Stihl HT 75 Manual

Safety Precautions and Working Techniques

Special safety precautions must be observed when working with the pole pruner because it operates at a very high chain speed, has very sharp cutters and a long reach.
It is important you read and understand the User Manual before commissioning and keep it in a safe place for future reference. Non-compliance with the User Manual may cause serious or even fatal injury.
Observe all applicable local safety regulations, e.g. by trade organizations, social insurance institutions, labor safety authorities etc.
If you have never used a power tool before: Have your dealer or other experienced user show you how to operate your machine – or attend a special course to learn how to operate it.
Minors are not allowed to work with the power tool – except adolescents above 16 years of age who are instructed under supervision.
Children, animals and bystanders must remain at a distance.
When not using the machine, it must be laid down in such a way that it does not endanger anyone. Ensure that the machine cannot be used without authorization.
The user is responsible for accidents or risks involving third parties or their property.
Do not lend or rent your power tool without the User Manual. Be sure that anyone using it understands the information contained in this manual.
The use of machines that emit noise may be limited to certain hours of the day as specified by national and/or regional or local regulations.
Anyone operating the machine must be well rested, in good physical health and in good mental condition.
If you have any condition that might be aggravated by strenuous work, check with your doctor before operating a machine.
If you have a pacemaker: The ignition system of your machine produces an electromagnetic field of very low intensity. This field may interfere with some pacemakers. STIHL recommends that persons with pacemakers consult their physician and the pacemaker manufacturer to reduce any health risk.
Anyone who has consumed alcohol or drugs or medicines affecting their ability to react must not operate a power tool.
Use your pole pruner for limbing only (removing or pruning branches). Saw wood and wooden objects only.
The machine must not be used for any other purposes – risk of accidents!
Only use guide bars, saw chains, chain sprockets and accessories that are explicitly approved for this power tool model by STIHL or are technically identical. If you have any questions in this respect, consult your dealer. Use only high quality parts and accessories. in order to avoid the risk of accidents and damage to the machine.
STIHL recommends the use of STIHL original tools, guide bars, saw chains, chain sprockets and accessories. They are specifically designed to match the product and meet your performance requirements.
Never attempt to modify your power tool in any way since this may increase the risk of personal injury. STIHL excludes all liability for personal injury and damage to property caused while using unauthorized attachments.
Do not use a high-pressure washer to clean the power tool. The solid jet of water may damage parts of the unit.

Clothing and equipment

Wear proper protective clothing and equipment.

Clothing must be sturdy but allow complete freedom of movement. Wear close-fitting clothes such as a boiler suit, not a loose jacket.
Do not wear clothing which could become trapped in wood, brush or moving parts of the machine. Do not wear a scarf, necktie or jewelry. Tie up and confine long hair above your shoulders.

Wear cut protection safety boots with non-slip soles and steel toe caps.

To reduce the risk of eye injuries, wear close-fitting safety glasses in accordance with European Standard EN 166. Make sure the safety glasses are a snug fit.
Wear "personal" sound protection, e.g. ear defenders.
Wear a safety hard hat where there is a danger of head injuries from falling objects.

Wear sturdy protective gloves made of a resistant material (e. g. leather).
STIHL can supply a comprehensive range of personal protective equipment.

Transporting the machine

Always stop the engine.
Always fit the chain scabbard – even when you carry the power tool for short distances.
Ensure that the power tool is always well balanced and hold it by the shaft for carrying. Do not touch hot parts of the machine, especially the surface of the muffler – Risk of burns!

By vehicle: When transporting in a vehicle, properly secure your machine to prevent turnover, damage and fuel spillage.

Refueling

Gasoline is highly flammable – keep away from fire or flame – do not spill any fuel – no smoking.
Always shut off the engine before refueling.
Do not fuel a hot engine – fuel may spill and cause a fire.
Open the fuel cap carefully to allow any pressure build-up in the tank to release slowly and avoid fuel spillage.
Only refuel the machine in a well ventilated place. If fuel has been spilled, immediately clean the machine – do not allow your clothes to be splashed with fuel. If that happens, change your clothes at once.
The power tools may be fitted as standard with different fuel caps.

After fueling, tighten down the screwtype fuel cap as securely as possible.

Place the clip lock fuel cap (bayonettype) in position, turn it as far as it will and fold the clip lock down.
This helps reduce the risk of unit vibrations causing an incorrectly tightened fuel cap to loosen or come off and spill quantities of fuel.
Check for leaks. Do not start the engine if there is a fuel leak – serious or fatal burns could result!

Before starting

Check that your power tool is properly assembled and in good condition – refer to appropriate chapters in the User Manual.

• Check the fuel system for leaks, especially the visible parts, e. g., fuel cap, hose connections, manual fuel pump (only in machines with a manual fuel pump). In case of leakage and damage, do not start the engine – risk of fire! Have the machine serviced by a dealer before using it
• Correctly mounted guide bar
• Correctly tensioned saw chain
• Slide control / stop switch must move easily to STOP or 0
• Throttle trigger lockout (if installed) and throttle trigger must move easily – the throttle trigger must return to the idle position automatically
• Check that the spark plug boot is secure – a loose boot may cause sparking that could ignite combustible fumes and cause a fire!
• Never attempt to modify the controls or safety devices
• Keep the handles dry and clean – free from oil and dirt – this is important for safe control of the machine
• Adjust the harness to suit your height and reach. Observe the chapter "Fitting the Harness"

To reduce the risk of personal injury, do not operate your power tool if it is damaged or not properly assembled!
If you use a harness: Practice setting down the machine quickly by removing the harness or by unhooking the machine as you would in an emergency. To avoid damage, do not throw the machine to the ground when practicing.

