STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???

Flatsix

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Hello,

I bought last year 2 hedgetrimmers STIHL HS82 - the "T" and the "R" version. They do good, only I see and hear that 1 of them, the "R" is running too rich because fumes , sound and more oil coming out of the exhaust.
I went to 2 Stihl-dealers here, but both don't seem to be able to adjust the machine as I wish.
I checked how many turns the "H"-sscrew was screwed out on both machines. The "R" had 2.5 turns out and the "T" had 2.1/8" turns out.
I have set the H also at 2.1/8" on my "R"-type and thought that then they would be the same, but I see that the "R" is still running too rich.
Then I asked STIHL-Belgium what the factory settings are for the hedgetrimmer HS82, they replied: turn H and L-screw both 1.1/2 turn out. Then turn the rpm on the L-screw as low as possible and the H-screw as high rpm as possible.
I know that the HS82 has a speed-limiter (9300 rpm) - so when I turn the H-screw it is difficult to hear because of that speedlimiter. I have also a tachometer.
Can somebody explain to me HOW I CAN SET THE H-screw CORRECTLY ON MY 2 HEDGETRIMMERS HS82. Both machines are the same when you only compare the motor. I can use my tachometer eventually.

HOW TO DO IT ??

Thanks for your technical advise.
 

Flatsix

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Read Operators Manual thoroughly, should be under warranty take to reputable Stihl Dealer. Use 90 octane gasoline minimum plus Stihl 2-cycle oil.
Operators Manual does not mention anything about the settings of the "H" screw. It says only that the machine is set in the factory for optimal results.
I do not know any "reputable dealer" - there are already 2 of those stihl-dealers that played with the settings, but none of them are good. That is why I wanted to do it myself instead of letting it do by another dealer.
I have 6 Stihl-machines and they all get the best : 98 Octane and the Stihl full synthetic 2-cycle oil (HP ULTRA).

Can anyone tell me exactly how to make the fuel/air mixture like it should (H-screw).??
 

Fish

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
The unit is newer, so I don't have any service manual.
But in general, just as a test, take off the air filter and start. See if the performance changes any.
If so, was the air filter if it is washable, or get a new one.
I have seen folks pull their hair out, and their trouble was a dirty air filter.
As far as any help on adjustment, I would need to see a pic of it, the side with the adjustments.
If it has limiter caps, there is very little range you can adjust it.

But do the air filter test first, see if the trimmer runs differently.
 

Fish

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
It looks like you may have limiter caps like this.
carbadj.JPG
 

Fish

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Here is the next page.
carbadj2.JPG
 

Flatsix

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Thanks Fish for the pages you showed. I do not have limiter caps on the machines - the airfilter is clean and as new and nice as a brandnew machine.
The STANDARDSETTING of the "H"-screw is 1.1/2 turn OPENED; this is the same as the people of STIHL-Belgium wrote.

But from 1.1/2 turns out to the optimal setting to have the right mix air/fuel : that is my question. HOW TO DO THIS TO OBTAIN THE RIGHT MIX AIR/FUEL by adjusting the H-screw.

At present both machines their "H" screw have I set to 2.1/8 turns out. I did so because my T-version was set on 2.1/8 out. The other was set at 2,5 turns out and I changed it to 2.1/8 - but for me still to rich....

HOW TO ??
 

Flatsix

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
At the end both of my machines HS82 work fine , the T-version sounds a little leaner and the exhaust is less greasy (or oily...) and produces less fumes when full throttle. The other one , the R-version works great but a little more oil at the exhaust + more fumes, but it sounds and works great.

If only I got to know from one of your specialists how to fine-tune that H-screw on each machine individually so that at full throttle I would have exactly the good mixture air/fuel then I would be happy. If not then I leave it like it is because I have no intention at screwing up my machines by turning without any procedure.

Can anyone tell me how the fine-tuning is done : I have no limiter caps on it, I have the special Stihl octogonal screwdriver and I have a tachomter in my possession, so with these I should be able to finetune if I get a procedure or a way to do it from you folks.
 

StarTech

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Okay you do need the Tach as going by ear just don't cut it.

Both the T and R are adjusted the same; unless, you have a Brazil setup which is slightly different on the R.
1696420649325.png
And I assuming the throttle cable has not been removed and reinstalled or otherwise messed with.
 

Tiger Small Engine

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  • / STIHL hedgetrimmer HS82 T and R : carburator "H" screw setting???
Okay you do need the Tach as going by ear just don't cut it.

Both the T and R are adjusted the same; unless, you have a Brazil setup which is slightly different on the R.
View attachment 66914
And I assuming the throttle cable has not been removed and reinstalled or otherwise messed with.
It takes years to be able to tune handheld 2-stroke equipment efficiently and effectively by ear and using a tachometer. Not something you can read and just turn a screw. Some are easier than others.
 
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