except round. It cuts better than the round stuff. The thicker diameter trimmer line slows down the head, not good. All of my trimmers have the guard removed, just like you see the commercial lawn guys do. Never burned up a clutch or engine as a result.
 
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StarTech

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  • / Stihl FS 131 R - Brand New From Dealer - Doesn't Work!
Personally I would switch to a bush blade setup on that heavy stuff. Even one with chainsaw cutters. I got weeds here that just eats the .150 line for dinner on walk behind trimmers.
 
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