Starting the engine

Start the engine at least 3 meters from the fueling spot, outdoors only.
Place the power tool on level ground in an open area. Make sure you have good balance and secure footing. Hold the power tool securely. The chain must be clear of the ground and all other obstructions because it may begin to run when the engine starts.
Your power tool is designed to be operated by one person only. Do not allow other persons within a radius of 15 m of your own position – even when starting the power tool – Risk of injury!
Start the engine as described in the user manual.
The saw chain continues running for a short period when you release the throttle trigger – fly‐wheel effect!
Check engine idling speed: The saw chain must not move when the engine is idling – with the throttle trigger released.
Keep easily flammable materials (e.g. wood chips, bark, dry grass, fuel) away from the hot exhaust gas flow and the hot muffler surface – Risk of fire!

Holding and guiding the machine

Always hold the power tool firmly with both hands – right hand on the control handle, left hand on the drive tube – even if you are lefthanded. Wrap your thumbs firmly around the control handle and shaft.
Machines with telescopic shaft: Extend the telescopic shaft only as far as the working height.

While working

Make sure you always have good balance and secure footing.
In the event of impending danger or in an emergency, switch off the engine immediately - move the slide control/stop switch to STOP or 0.
This power tool is not insulated. Keep at least 15 m away from electric power lines – Danger of fatal electric shock!

Do not allow other persons within a radius of 15 m of your own position due to falling branches and ejected wood particles – Risk of injury!
This distance must also be maintained in relation to objects (vehicles, window panes) – risk of property damage!
Keep the bar nose at least 15 m away from electric power lines. Electric current may also arc over from high-voltage cables at greater distance. Have the power switched off before starting work in the immediate vicinity of power lines.
Switch off the engine before changing the saw chain – Risk of injury!
Ensure that the engine idling speed is correct. The saw chain must not move when the throttle trigger has been released.
It the saw chain continues moving, have the machine repaired by your specialist dealer. Check and correct the idle speed setting at regular intervals.
Never leave a running machine unattended.
Take special care in slippery, wet conditions, in snow and on slopes, uneven ground, etc. – Risk of slipping!
Watch out for obstacles: tree stumps, roots – risk of tripping or stumbling!

When working at heights:

• Always use a lift bucket
• Never use the machine while standing on a ladder or in a tree
• Never work on an insecure support
• Never use the machine with just one hand

Be particularly alert and cautious when wearing hearing protection because your ability to hear warnings (shouts, alarms, etc.) is restricted.
Take breaks when you start getting tired or feeling fatigue – risk of accidents!
Work calmly and carefully – in daylight conditions and only when visibility is good. Proceed with caution, do not put others in danger.

As soon as the engine is running, the power machine generates toxic exhaust gas. These gases may be odorless and invisible and may contain unburned hydrocarbons and benzene. Never run the engine indoors or in poorly ventilated locations, even if your model is equipped with a catalytic converter.
To reduce the risk of serious or fatal injury from breathing toxic fumes, ensure proper ventilation when working in trenches, hollows or other confined locations.
Stop work immediately if you start suffering from nausea, headaches, impaired vision (e.g. your field of vision gets smaller), impaired hearing, dizziness, or impaired concentration – these symptoms may possibly be the result of too-high exhaust gas concentration – Risk of accidents!
Operate your power tool so that it produces a minimum of noise and emissions – do not run the engine unnecessarily, accelerate the engine only when working.
To reduce the risk of fire, do not smoke while operating or standing near your power tool. Combustible fuel vapor may escape from the fuel system.
Dust (e.g. sawdust), fumes and smoke, generated while using the machine, may be hazardous to health. Wear a dust mask in case of dust formation.
If your power tool is subjected to unusually high loads for which it was not designed (e.g. heavy impact or a fall), always check that it is in good condition before continuing work – see also "Before Starting". Check in particular that the fuel system has no leaks and the safety equipment is fully operative. Never use a power tool that is no longer safe to operate. In case of doubt, contact a dealer.
If you use a harness, ensure that the exhaust gas flow is diverted away from your body – Risk of fire!

Limbing

Hold the power tool at an angle. Do not stand directly underneath the limb being cut. Do not exceed an angle of 60° from the horizontal. Watch for falling wood.

Keep the work area clear – remove interfering limbs and brush.
Before sawing branches, establish an escape route and remove all obstacles.

When performing the separating cut, position the bar against the branch near the hook. This will prevent the power tool from making jolting movements when you start the separating cut.

Start the cut with the saw chain at full throttle.
Always cut with a correctly sharpened, properly tensioned saw chain – the depth gauge setting must not be too large.
Do not operate your power tool in the starting throttle position – engine speed cannot be controlled in this position.
Perform cross-cut from the top downward to avoid the chain pinching in the cut.
If branches are thick or heavy, make a relief cut – see "Using the Pole Pruner".
Exercise extreme caution when sawing branches under tension – Risk of injury! Always make a relieving cut on the compression side first and then perform the bucking cut at the tension side.
Be careful when cutting splintered wood – Risk of injury from ejected pieces of wood!
If working on a slope, always stand uphill or to the side of the branch which is to be sawn. Watch out for rolling branches.
Note when reaching the end of a cut that the power tool is no longer supported by the guide bar in the cut. The user must bear the weight of the machine – risk of loss of control!
Always pull the power tool out of the cut with the saw chain running.
Use the power tool for limbing and pruning only, not for felling – Risk of accidents!
Keep the saw chain away from any foreign objects: Stones, nails, etc. may be ejected and damage the saw chain.
If a rotating saw chain hits a stone or another hard object, sparks may be generated which may ignite easily flammable materials under certain conditions. Also dried-out plants and brushwood are combustible, above all in hot and dry weather. If there is a risk of fire, do not use your pole pruner near easily flammable materials, dry plants or scrub. It is mandatory that you ask the responsible forestry office about the current fire hazard.
Before you leave the machine: Shut the engine off.

