Air Fi Lter; Tank Venting - Husqvarna 122C Workshop Manual

3
In addition to the fuel tank and carburettor, the fuel system consists of the air fi lter, fuel fi lter and tank ven-
ting.
All these components interact so that the engine receives the optimal mixture of fuel and air to make it as
effi cient as possible. Very small deviations in the carburettor setting or a blocked air fi lter have a large effect
on the running and effi ciency of the engine.
The carburettor can come from several different manufacturers on our models, but the function and repair
methods are essentially the same.
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Fuel system
Air fi lter
Dismantle the air fi lter and clean it in warm
soapy water.
Replace the fi lter if it is damaged.
505 69 85-70
Impregnate the fi lter with air fi lter oil.
531 00 60-76

Tank venting

Check that the tank venting works cor-
rectly.
531 03 06-23
Air fi lter
Remove the cover over the carburettor
and lift off the air fi lter.
The fi lter is manufactured of foamed plas-
tic and should be cleaned in warm soapy
water.
A damaged fi lter should be replaced with
a new fi lter.
!
WARNING!
Do not clean not the fi lter
with petrol. Hazardous!
NOTE!
Do not blow the fi lter clean with
compressed air. It can be damaged.
Ensure that the fi lter is dry before
refi tting it.
TIP!
Use Husqvarna's cleaning agent Active
Cleaning no. 505 69 85-70.
Impregnate the fi lter with air fi lter oil.
TIP!
Place the fi lter in a plastic bag and pour
about a tablespoon of air fi lter oil no.
531 00 60-76 into the bag.
Massage the oil into the air fi lter.
Tank venting
The tank venting valve is fi tted in a sepa-
rate hose from the fuel tank and it is im-
portant that the valve functions for engine
operation, especially at low speeds, i.e. to
allow air into the tank but prevent fuel from
being forced out.
1. Empty the fuel from the tank and re-
move the fuel hose from the carburettor.
2. Connect the fuel hose to pressure tester
no. 531 03 06-23.
3. Check that there is no vacuum build up
in the tank.
4. Pump up the tank to generate excess
pressure (about 20 kPa). The pressure
should drop to atmospheric pressure
within 30 seconds.