Stihl TS 800 Carburetor (Factory Setting Guide)
The TS 800’s carburetor does not have one safe screw-turn setting for every machine. Identify the serial number and carburetor first, then use the matching STIHL service procedure. The published baseline includes 50:1 fuel, a 2,500-rpm idle speed, and a 9,300-rpm maximum spindle speed. Confirm these values in your machine’s manual before adjustment.
A carburetor problem can look like a carburetor problem even when the cause is stale fuel, a blocked filter, or an air leak. That is the paradox: turning adjustment screws may make the saw run differently, but it can also hide the fault and raise the risk of engine damage.
I treat adjustment as the last step, not the first. The TS 800 is a cut-off machine, not a chainsaw, so chainsaw bar, chain, and oiling settings do not apply. Use the steps below to check the machine, find the correct factory baseline, and decide when dealer service is the safer choice.
Identify the TS 800 and its carburetor
Identification means matching the machine’s serial number and installed carburetor to the STIHL service information for that version. Parts and carburetor revisions may differ. A setting from another TS 800, even one that looks similar, is not a reliable factory baseline.
Before touching an adjustment screw, record the serial number from the machine and identify the carburetor type. Check the owner’s manual and obtain the matching STIHL service procedure. If the carburetor has been replaced, its part number may also matter.
There is no safe universal instruction such as “turn the H and L screws out a set number of turns.” Do not assume a generic online screw count applies. Do not force a screw against its seat, remove or defeat limiter caps, or open a sealed adjustment just to make the engine run.
| Check | What to confirm | Why it matters |
|---|---|---|
| Machine identity | TS 800 serial number and model | Service instructions can vary by version |
| Carburetor | Type or part number, if available | Different units may use different procedures |
| Adjustment access | Whether the procedure permits adjustment | Some settings may be restricted |
| Service data | Correct STIHL procedure for this machine | Prevents using a mismatched baseline |
If you cannot confirm the carburetor and procedure, stop at inspection and basic maintenance. An authorized STIHL service dealer can identify the correct parts and setting.
Check the machine before tuning
A pre-tuning check means inspecting fuel, air, ignition, exhaust, and controls before changing carburetor settings. These parts affect how the engine runs. Correcting a clogged filter or fuel-delivery problem first can avoid a needless adjustment and reduce the chance of running the engine lean.
Work outdoors with the machine cool and secured. Remove the wheel only as directed in the manual. Inspect the air filter, spark plug, fuel lines, tank cap, muffler, and spark arrestor. Look for damage, blockage, loose connections, or signs of fuel leakage. Service or replace parts according to the manual.
Use fresh fuel mixed at the specified 50:1 gasoline-to-two-cycle-oil ratio, with suitable high-quality two-cycle oil. That is 2 percent oil by volume: for example, 100 milliliters of oil for 5 liters of gasoline. Follow the manual and oil maker’s directions, and do not use straight gasoline.
Also inspect the wheel and its mounting parts. Use only a wheel approved for the TS 800, with the correct diameter, arbor, material, and maximum speed rating. The published maximum wheel diameter is 400 mm (16 inches); the published maximum cutting depth is 145 mm. Confirm both on the machine’s own documentation.
The machine’s specified figures include a 98.5 cm³ displacement, 2,500-rpm idle speed, and 9,300-rpm maximum spindle speed. These are reference specifications, not permission to adjust by guesswork. Verify them in the manual or service data for your serial number.
Follow the correct factory-setting procedure
A factory-setting procedure is the model-specific sequence STIHL provides for checking or adjusting the carburetor. It may require a warm engine and a tachometer, a tool that measures engine speed. Use the procedure only after confirming it applies to the installed carburetor.
- Prepare safely. Work outdoors on a cool machine. Wear the manual-specified eye and face, hearing, hand, leg, and foot protection. Set the machine on a stable surface, keep bystanders clear, and control dust.
- Complete the inspection. Confirm that the wheel is correctly installed and undamaged, the guard is secure, and the throttle lockout and stop switch work. Resolve fuel, air-filter, exhaust, or ignition problems before tuning.
- Use the right fuel. Fill with fresh 50:1 mixture. Follow the starting and warm-up directions in the manual; do not tune a cold engine unless the service procedure specifically says to.
- Apply only the matched procedure. If adjustment is allowed, begin at the factory baseline stated in the correct STIHL service data. Make only the specified changes, using the stated tool and measurement method.
- Measure and verify. Use a tachometer if the procedure calls for one. Set idle to 2,500 rpm only if that value is specified for your machine. Confirm stable idle, clean acceleration, and no wheel rotation at idle. Observe the manual’s maximum-speed limit; the published maximum spindle speed is 9,300 rpm.
- Stop if the result is wrong. If the engine races, runs unevenly, cannot hold idle, or exceeds the specified speed, shut it down. Do not keep compensating with screw turns.
The wheel must remain still at idle. If it turns, stop the engine and do not use the saw until the cause is corrected. A moving wheel can indicate an idle or clutch-related problem that needs proper diagnosis.