Vibrations

Prolonged use of the power tool may result in vibration-induced circulation problems in the hands (whitefinger disease).
No general recommendation can be given for the length of usage because it depends on several factors.
The period of usage is prolonged by:

• Hand protection (wearing warm gloves)
• Work breaks

The period of usage is shortened by:

• Any personal tendency to suffer from poor circulation (symptoms: frequently cold fingers, tingling sensations).
• Low outside temperatures.
• The force with which the handles are held (a tight grip restricts circulation).

Continual and regular users should monitor closely the condition of their hands and fingers. If any of the above symptoms appear (e.g. tingling sensation in fingers), seek medical advice.

Maintenance and Repairs

Service the machine regularly. Do not attempt any maintenance or repair work not described in the instruction manual. Have all other work performed by a servicing dealer.
STIHL recommends that you have servicing and repair work carried out exclusively by an authorized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
Only use high-quality replacement parts in order to avoid the risk of accidents and damage to the machine. If you have any questions in this respect, consult a servicing dealer.
STIHL recommends the use of genuine STIHL replacement parts. They are specifically designed to match your model and meet your performance requirements.
To reduce the risk of injury, always shut off the engine before carrying out any maintenance or repairs or cleaning the machine. – Exception: Carburetor and idle speed adjustments.
Do not turn the engine over on the starter with the spark plug boot or spark plug removed unless the slide control / stop switch is on STOP or 0 since there is otherwise a risk of fire from uncontained sparking.
To reduce the risk of fire, do not service or store your machine near open flames.
Check the fuel filler cap for leaks at regular intervals.
Use only a spark plug of the type approved by STIHL and make sure it is in good condition – see "Specifications".
Inspect the ignition lead (insulation in good condition, secure connection).
Check the condition of the muffler.
To reduce the risk of fire and damage to hearing, do not operate your machine if the muffler is damaged or missing.
Do not touch a hot muffler since burn injury will result.

Stopping the engine

• before checking chain tension.
• before retensioning the chain.
• before replacing the chain.
• before rectifying problems.

Observe sharpening instructions – keep the chain and guide bar in good condition at all times for safe and correct handling of the saw. The chain must be properly sharpened, tensioned and well lubricated.
Always change the chain, guide bar and sprocket in good time.
Store fuel and chain lubricant in properly labelled, safety-type canisters only. When handling gasoline, avoid direct contact with the skin and avoid inhaling fuel vapour – health risk.

Using the Unit

Preparation

• Wear suitable protective clothing, observe safety precautions
• Adjust the telescoping shaft to the required length
• Starting the engine
• Fitting the harness

Cutting sequence

To allow branches to free fall, always cut the lower branches first. Prune heavy branches (large diameter) in several controllable pieces.

Never stand directly underneath the branch you are cutting – be wary of falling branches. Note that a branch may spring back at you after it hits the ground – risk of injury.

Working technique

Hold the control handle with your right hand, and the shaft with your left hand. Your left arm should be extended to the most comfortable position.

The shaft should always be held at an angle of 60° or less.
The least tiring working position is a tool angle of 60°.
Any lesser angle may be used to suit the situation.

Cross-cut

To avoid pinching the bar in the cut, position the cutting attachment with the hook against the branch and then perform the cross-cut from the top downwards. The saw chain can be positioned precisely using the gauge bar.

Relieving cut

To avoid tearing the bark on thick branches, always start by performing a

• Relieving cut (1) on the underside of the branch. To do this, position the cutting attachment and guide it down to the bar nose in an arc.
• Perform the cross-cut (2) – position the bar with the hook against the branch and then perform the cross-cut

Flush-cutting thick branches

If branch diameter is more than 10 cm, first

• perform an undercut (3) and then cross-cut at a distance of about 20 cm (A) from the final cut. Then carry out the flush-cut (4), starting with a relieving cut and finishing with a crosscut

Cutting above obstacles

The machine's long reach makes it possible to prune branches that are overhanging obstacles, such as rivers or lakes. The tool angle in this case depends on the position of the branch.

Cutting from a lift bucket

The machine's long reach enables cutting to be performed next to the trunk without the risk of the lift bucket damaging other branches. The tool angle in this case depends on the position of the branch.

Cutting Attachment

A cutting attachment consists of the saw chain, guide bar and chain sprocket.
The cutting attachment that comes standard is designed to exactly match the pole pruner.

• The pitch (t) of the saw chain (1), chain sprocket and the nose sprocket of the Rollomatic guide bar must match.
• The drive link gauge (2) of the saw chain (1) must match the groove width of the guide bar (3).

If non-matching components are used, the cutting attachment may be damaged beyond repair after a short period of operation.

Chain Scabbard

The scope of supply includes a bar scabbard that matches the cutting attachment.
If guide bars of different lengths are mounted to the pole pruner, always use a chain scabbard of the correct length which covers the complete guide bar.
The length of the matching guide bars is marked on the side of the chain scabbard.

Mounting the Bar and Chain

Removing the chain sprocket cover

• Unscrew the nut and remove the cover
  
• Turn the screw (1) counterclockwise until the tensioner slide (2) butts against the left end of the housing slot, then back it off 5 full turns
  

Fitting the saw chain

Wear work gloves to protect your hands from the sharp cutters.

• Fit the saw chain – start at the bar nose
  
• Fit the guide bar over the screw (3) and engage peg of tensioner slide in the hole (4) – place the saw chain over the chain sprocket (5) at the same time
  
• Turn the tensioning screw (1) clockwise until there is very little chain sag on the underside of the bar – and the drive link tangs are engaged in the bar groove
• Refit the cover and screw on the nut fingertight
• Go to chapter on "Tensioning the Saw Chain"

Tensioning the Chain

Re-tensioning during cutting work:

• Shut off the engine
• Loosen nuts
• Raise the guide bar at the nose
• Use the screwdriver to turn the screw (1) to the right until the saw chain rests against the underside of the guide bar
• Raise the guide bar further and tighten the nuts securely
• Next step: Continue with "Checking Chain Tension"

A new saw chain has to be re-tensioned more often than one that has been in use for some time.

