Was at a friends today helping out with some renovations. I had also promised him to look at the FS 45 trimmer he has which I did but it started getting too late and dark by the time I got to it for me to be able to have much of a look at it. He had told me it was hard to start and running like crap with lots of white smoke. I managed to get it started and sure enough it was running way too rich so I turned down the mixtures which made it run a little better but not enough rpm to have any sort of power to get through weed. I noticed it even ran with the H mix bottomed out still puffing smoke. Any ideas what could be causing this? I did think choke but it appears to be operating ok. He didn't have the right screwdriver to get the cover off so could not check anything.
STIHL FS 45 - advice needed (1 Viewer)
- Thread starter rockcrawler
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Did he mix the gas correctly ?? Too much oil in the gas can cause that kind of problem.
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- #3
As far as I know Weedhopper, but that's something I am going to have to confirm by refueling it before taking it apart. I also asked him when the last time was he cleaned the air filter and the answer was "what air filter?" so.... yeah 
Doubt if it's that though as trimmers don't usually suck up that much crud.
Doubt if it's that though as trimmers don't usually suck up that much crud.
Yep
Remove the spark arrestor in the muffler. It is probably plugged. Mix some fresh fuel at the correct ratio and the unit will probably run fine.
Remove the spark arrestor in the muffler. It is probably plugged. Mix some fresh fuel at the correct ratio and the unit will probably run fine.
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- #5
Ok thanks to both of you. Will do that and report back with how I go with it.
I never use another mans gas..............................
We have had a couple of tree takedown parties here at the house. A friend wants the wood and I want the trees gone. I always tell my sons "use my gas" you never know how someone else mixed it. Too rich is a pain, too lean means you buy a new saw.
We have had a couple of tree takedown parties here at the house. A friend wants the wood and I want the trees gone. I always tell my sons "use my gas" you never know how someone else mixed it. Too rich is a pain, too lean means you buy a new saw.
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- #7
That's a good policy Weedhopper.
This one has me a bit stumped, haven't had a chance to go back there yet but the story is that the "fuel is not bad". He is quite adamant that he is meticulous when it comes to mixing his fuel, even has a mixing cup etc. What's perculiar is that he also has a stihl blower that's get fed out of the same container and that it apparently has been running with that fuel with no problem. But like you say, with some things its best not to take anybody's word for it. Gonna take a can around to save any argument and hopefully that will be it, don't need another project right now
, bits of cruiser all over the garage, also making up a couple of new benches in there and re-arranging the space so its a bit of a mess.
This one has me a bit stumped, haven't had a chance to go back there yet but the story is that the "fuel is not bad". He is quite adamant that he is meticulous when it comes to mixing his fuel, even has a mixing cup etc. What's perculiar is that he also has a stihl blower that's get fed out of the same container and that it apparently has been running with that fuel with no problem. But like you say, with some things its best not to take anybody's word for it. Gonna take a can around to save any argument and hopefully that will be it, don't need another project right now
, bits of cruiser all over the garage, also making up a couple of new benches in there and re-arranging the space so its a bit of a mess.
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Stupid me.
I didn't realize you were from Australia. Turn it upside down and you will be fine.
I didn't realize you were from Australia. Turn it upside down and you will be fine.
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- #9
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- #10
Ok so it was the fuel. We suspect his son (the last person to use it) mixed the fuel in the fuel tank directly. Cleaned out the spark arrestor in the muffler and yep there was quite a bit of crap in there. All good now.
Congrats!
