Stihl Ht 75 Owners Manual

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HT 70, HT 75 For automatic and reliable 
lubrication of the chain and guide 
bar: Use only a quality, 
environmentally compatible 
chain and bar lubricant. STIHL 
chain lubricant with non-fling 
additive or the rapidly 
biodegradable STIHL BioPlus is 
recommended.
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....

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The bayonet-type oil tank filler cap with 
its hinged clip can be opened and closed 
without tools.
:To open the tank, swing the clip (1) 
to the vertical position.
:Turn the filler cap counterclockwise 
as far as stop and remove.
:Fill up with chain oil.
:To close the oil tank, place the filler 
cap in position with the clip vertical, 
making sure the recesses (2) are in 
alignment.
:Turn the filler cap clockwise as far 
as stop.
:Fold the clip down so that it is flush 
with the...

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HT 70, HT 75Shoulder strap*:Put on the shoulder strap (1).
:Adjust length of strap so that the 
spring hook (2), with the unit 
attached, is at about the same 
height as your right hip. 
* see “Guide to Using this Manual“
Full harness*:Put on the full harness (1) and 
sling (2) as shown on the instruction 
sheet supplied.
:Adjust the harness and thigh belt (3) 
as required.
:Rest the powerhead in the sling 
during cutting work.
*see “Guide to Using this Manual”
Fitting the Harness
21
390BA040...

23 HT 70, HT 75english
ControlsThrottle trigger interlock (1), throttle 
trigger (2) and slide control (3) with the 
positions:
START (4)
The normal run position # (5)
and
$ – STOP (6) for stopping the engine..
Starting:Hold down the trigger interlock and 
squeeze the throttle trigger.
:Keep both levers in that position.
:Move the slide control to START 
position and hold it there.
:Now release the throttle trigger, 
slide control and trigger interlock in 
that order. This is the 
starting-throttle...

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HT 70, HT 75 :Place the unit on the ground: 
It must rest securely on the engine 
support and the hook.
:Remove the chain guard.
Check that chain is not touching any 
object or the ground. 
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 firm footing: 
Press the unit firmly against the 
ground with your left hand on the fan 
housing. Your thumb should be...

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Alternative method:
:Remove the chain guard.
Position the shaft on a branch so 
that it is held by the hook.
:Hold the unit firmly with your left 
hand around the fan housing – your 
thumb under the fan housing.:Pull the starter grip slowly with your 
right hand until you feel it engage –
and then give it a brisk strong pull. 
Do not pull out starter rope to full 
length – it might break.
:Do not let the starter grip snap back 
– guide it slowly into the housing so 
that the...

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HT 70, HT 75At very low temperatures
As soon as engine runs:
:Blip the throttle trigger – the slide 
control moves to the run position #, 
and the engine returns to idling 
speed.
:Open throttle slightly – warm up 
engine for short period.
If the engine does not startIf you did not move the choke to e 
quickly enough after the engine began to 
fire, the combustion chamber is flooded.
:Set choke lever to  e.
:Set slide control, interlock lever and 
throttle trigger to starting throttle...

27 HT 70, HT 75english
During break-in periodA 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.
Do not make the mixture leaner to 
achieve an apparent increase in...

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HT 70, HT 75 :Turn the bar over – 
every time you sharpen the chain – 
and every time you replace the 
chain – this avoids one-sided wear, 
especiallly at nose and underside of 
the bar.
Regularly clean
1 =oil inlet hole
2 =oil passage
3 =bar groove:Measure groove depth –
with scale on filing gauge – see 
“Special Accessories“ – in area 
used most for cutting on Rollomatic 
bars.
If groove depth is less than specified:
:Replace the guide bar.
The drive link tangs will otherwise 
scrape along...

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:Wash the foam element in a clean, 
non-flammable cleaning solution 
(e.g. warm soapy water) and then 
dry.
:Fit new felt element. 
As a temporary measure you can 
knock it out on the palm of your 
hand or blow it out with compressed 
air. Do not wash.
Replace damaged parts!
:Install the foam element (3) in the 
filter cover (2).
:Place felt element (4) (lettering 
facing inward) in filter housing (5).
:Fit filter cover so that it snaps into 
position.Exhaust emissions are...