• Check chain tension frequently – see chapter on "Operating Instructions"

Checking Chain Tension

• Shut off the engine
• Wear work gloves to protect your hands
• The saw chain must fit snugly against the underside of the bar and it must still be possible to pull the chain along the guide bar by hand
• If necessary, re-tension the saw chain

A new saw chain has to be re-tensioned more often than one that has been in use for some time.

• Check chain tension frequently – see chapter on "Operating Instructions"

Adjusting the Throttle Cable

A properly adjusted throttle cable is the precondition for correct operation in the starting throttle, idle and full throttle positions.
Adjust the throttle cable only when the machine is completely and properly assembled.

• Use a suitable tool to push the slide to the end of the slot (see illustration).
  
• Press down the trigger lockout (1) and squeeze the throttle trigger (2) (full throttle position) – this sets the throttle cable correctly.
  

Fitting the Clip

Clip-On Carrying Ring

(only versions with telescoping shaft)
Position of carrying ring

Depending on the shaft length, the following positions are recommended:

• Telescoping shaft compressed, distance A = 15 cm (6 in)
• Telescoping shaft fully extended, distance B = 50 cm (20 in)

Fitting the clip-on carrying ring

• Squeeze the ends (arrows) together and push carrying ring onto the shaft.

Fuel

The engine requires a mixture of gasoline and engine oil.

Avoid direct skin contact with fuel and breathing in of gasoline fumes.

STIHL MotoMix

STIHL recommends using STIHL MotoMix. This pre-blended fuel is free of benzene and lead, is distinguished by a high octane rating, and always provides the proper mixing ratio.
STIHL MotoMix uses STIHL HP Ultra two-stroke engine oil for optimum engine life.
MotoMix is not available in all markets.

Mixing fuel

NOTICE
Unsuitable fuels or a mixing ratio that deviates from the specification can lead to severe engine damage. The engine, seals, fuel lines and fuel tank may be damaged if low-quality gasoline or engine oil is used.

Gasoline

Use only high-quality gasoline with an octane rating of at least 90 ROC – leaded or unleaded.
Gasoline with an alcohol component exceeding 10% can cause impaired engine performance in engines with manually adjustable carburetors and thus should not be used in these engines.
Engines with M-Tronic deliver full engine performance using gasoline with an alcohol component of up to 27% (E27).

Engine oil

If you mix the fuel yourself, use only STIHL twostroke engine oil or another high-performance engine oil classified as JASO FB, JASO FC, JASO FD, ISO-L-EGB, ISO-L-EGC or ISO-LEGD.
STIHL specifies STIHL HP Ultra two-stroke engine oil or an equivalent high-performance engine oil in order to maintain emission limits over the machine's service life.

Mixing ratio

with STIHL two-stroke engine oil 1:50; 1:50 = 1 part oil + 50 parts gasoline

Examples

• Pour oil into an approved safety fuel canister first, then add gasoline and mix thoroughly

Storing fuel mixture

Store in approved safety fuel canisters only in a dry, cool and secure place protected against light and sunlight.
Fuel mixture deteriorates with age – mix only as much as needed for a few weeks. Do not store fuel mixture for longer than 30 days. The fuel mixture can become unusable more quickly if exposed to light, sunlight or low or high temperatures.
STIHL MotoMix however can be stored for up to 5 years without any problems.

• Shake the canister containing the fuel mixture thoroughly before refueling

Pressure may have built up in the canister – open it carefully.

• The fuel tank and the canister in which fuel mixture is stored should be cleaned thoroughly from time to time

Residual fuel and the liquid used for cleaning must be disposed of in accordance with regula‐ tions and without harming the environment!

Fueling

Preparations

• Before fueling, clean the filler cap and the area around it to ensure that no dirt falls into the tank.
• Position the machine so that the filler cap is facing up.

Filling up with fuel

Take care not to spill fuel while fueling and do not overfill the tank. STIHL recommends you use the STIHL filler nozzle for fuel (special accessory).

After fueling, tighten down the filler cap as securely as possible by hand.

Changing the Fuel Pickup Body

Change the fuel pickup body every year:

• Open the filler cap and drain the fuel tank.
• Use a hook to pull the fuel pickup body out of the tank and take it off the hose.

NOTICE
Do not kink the fuel hose – do not use any sharp or pointed tools.

• Push the new pickup body into the hose.
• Place the pickup body in the tank.
• Fill up with fuel and close the filler cap.

Checking oil level

NOTICE
Check the level in the chain oil tank at frequent intervals and top it up as necessary.

Chain Lubricant

For automatic and reliable lubrication of the chain and guide bar – use only an environmentally compatible quality chain and bar lubricant.
Rapidly biodegradable STIHL BioPlus is recomfacing upwards mended.
NOTICE
Biological chain oil must be resistant to aging (e.g. STIHL BioPlus), since it will otherwise quickly turn to resin. This results in hard deposits that are difficult to remove, especially in the area of the chain drive and chain. It may even cause the oil pump to seize.
The service life of the chain and guide bar depends on the quality of the lubricant. It is therefore essential to use only a specially formulated chain lubricant.

Do not use waste oil. Renewed contact with waste oil can cause skin cancer. Moreover, waste oil is environmentally harmful.
NOTICE
Waste oil does not have the necessary lubricating properties and is unsuitable for chain lubrication.

Filling Chain Oil Tank

NOTICE
A full chain oil tank is sufficient for only half a tankful of fuel. Check the oil level regularly during cutting work. Never allow the oil tank to run dry

Preparations

• Thoroughly clean the fuel cap and the area around it to ensure that no dirt falls into the tank
• Position the machine so that the fuel cap is facing upwards

To open

• Open the bracket
  
• Twist fuel cap (ca. 1/4 turn)
  
  Markings on fuel cap and oil tank must align
  
• Remove the fuel cap
  

Filling up with chain oil

• Fill up with chain oil

Take care not to spill chain oil during refilling and do not overfill the tank.
STIHL recommends use of the STIHL filling system for chain oil (special accessory).

