Q: How to adjust the idle of the STIHL RM 650 VS engine?

The manual for the STIHL RM 650 VS does not include a section dedicated to adjusting the engine idle. This is not considered a standard maintenance adjustment that the user can perform themselves. Why? The idle is a very specific parameter of this 4-stroke engine. An incorrect adjustment can affect starting, fuel consumption, and the overall reliability of the machine. What you can check: Oil level - refer to the section Before each use in your manual Fresh fuel - use unleaded gasoline and check the recommended oil mixture Clutch/brake - test several engagement/disengagement cycles to ensure the engine does not stall If the engine stalls at idle or shows other anomalies, contact an authorized STIHL dealer who can diagnose and adjust the engine parameters if necessary.

Q: Which batteries and chargers are compatible with the STIHL RMA 448 VC?

Authorized batteries: The STIHL RMA 448 VC is powered exclusively by lithium-ion batteries from the STIHL AP series (36 V). Three models are compatible with this mower: AP 100 : maximum mowing speed 3.0 km/h, ideal for small areas AP 200 : maximum mowing speed 3.7 km/h, versatile use AP 300 : maximum mowing speed 4.5 km/h, for large areas Recommended chargers: Three STIHL charger models are compatible with all AP batteries to recharge your mower: AL 101 : compact and lightweight charger AL 300 : versatile mid-range charger AL 500 : high-end fast charger Charging times: Charging times vary depending on battery capacity, charger model used, ambient temperature, and initial charge state. For exact durations based on your setup, refer to the charger manual or visit www.stihl.com/charging-times. Important recommendations: Use only approved original STIHL batteries and chargers for this mower. Non-STIHL batteries can be dangerous (fire or explosion risks) and void the warranty. Store batteries at temperatures between -10 °C and +50 °C, and keep them clean and dry. For maintenance or repairs, contact a specialized STIHL dealer.

Q: How to set the working radius on the STIHL iMow RMI 422 mower robot after defining the starting point?

The STIHL iMow RMI 422 PC mower robot allows you to set a working radius around the starting points , between 3 meters and 30 meters . This radius is defined after programming (learning) the initial starting point. Operation of the working radius: When the robot mows starting from a starting point to which you have assigned a radius, it first mows the entire circular area defined by this radius around the starting point. Once this area is completely mowed, it continues mowing in the rest of the main area. Steps to set the radius after defining the starting point: Access the robot's touchscreen menu in the “Starting Point Settings” section (section 11.15 of the manual) Select the starting point to which you want to assign a radius (starting point 1, 2, 3, or 4) Set the desired radius between 3 m and 30 m according to the area to be prioritized Confirm your setting Important point: By default, no radius is assigned to the registered starting points. The delimitation of the overall mowing area remains defined by the peripheral wire that you install around the lawn, placed about 28 centimeters from the edge of the area to be mowed. The wire can measure up to a maximum length of 500 meters. The radius assigned to the starting point allows the robot to manage hard-to-reach areas (small sector, isolated zone, etc.) by prioritizing them when starting from this specific point, rather than modifying the general delimitation of the peripheral wire.

Q: How to change the spark plug on the STIHL RM 2 RT lawn mower?

Changing the spark plug on the STIHL RM 2 RT lawn mower: Your lawn mower is equipped with a KOHLER HD675 engine (149 cm³) that uses a spark plug NGK DCPR6E (or the equivalent Champion RA6HC). The electrode gap should be set to 0.76 mm (0.030 inches) according to the manufacturer's specifications. Before you begin: Completely stop the engine and wait for it to cool down if the mower has just been used. Disconnect the rubber cable (terminal) from the spark plug to prevent any accidental restart during the operation. To remove the old spark plug: Use a spark plug wrench of about 20 mm or 21 mm (often included with the mower). Insert the wrench onto the spark plug and gently unscrew it by turning to the left. Remove it without forcing. Preparation and installation of the new spark plug: Before installing the new NGK DCPR6E spark plug, check that the gap between the center electrode and the side electrode is indeed 0.76 mm using a gap gauge or a coin (a 1 euro coin is about 0.77 mm). If the gap is incorrect, gently adjust it by bending the side electrode. Hand-thread the new spark plug into the threads to avoid cross-threading, then tighten it with the spark plug wrench without excessive force (a hand-tight plus a quarter turn with the tool is sufficient). Finalization: Firmly reconnect the cable (terminal) of the spark plug until it is well seated. Test the mower's starting to check that everything works correctly. If the mower does not start or runs irregularly, check that the terminal is properly connected and that the gap is correct. Practical tips: Change the spark plug every 100 hours of operation or once a year. If you are not comfortable with this operation or do not have the appropriate tool, contact an authorized STIHL dealer or a workshop specialized in lawn mowers.

