Export thread

I have a KM130R that I put a new carb on. Of course the new carb needs to be adjusted but I can't figure it out. There are so many different ways according to the Net so I wanted to reach out here.

Just couple of questions

where do I start the high and low speed screws?

Do I adjust with or without an attachment on the motor?

Thanks I greatly appreciate you advice/help.


James

All hand helds a tuned under load.
And if he repairer realy knows what they are doing they work to tool and make the final adjustments with the tool under working loads.
You start with the High as that is where you use the tool.
Once the H is set, you adjust the L to work with it.
Then you go back to check the H as changing the L may have altered where it needs to be
then the L again.
Once here you then adjust the idle speed throttle stop.
Then go outside and use the tool screwdriver in pocket.
When finished readjust the L to work with the H and if needed the idle again so that the tool head does not rotate.

bertsmobile1 said:

All hand helds a tuned under load.
And if he repairer realy knows what they are doing they work to tool and make the final adjustments with the tool under working loads.
You start with the High as that is where you use the tool.
Once the H is set, you adjust the L to work with it.
Then you go back to check the H as changing the L may have altered where it needs to be
then the L again.
Once here you then adjust the idle speed throttle stop.
Then go outside and use the tool screwdriver in pocket.
When finished readjust the L to work with the H and if needed the idle again so that the tool head does not rotate.

Click to expand...

Where do I start with the high and low screws?

Thanks

James

between 1 & 2 turns out.
try a few pulls with the choke on that loads up the system with fuel if it does not start.
Next hold the trigger WFO , choke off, and usually it will start up.
keep the throttle WFO while you adjust the H needle, in= lean till the engine starts to miss then out + rich till again it starts to miss then back to slightly rich of 1/2 way between the two faulter positions.
Slowly release the trigger.
If you can let it off fully, good luck and do the same with it as the H needle.
If it starts to faulter as you are letting it off adjust the L needle accordingly remembering the different sounds the H needle made as you went from too lean to too rich.

Repeat for both needles, then slowly throttle on from idle
If the engine stumbles going from idle to WFO then adjust the L needle to remove the stumble, usually you need to lean it off a little.
Adjust the idle speed
Now go out side & use it.

Hey Bertsmobile1, jus fyi you were dead wrong about the positioning of the H & L screws. I tried your suggestion above and to be honest it seemed like it was also everyone's oppinion and could not get it work it would not start, it would not idle, but it would run at full out. Out of frustration I figured I'd just take it in to get it serviced. Never being one to give up I searched online and managed after some effort to find the "STIHL Series 4180 powerhead" manual and it stated turn the H out 4 and the L 2 3/8 turns ( yes 2 3/8 ). I tried that and BAM! It ran like new. I had to adjust the idle to 2800 rpm and now it works perfectly.

According to the manual the H & L

FS 90; FC 90, 95; KM 90: H 1 turn, L 3.5 turns
FS/FC/KM 100, 110; HT 100, 101: H 2 turns, L 3 turns
FS/KM 130: H 4 turns, L 2 3/8

All the above are from just seated out clockwise

Also idle should be set to 2800 rpm.

Never more happier to be proven wrong, cause from now on will be right.
Sorry for the bum steer
It should have started on 2 turns, which it did , These are just initial settings enough for it to start , from then on you have to be able to understand what you are hearing.
That is the difference between people who do it every day and can hear what the engine is telling them .
There is big difference in the sound of an engine starving verses choking
I was using old Stihl tech information.
The wider openings are for the newer compliant engines.

Glad to hear you got it running, another one to add to the errata list.
I ignore recommended idle speeds which are hard to measure accurately in any case.
Like most techs, it is sounds and feel.
Must be slow enough for the impliment to stop moving yet fast enough to respond to the trigger instantly and accelerate smoothly without stutter or hesitation.

Numbers are there for the calculator generation and usually are +/- 300-500 rpm.
Same with max rpm,
The numbers on the tacho can be right and the engine can still be running too lean or too rich and ultimately do damage to the engine