To close

Clip is in an upright position:

• Fit the fuel cap – marks on the fuel cap and oil tank must line up.
• Push the fuel cap down as far as it will go
• Hold the fuel cap down and twist it clockwise until it engages
  
  Then the markings on fuel cap and oil tank will align
  
• Close the bracket lock
  
  The fuel cap is locked
  

If the oil level in the tank does not go down, the reason may be a problem in the oil supply system: Check chain lubrication, clean the oilways, contact your dealer for assistance if necessary. STIHL recommends that maintenance and repair work be carried out only by authorised STIHL dealers.

If the fuel cap will not lock onto the oil tank

The base of the fuel cap is tilted in relation to the upper part.

• Remove the fuel cap from the oil tank and look at it from above
  
  left: Base of fuel cap is tilted – interior marking (1) is aligned with the exterior marking
  right: Bottom of the fuel cap in correct position – inner mark is under the grip. It does not align with the exterior marking
• Fit fuel cap and twist it counterclockwise until it engages in the seat of the filling port
  
• Continue to twist the fuel cap counterclockwise (approx. 1/4 turn) – this will twist the base of the cap into the correct position
• Twist the fuel cap clockwise and close it – see section "Closing"

Checking Chain Lubrication

The saw chain must always throw off a small amount of oil.

NOTICE
Never operate without chain lubrication. If the chain runs dry, the whole cutting attachment will be irretrievably damaged within a very short time. Always check chain lubrication and the oil level in the tank before starting work.
Every new chain has to be broken in for about 2 to 3 minutes.
After breaking in the chain, check chain tension and adjust if necessary – see "Checking Chain Tension".

Adjusting the Telescoping Shaft

Always shut off the engine and fit the chain scabbard!

• Loosen the clamp nut half a turn counterclockwise
  
• Adjust the shaft to the required length
• Tighten the nut clockwise

Fitting the Harness

The type and style of the harness depend on the market.

Shoulder Strap

• Put on the shoulder strap (1).
• Adjust the length of the strap.
• With the power tool attached, the carabiner (2) must be at about the same height as your right hip.

Backpack Carrying System

Backpack carrying system

• Put the backpack carrying system (1) on your back and adjust it as described in the instruction leaflet provided.
• Attach the carabiner (1) to the clip-on carrying ring (2) on the shaft.
• Attach the pole saw to the carrying strap when cutting.
• Adjust the hip belt (3), both shoulder straps (4) and the carrying strap (5).
  
• Squeeze the clip (carrying ring) together to move it up or down the shaft.
  

Starting/Stopping the Engine

Controls

1. Throttle trigger lockout
2. Throttle trigger
3. Slide control

Positions of slide control

4. STOP-0 – engine off – ignition is switched off
5. – normal run position – the engine is running or can start
6. START – ignition is switched on – the engine can start

Symbol on slide control

7. – stop symbol and arrow. To stop the engine, push the slide control in the direction of the arrow on the stop symbol () to STOP-0.

Starting

• Press down the trigger lockout lever and squeeze the throttle trigger
• and hold them in that position.
• Move the slide control to START and hold it there.
• Now release the throttle trigger, slide control and trigger lockout in that order. This is the starting throttle position.
• Set the choke lever (8) to
  if the engine is cold for warm start – also use this position if the engine has been running but is still cold.
  
• Press the manual fuel pump bulb (9) at least five times – even if the bulb is already filled with fuel.
  

Cranking

• Remove the chain scabbard. Check that the chain is not touching the ground or any other obstacles.
• Place the machine on the ground: It must rest securely on the engine support and the hook. If necessary, rest the hook on a raised support (e.g. a branch, mound or something similar).
  

Check that nobody is standing within the working range of the pruner.

• Make sure you have a safe and secure footing.
• Hold the unit with your left hand on the fan housing and press it down firmly – your thumb should be under the fan housing.

NOTICE
Do not stand or kneel on the shaft. This will bend the telescoping drive tube and may result in permanent damage.

When engine begins to fire

• Set the choke lever to .
• continue cranking.

As soon as the engine runs

• Blip the throttle trigger. The slide control moves to the normal run position – and the engine settles down to idle speed.

Make sure the carburetor is correctly adjusted. The cutting attachment must not run when the engine is idling.
Your machine is now ready for operation.

Stopping the Engine

• Push the slide control in the direction of the arrow on the stop symbol () to STOP-0.

At very low outside temperatures

As soon as the engine runs:

• Blip the throttle trigger to disengage the starting throttle position. The slide control moves to the normal run position – and the engine settles down to idle speed.
• Open the throttle slightly.
• Warm up the engine for a short period.

If the engine does not start

Choke Lever
If you did not move the choke lever to quickly enough after the engine began to fire, the combustion chamber is flooded.

• Set the choke lever to .
• Set the slide control, lockout lever and throttle trigger to the starting throttle position.
• Start the engine by pulling the starter rope briskly – 10 to 20 pulls may be necessary.

If the engine still does not start

• Move the slide control to STOP-0.
• Remove the spark plug – see "Spark Plug".
• Dry the spark plug.
• Open the throttle wide.
• Crank the engine several times with the starter to clear the combustion chamber.
• Refit the spark plug – see "Spark Plug".
• Move the slide control to START.
• Set the choke lever to – even if the engine is cold.
• Now start the engine.

Throttle cable adjustment

• Check adjustment of throttle cable – see chapter on "Adjusting the Throttle Cable".

Fuel tank run until completely dry

• After refueling, press the manual fuel pump bulb at least five times – even if the bulb is already filled with fuel.
• Set the choke knob to suit the engine temperature.
• Now start the engine.