Question 1

The mower starts but the blade does not engage

Accepted Answer

If your STIHL RMA 2 RPV starts (the motor runs) but the blade remains inactive, here are the points to check:

1. Check the correct engagement of the blade

According to the product manual, to activate the blade you must press and hold the safety button, then pull the mowing control lever fully towards the handlebar. If you do not pull the lever all the way, the blade will not engage.

2. Check the mowing control lever

The mowing control lever must be pulled fully towards the handlebar to engage the blade rotation at full speed. A partial or incomplete pull will prevent activation.

3. Check the battery

If the battery is low, the safety system may prevent the blade from engaging. Ensure that your STIHL AP battery is properly charged and securely inserted into the compartment.

4. Inspect the blade

According to the manual, the blade must have a minimum thickness of 2 mm and a minimum width of 45 mm. If the blade is worn, damaged, or dull, it may not engage properly. A dull blade should be sharpened by an authorized STIHL dealer.

5. Mower safety

The device has several automatic safety mechanisms. If any of the safety conditions are not met, the blade will not activate. Check that nothing obstructs the control levers and that all safety elements are in place.

If after these checks the blade remains inactive, contact an authorized STIHL service for diagnosis and repair.

Question 2

How to adjust the idle of the STIHL RM 650 VS engine?

Accepted Answer

The manual for the STIHL RM 650 VS does not include a section dedicated to adjusting the engine idle. This is not considered a standard maintenance adjustment that the user can perform themselves.

Why? The idle is a very specific parameter of this 4-stroke engine. An incorrect adjustment can affect starting, fuel consumption, and the overall reliability of the machine.

What you can check:

Oil level - refer to the section Before each use in your manual
Fresh fuel - use unleaded gasoline and check the recommended oil mixture
Clutch/brake - test several engagement/disengagement cycles to ensure the engine does not stall

If the engine stalls at idle or shows other anomalies, contact an authorized STIHL dealer who can diagnose and adjust the engine parameters if necessary.

Question 3

My STIHL RM 4 RTP lawn mower is difficult to start, what should I do?

Accepted Answer

If your STIHL RM 4 RTP lawn mower refuses to start or is difficult to start, here are the essential checks to perform in order:

Preliminary Checks

Engine Oil Level - Check that the oil level is sufficient before each start
Ignition Cable - Ensure that the ignition cable is properly connected to the spark plug terminal
Air Filter - A clogged filter can prevent starting. If the filter is dirty, contact a STIHL dealer for cleaning or replacement

Fuel Check

Empty Tank - Ensure that the tank contains fuel
Fuel Quality - Always use fresh unleaded brand gasoline with a minimum octane rating of 90. Do not use old gasoline or mixtures containing more than 10% ethanol

Spark Plug Check

If the spark plug is dirty, blackened, or damaged, clean or replace it

Correct Starting Procedure

Place the mower on a flat surface
With your left hand, push and hold the mowing control bar against the handle
Slowly pull the starter handle until you feel resistance
Pull quickly and let it return until the engine starts

If after these checks the engine still does not start, or if the air filter is really clogged, contact a STIHL dealer for a thorough diagnosis.

Question 4

Which batteries and chargers are compatible with the STIHL RMA 448 VC?

Accepted Answer

Authorized batteries:

The STIHL RMA 448 VC is powered exclusively by lithium-ion batteries from the STIHL AP series (36 V). Three models are compatible with this mower:

AP 100: maximum mowing speed 3.0 km/h, ideal for small areas
AP 200: maximum mowing speed 3.7 km/h, versatile use
AP 300: maximum mowing speed 4.5 km/h, for large areas

Recommended chargers:

Three STIHL charger models are compatible with all AP batteries to recharge your mower:

AL 101: compact and lightweight charger
AL 300: versatile mid-range charger
AL 500: high-end fast charger

Charging times: Charging times vary depending on battery capacity, charger model used, ambient temperature, and initial charge state. For exact durations based on your setup, refer to the charger manual or visit www.stihl.com/charging-times.

Important recommendations: Use only approved original STIHL batteries and chargers for this mower. Non-STIHL batteries can be dangerous (fire or explosion risks) and void the warranty. Store batteries at temperatures between -10 °C and +50 °C, and keep them clean and dry. For maintenance or repairs, contact a specialized STIHL dealer.