Read symptoms without guessing at screw settings
A symptom is a clue, not proof that the carburetor needs adjustment. A hard start or poor acceleration can come from several faults. Use the table to choose a safe next check, not to justify changing mixture screws without the correct service data.
| Symptom | First checks | Safe next step |
|---|---|---|
| Hard starting | Fuel age and mixture, starting method, spark plug | Follow manual checks; inspect fuel and ignition parts |
| Engine starts, then stalls | Air filter, fuel lines, tank cap, fuel quality | Correct blockage or damage before carburetor work |
| Weak acceleration | Air filter, exhaust or spark-arrestor blockage, fuel delivery | Service parts at manual intervals; then reassess |
| Unstable or high idle | Air leak, fuel delivery, carburetor condition | Stop if speed is high or wheel turns; seek service |
| Speed cannot be set to specification | Carburetor version, mechanical condition, service procedure | Do not continue tuning; contact a dealer |
An air leak means unwanted air enters the engine, changing the fuel-air mixture. A lean condition means there is too much air, or too little fuel, for safe operation. A lean engine can overheat and seize; incorrect adjustment, restricted fuel flow, stale or incorrectly mixed fuel, or a leak can contribute.
Do not tune by ear. A sound that seems smooth does not confirm that engine speed is within specification. Do not use the adjustment screws to cover up a clogged filter, damaged fuel line, or other mechanical fault.
Field scenarios: what to check before adjustment
These scenarios show how to apply the checks in practice; they are diagnostic examples, not claims about a particular repair or documented customer case. The key point is to separate a fuel or maintenance fault from a carburetor-setting issue before changing the baseline.
Scenario: the saw starts after several pulls, then fades. I would first check whether the fuel is fresh and mixed 50:1, then inspect the air filter, fuel lines, and tank cap. If the fuel system is restricted, changing carburetor settings can mask the symptom without fixing its cause. Follow the manual’s tests and service intervals.
Scenario: the wheel creeps or spins at idle. Shut the engine off. Verify the idle procedure and specification for the serial-number range, but do not continue operating while the wheel moves at idle. If correct service steps do not resolve it, have a qualified technician inspect the machine.
Scenario: the engine races after a carburetor change. Stop using it. Confirm that the replacement carburetor is correct and that the adjustment procedure matches it. High or unstable speed can signal a setup error or an air leak. Do not run the machine to “see if it settles.”
In each case, the order is the same: identify, inspect, correct known faults, and only then use the matched adjustment procedure.
Maintain the carburetor and prepare for storage
Routine care means keeping air and fuel paths clean and using fresh, correctly mixed fuel. It helps the engine start reliably, but it does not replace the serial-specific carburetor procedure. Use the intervals and methods in the TS 800 manual rather than relying on a general schedule.
Clean or replace the air filter, and service the fuel filter and spark arrestor as directed. Inspect the wheel for cracks, damage, wear, and the correct speed rating. Never use a damaged or incorrectly rated wheel. Keep the guard in place and working.
Before storage, empty or stabilize fuel as directed in the manual. Stale fuel can make starting difficult and harm fuel-system parts. Store the machine in a cool, dry, secure place, with the wheel protected from impact and moisture. Let the machine cool before cleaning or storage.
Do not operate with straight gasoline, a damaged or incorrect wheel, a disabled guard, or a wheel that continues turning at idle. If the factory setting is uncertain, limiter parts are damaged, or adjustment would require opening a restricted setting, obtain the right STIHL service data or have a dealer handle it.
Key takeaway
The right factory setting is the procedure for your TS 800’s serial number and carburetor, not a generic H/L screw count. Confirm the machine’s condition and fuel mix first. Use a tachometer and the specified steps when adjustment is allowed, and stop if idle, wheel movement, or speed is outside the manual’s limits.
Frequently asked questions
What is the factory carburetor setting for a STIHL TS 800?
There is no single safe screw-turn count for every TS 800. Identify the serial number and carburetor, then use the matching STIHL service procedure.
What fuel mixture does the TS 800 use?
The specified mixture is 50:1 gasoline to two-cycle oil. Confirm the fuel directions in your machine’s manual and use fresh, properly mixed fuel.
What is the TS 800’s idle speed?
The published idle-speed specification is 2,500 rpm. Verify that it applies to your serial-number range before adjusting.
What is the maximum spindle speed?
The published maximum spindle speed is 9,300 rpm. Use the correct service procedure and a tachometer when required; do not estimate speed by sound.
Should the wheel spin at idle?
No. The wheel should not rotate at idle. Shut the engine off if it does, and correct the cause before using the machine.
Can I use a generic H- and L-screw setting?
No. Carburetor versions and service procedures can differ. Do not apply a generic turn count or force screws against their seats.
Why does my TS 800 stall after starting?
Possible causes include stale or incorrectly mixed fuel, a blocked air filter, a restricted fuel path, or another mechanical fault. Check these before considering carburetor adjustment.
Can I adjust the carburetor by ear?
No. A smooth sound does not prove the engine is within its speed limits. Follow the applicable service procedure and use a tachometer when specified.
What wheel size fits the TS 800?
The published maximum wheel diameter is 400 mm (16 inches). Confirm the correct wheel type, arbor, and speed rating in the machine’s manual.
When should I use a STIHL dealer?
Use an authorized dealer when the carburetor version or setting is uncertain, limiter parts are damaged, speed is unstable or excessive, or the engine cannot be brought within specification.
(This article was written by one of our staff writers, Harrison Croft. Visit our Meet the Team page.)