Operating Instructions

During Break-In Period

A factory-new machine should not be run at high revs (full throttle off load) for the first three tank fillings. This avoids unnecessary high loads during the break-in period. As all moving parts have to bed in during the break-in period, the frictional resistances in the engine are greater during this period. The engine develops its maximum power after about 5 to 15 tank fillings.

During Operation

NOTICE
Do not make the mixture leaner to achieve an apparent increase in power – this could damage the engine – see "Adjusting the Carburetor".

Check chain tension frequently
A new chain has to be retensioned more often than one that has been in use for some time.

Chain cold
Tension is correct when the chain fits snugly against the underside of the bar and can still be pulled along the bar by hand. Retension if necessary – see "Tensioning the Saw Chain".

Chain at operating temperature
The chain stretches and begins to sag. The drive links must not come out of the bar groove – the chain may otherwise jump off the bar. Retension the chain – see "Tensioning the Saw Chain".
NOTICE
The chain contracts as it cools down. If it is not slackened off, it can damage the gear shaft and bearings.

After long period of full-throttle operation
Allow engine to run for a short while at idle speed so that engine heat can be dissipated by the flow of cooling air. This protects engine-mounted components (ignition, carburetor) from thermal overload.

After Finishing Work

• Slacken off the chain if you have retensioned it at operating temperature during cutting work.

NOTICE
Always slacken off the chain after finishing work. The chain contracts as it cools down. If it is not slackened off, it can damage the gear shaft and bearings.

Storing your saw for a short period
Fit the chain scabbard and allow engine to cool down. To avoid condensation, fill the fuel tank and keep the machine in a dry place, well away from sources of ignition, until you need it again.

Storing for a long period
See chapter on "Storing the Machine"

Taking Care of the Guide Bar

• Turn the bar over – every time you sharpen the chain and every time you replace the chain – this helps avoid one-sided wear, especially at the nose and underside of the bar
• Regularly clean the oil inlet hole (1), the oilway (2) and the bar groove (3)
• Measure the groove depth – with the scale on the filing gauge (special accessory) – in the area used most for cutting

  Chain type	Chain pitch	Minimum groove depth
  Picco	3/8" P	5.0 mm

  If groove depth is less than specified:

  • Replace the guide bar

The drive link tangs will otherwise scrape along the bottom of the groove – the cutters and tie straps will not ride on the bar rails.

Cleaning the Air Filter

Dirty air filters reduce engine power, increase fuel consumption and make starting more difficult.
Your power tool comes standard with either a clip-on or screw-mounted filter cover.

If there is a noticeable loss of engine power

• Set the choke lever to .

On the clip-on filter cover:

• Press in the tab (1) and swing the filter cover (2) away.

On the screw-mounted filter cover:

• Loosen the screw (3) and remove the filter cover (2).

On both versions:

• Clean away loose dirt from around the filter.
• Remove the foam and felt filter elements.
• Wash the foam element in a clean, non-flammable solution (e.g. warm soapy water) and then dry.
• Fit a new felt element – do not wash. As a temporary measure you can knock it out on the palm of your hand or blow it out with compressed air.

Replace any damaged parts.

• Fit the foam filter element (4) in the filter cover.
  
• Place the felt element (5) (lettering facing inwards) in the filter housing (6).
  
• Fit the filter cover.
• Clip the filter cover in position or tighten down the screw firmly.

Adjusting the Carburetor

The carburetor comes from the factory with a standard setting.
This setting provides an optimum fuel-air mixture under most operating conditions.
With this carburetor it is only possible to adjust the high speed screw within fine limits.

Standard Setting

• Shut off the engine.
• Check chain tension.
• Check the air filter and clean or replace as necessary.
• Check that the throttle cable is properly adjusted – readjust if necessary – see chapter on "Adjusting the Throttle Cable".
• Turn high speed screw (H) counterclockwise as far as stop (no more than 3/4 turn).
  
• Turn the low speed screw (L) carefully clockwise as far as stop, then turn it back 1 turn
• Start and warm up the engine.
• Adjust idle speed with the idle speed screw (LA) so that the chain does not run.

Fine Tuning

A slight correction of the setting of the high speed screw (H) may be necessary if engine power is not satisfactory when operating at high altitude or at sea level.

Rule of thumb:
Turn the high speed screw (H) about one quarter turn for every 1000 m (3300 ft) change in altitude.

Conditions for adjustment

• Carry out the standard setting.
• Warm up the engine for about 5 minutes.
• Open the throttle wide.

At high altitude

• Turn the high speed screw (H) clockwise (leaner), no further than stop, until there is no noticeable increase in engine speed.

At sea level

• Turn the high speed screw (H) counterclockwise (richer), no further than stop, until there is no noticeable increase in engine speed.

It is possible that maximum engine speed may be reached with the standard setting in each case.

Adjusting Idle Speed

It is usually necessary to change the setting of the idle speed screw (LA) after every correction to the low speed screw (L).

• Warm up the engine for about 5 minutes.

Engine stops while idling

• Turn the idle speed screw (LA) slowly clockwise until the engine runs smoothly – the chain must not rotate.

Chain rotates when engine is idling

• Turn the idle speed screw (LA) counterclockwise until the chain stops moving and then rotate the screw another 1/2 to 1 turn in the same direction.

If the chain continues moving when the engine is idling, have your machine checked and repaired by your servicing dealer.

Erratic idling behavior, engine stops even though setting of LA‑screw has been corrected, poor acceleration

Idle setting is too lean:

• Idle setting is too lean: Rotate the low speed screw (L) about 1/4 turn counterclockwise until the engine runs and accelerates smoothly.

Erratic idling behavior

Idle setting is too rich

• Rotate the low speed screw (L) about 1/4 turn clockwise until the engine runs and accelerates smoothly.

Spark Plug

• If the engine is down on power, difficult to start or runs poorly at idle speed, first check the spark plug.
• Fit a new spark plug after about 100 operating hours – or sooner if the electrodes are badly eroded. Install only suppressed spark plugs of the type approved by STIHL – see "Specifications".