Question 5

How to set the working radius on the STIHL iMow RMI 422 mower robot after defining the starting point?

Accepted Answer

The STIHL iMow RMI 422 PC mower robot allows you to set a working radius around the starting points, between 3 meters and 30 meters. This radius is defined after programming (learning) the initial starting point.

Operation of the working radius: When the robot mows starting from a starting point to which you have assigned a radius, it first mows the entire circular area defined by this radius around the starting point. Once this area is completely mowed, it continues mowing in the rest of the main area.

Steps to set the radius after defining the starting point:

Access the robot's touchscreen menu in the “Starting Point Settings” section (section 11.15 of the manual)
Select the starting point to which you want to assign a radius (starting point 1, 2, 3, or 4)
Set the desired radius between 3 m and 30 m according to the area to be prioritized
Confirm your setting

Important point: By default, no radius is assigned to the registered starting points. The delimitation of the overall mowing area remains defined by the peripheral wire that you install around the lawn, placed about 28 centimeters from the edge of the area to be mowed. The wire can measure up to a maximum length of 500 meters.

The radius assigned to the starting point allows the robot to manage hard-to-reach areas (small sector, isolated zone, etc.) by prioritizing them when starting from this specific point, rather than modifying the general delimitation of the peripheral wire.

Question 6

How to change the spark plug on the STIHL RM 2 RT lawn mower?

Accepted Answer

Changing the spark plug on the STIHL RM 2 RT lawn mower:

Your lawn mower is equipped with a KOHLER HD675 engine (149 cm³) that uses a spark plug NGK DCPR6E (or the equivalent Champion RA6HC). The electrode gap should be set to 0.76 mm (0.030 inches) according to the manufacturer's specifications.

Before you begin: Completely stop the engine and wait for it to cool down if the mower has just been used. Disconnect the rubber cable (terminal) from the spark plug to prevent any accidental restart during the operation.

To remove the old spark plug: Use a spark plug wrench of about 20 mm or 21 mm (often included with the mower). Insert the wrench onto the spark plug and gently unscrew it by turning to the left. Remove it without forcing.

Preparation and installation of the new spark plug: Before installing the new NGK DCPR6E spark plug, check that the gap between the center electrode and the side electrode is indeed 0.76 mm using a gap gauge or a coin (a 1 euro coin is about 0.77 mm). If the gap is incorrect, gently adjust it by bending the side electrode. Hand-thread the new spark plug into the threads to avoid cross-threading, then tighten it with the spark plug wrench without excessive force (a hand-tight plus a quarter turn with the tool is sufficient).

Finalization: Firmly reconnect the cable (terminal) of the spark plug until it is well seated. Test the mower's starting to check that everything works correctly. If the mower does not start or runs irregularly, check that the terminal is properly connected and that the gap is correct.

Practical tips: Change the spark plug every 100 hours of operation or once a year. If you are not comfortable with this operation or do not have the appropriate tool, contact an authorized STIHL dealer or a workshop specialized in lawn mowers.

Question 7

How to adjust the cutting height of the blade on the STIHL RMA 339 C mower?

Accepted Answer

The STIHL RMA 339 C mower features a centralized adjustment lever that allows you to choose from 5 different cutting heights, ranging from 30 mm (Level 1, minimum height) to 70 mm (Level 5, maximum height).

Adjustment steps:

Step 1 - Release the lever: Press the height adjustment lever (1) to slightly pull it away from the mower until the lugs (2) completely release from the lever.
Step 2 - Adjust the height: Raise or lower the entire mower according to the desired cutting height. For a shorter cut, lower the mower. For a higher cut, raise it.
Step 3 - Lock the selection: Firmly press the height adjustment lever (1) towards the mower until the lugs (2) securely click into the lever.
Step 4 - Check the adjustment: The selected cutting height can be read directly at the front lug (3), which indicates the chosen level.

Height ranges: The RMA 339 C model offers 5 cutting levels ranging from 30 mm to 70 mm, allowing you to adapt the cutting height to your needs. Use the lower levels (30-45 mm) for well-maintained lawns, and the higher levels (55-70 mm) for taller or less regular grass.

Important recommendation: The minimum height (30 mm) should only be used on flat and well-maintained lawns to avoid damaging the mower. If the mower struggles to start in the grass, select a higher cutting height. Always ensure that the engine is off before changing the cutting height.

User manual STIHL Lawn mower : user manuals and guides in PDF

Models STIHL Lawn mower most viewed

Other categories STIHL

Recent questions about Lawn mower STIHL