Removing the Spark Plug

• Move the slide control to STOP-0.
• Pull off the spark plug boot (1).
  
• Unscrew the spark plug.

Checking the Spark Plug

• Clean dirty spark plug.
• Check electrode gap (A) and readjust if necessary – see "Specifications".
  
• Rectify the problems which have caused fouling of the spark plug.

Possible causes are:

• Too much oil in fuel mix.
• Dirty air filter.
• Unfavorable running conditions.

Arcing may occur if the adapter nut (1) is loose or missing. Working in an easily combustible or explosive atmosphere may cause a fire or an explosion. This can result result in serious injuries or damage to property.

• Use resistor type spark plugs with a properly tightened adapter nut.

Installing the Spark Plug

• Screw the spark plug (3) into the cylinder and fit the boot (2) (press it down firmly).
  

Storing the Machine

For periods of about 30 days or longer

• Drain and clean the fuel tank in a well-ventilated area.
• Dispose of fuel properly in accordance with local environmental requirements.
• If a manual fuel pump is fitted: Press the manual fuel pump at least 5 times.
• Start the engine and run it at idling speed until it stops.
• Remove saw chain and guide bar; clean and spray with protective oil
• Thoroughly clean the machine - pay special attention to the cylinder fins and air filter
• When using biological chain oil (e.g. STIHL BioPlus), fill the lubricant oil tank
• Store the machine in a dry and secure location Keep out of the reach of children and other unauthorized persons

Checking and Replacing the Chain Sprocket

• Remove chain sprocket cover, saw chain and guide bar

Replace the chain sprocket

• replace after using two saw chains or sooner
• if the wear marks (a) on the sprocket are deeper than approx. 0.5 mm (0.02 in) since this would reduce the service life of the saw chain. You can use a gauge (special accessory) to check the depth of the wear marks

Using two saw chains in alternation helps preserve the chain sprocket.
STIHL recommends the use of original STIHL chain sprockets.
The chain sprocket is driven via a friction clutch. Have the chain sprocket replaced by an authorized dealer.
STIHL recommends that maintenance and repair work be carried out only by authorized STIHL dealers.

Maintaining and Sharpening the Saw Chain

Cutting effortlessly with a correctly sharpened chain

A properly sharpened chain slices through wood effortlessly and requires very little feed pressure.
Do not work with a dull or damaged chain as it will increase the physical effort required, produce unsatisfactory results and a higher rate of wear.

• Clean the chain.
• Check the chain for cracks in the links and damaged rivets.
• Replace any damaged or worn parts of the chain and match the new parts to the shape and size of the original parts.

Carbide-tipped saw chains (Duro) are particularly wear resistant. STIHL recommends you have your chain resharpened by a STIHL servicing dealer.

It is absolutely essential to comply with the angles and dimensions specified below. If the saw chain is incorrectly sharpened – and in particular if the depth gauge is set too low – there is an increased risk of kickback, with resulting risk of injury.
The saw chain cannot be locked in place on the guide bar. Therefore, it is best to remove the chain from the bar and resharpen it on a workshop sharpening tool (FG 2, HOS, USG).

Chain pitch

The chain pitch (a) is marked on the depth gauge end of each cutter.

Select file diameter according to chain pitch – see table "Sharpening Tools".
You must observe certain angles when resharpening the chain cutter.

Filing and side plate angles

1. Filing angle
   STIHL saw chains are sharpened to a filing angle of 30°. Exceptions are ripping chains with a filing angle of 10°. Ripping chains have an X in their designations.
2. Side plate angle
   The correct side plate angle is obtained automatically if you use the prescribed file holder and file diameter.

   Cutter shapes	Angle (°)
   	A	B
   Micro = semi chisel cutter, e.g. 63 PM3, 26 RM3, 71 PM3	30	75
   Super = chisel cutter, e.g. 63 PS3, 26 RS, 36 RS3	30	60
   Ripping chain, e.g. 63 PMX, 36 RMX	10	75

   The angles must be the same on all cutters. If the angles are uneven: Chain will run roughly, not in a straight line, wear quickly and finally break.

File holder

• Use a file holder
  

A file holder must be used for manual resharpening (see table "Sharpening Tools"). The correct filing angles are marked on the file holder.

Use only special saw chain sharpening files.
Other files have the wrong shape and cut.

For checking angles

Use a STlHL filing gauge (special accessory, see table "Sharpening Tools"). This is a universal tool for checking the filing and side plate angles, depth gauge setting, cutter length and groove depth. It also cleans the guide bar groove and oil inlet holes.

File correctly

• Select sharpening tools according to chain pitch.
• If you use an FG 2, HOS or USG sharpener: Remove the chain from the bar and sharpen according to the instructions supplied with the tool.
• Clamp the bar in a vise if necessary.
• Sharpen the chain frequently, take away as little metal as possible – two or three strokes of the file are usually enough.
• Hold the file horizontally (at a right angle to the side of the guide bar) and file according to the angles marked on the file holder. Rest the file holder on the top plate and depth gauge.
  
• Always file from the inside to the outside of the cutter.
• The file only sharpens on the forward stroke – lift the file off the cutter on the backstroke.
• Avoid touching the tie straps and drive links with the file.
• Rotate the file at regular intervals while filing to avoid one-sided wear.
• Use a piece of hardwood to remove burrs from the cutting edge.
• Check angles with the filing gauge.

All cutters must be the same length.
If the cutters are not the same length, they will have different heights. This makes the chain run roughly and can cause it to break.

• Find the shortest cutter and then file all other cutters back to the same length. It is best to have this work done by a servicing dealer on an electric grinder.

Depth gauge setting

The depth gauge determines the height at which the cutter enters the wood and thus the thickness of the chip removed.

1. Specified distance or setting between depth gauge and cutting edge.

This setting may be increased by 0.2 mm (0.008") for cutting softwood in the mild weather season – no frost.

Lowering depth gauges

The depth gauge setting is reduced when the chain is sharpened.

• Use a filing gauge to check the setting every time you sharpen the chain.
• Place a filing gauge (1) that matches the chain pitch on the chain and press it against the cutter – if the depth gauge projects from the filing gauge, the depth gauge has to be lowered.
  

Saw chains with humped drive link (2) – upper part of humped drive link (2) (with service mark) is lowered along with the depth gauge.

The other parts of the humped drive link must not be filed since this may increase the kickback tendency of the power tool.

• File down the depth gauge until it is level with the filing gauge.
  
• File the top of the depth gauge parallel to the stamped service marking (see arrow) – but do not lower the highest point of the depth gauge in this process.
  

The kickback tendency of the machine is increased if the depth gauges are too low.

• Place the filing gauge on the chain – the highest point of the depth gauge must be level with the filing gauge.
  
• After sharpening, clean the chain thoroughly, remove filings or grinding dust – lubricate the chain thoroughly.
• Before a long out-of-service period, clean the chain and store it in a well-oiled condition.

Maintenance and Care

Minimize Wear and Avoid Damage

Observing the instructions in this manual helps reduce the risk of unnecessary wear and damage to the power tool.
The power tool must be operated, maintained and stored with the due care and attention described in this owner's manual.
The user is responsible for all damage caused by non-observance of the safety precautions, operating and maintenance instructions in this manual. This includes in particular:

• Alterations or modifications to the product not approved by STIHL.
• Using tools or accessories which are neither approved or suitable for the product or are of a poor quality.
• Using the product for purposes for which it was not designed.
• Using the product for sports or competitive events.
• Consequential damage caused by continuing to use the product with defective components.

Maintenance Work

All the operations described in the "Maintenance Chart" must be performed on a regular basis. If these maintenance operations cannot be performed by the owner, they should be performed by a servicing dealer.
STIHL recommends that you have servicing and repair work carried out exclusively by an authorized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
If these maintenance operations are not carried out as specified, the user assumes responsibility for any damage that may occur. Among other parts, this includes:

• Damage to the engine due to neglect or deficient maintenance (e.g. air and fuel filters), incorrect carburetor adjustment or inadequate cleaning of cooling air inlets (intake ports, cylinder fins).
• Corrosion and other consequential damage resulting from improper storage.
• Damage to the machine resulting from the use of poor quality replacement parts.

Parts Subject to Wear and Tear

Some parts of the power tool are subject to normal wear and tear even during regular operation in accordance with instructions and, depending on the type and duration of use, have to be replaced in good time. Among other parts, this includes:

• Saw chain, guide bar
• Drive components (clutch, clutch drum, chain sprocket)
• Filters (air, oil, fuel)
• Starter mechanism
• Spark plug
• Components of antivibration system

Main Parts

1. Telescopic shaft
2. Clip
3. Slide control
4. Throttle trigger lockout
5. Throttle trigger
6. Spark plug boot
7. Air filter cover
8. Machine support
9. Oilomatic saw chain
10. Guide bar
11. Oil tank
12. Oil tank cap
13. Telescopic shaft
14. Clamp nut
15. Chain sprocket cover
16. Hook
17. Chain scabbard
18. Chain sprocket
19. Chain tensioner
20. Gauge bar
21. Fuel tank
22. Fuel cap
23. Starter grip
24. Manual fuel pump
25. Choke lever
26. Carburetor adjusting screws
27. Muffler (for some international markets: with spark arresting screen)

# Serial number

Specifications

Engine
STIHL single-cylinder two-stroke engine

Ignition system
Electronic magneto ignition

Fuel system
All-position diaphragm carburetor with integral fuel pump
Fuel tank capacity: 440 cm³ (0.44 l)

Chain lubrication
Fully automatic, speed-controlled oil pump with rotary piston
Oil tank capacity: 220 cm³ (0.22 l)

Weight
Dry, without cutting attachment
HT 75: 7.3 kg

Cutting attachment
The actual cutting length may be less than the specified cutting length.

• Rollomatic E Mini/Rollo Light 01 guide bar

  Blade length:	25, 30, 35 cm
  Pitch:	3/8" P (9.32 mm)
  Groove width:	1.1 mm

• Saw chain 3/8" P
  Picco Micro Mini 3 (61 PMM3) Type 3610

  Pitch:	3/8" P (9.32 mm)
  Drive link gauge:	1.1 mm

• Chain sprocket
  6-tooth for 3/8" P

Sound and Vibration Values
Noise and vibration data measurements include idling and rated maximum speed with the same duration of exposure.
For further details on compliance with Vibration Directive 2002/44/EC, see www.stihl.com/vib

• Sound pressure level L_peq in accordance with ISO 22868
  HT 75: 92 dB(A)
• Sound power level Lw acc. to ISO 22868
  HT 75: 110 dB(A)
• Vibration level a_hv,eq acc. to ISO 22867

  Shaft compressed
  Shaft:	4.6 m/s2
  Control handle:	5.4 m/s2
  Shaft extended
  Shaft:	6.0 m/s2
  Control handle:	5.1 m/s2

  The K‑factor in accordance with Directive 2006/42/EC is 2.0 dB(A) for the sound pressure level and sound power level; the K‑factor in accordance with Directive 2006/42/EC is 2.0 m/s² for the vibration level.

Maintenance and Repairs

Users of this machine may only carry out the maintenance and service work described in this user manual. All other repairs must be carried out by a servicing dealer.
STIHL recommends that you have servicing and repair work carried out exclusively by an authorized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
When repairing the machine, only use replacement parts which have been approved by STIHL for this power tool or are technically identical. Only use high-quality replacement parts in order to avoid the risk of accidents and damage to the machine.
STIHL recommends the use of original STIHL replacement parts.
Original STIHL parts can be identified by the STIHL part number, the logo and the STIHL parts symbol (the symbol may appear alone on small parts).