Husqvarna 545 Mark II Workshop Manual page 53

7. Attach the fuel filter to a new fuel hose.
8. Close the fuel tank cap.
9. Assemble the fuel tank in the opposite sequence to
how it was disassembled.
8.15.5 To replace the air purge bulb
1. Disassemble the cylinder cover and the air filter.
2. Loosen the suction hose (A) and the return hose (B)
from the air purge bulb.
3. Push the snap locks to remove the air purge bulb
from the air filter holder.
A
B
4. Replace the air purge bulb.
5. Assemble the air purge bulb in the opposite
sequence to how it was disassembled.
8.15.6 Air pressure in the fuel tank
The two-way tank valve has a controlled opening
pressure in the two directions. The controlled opening
prevents positive pressure or vacuum in the fuel tank,
and fuel leakage. Positive pressure, vacuum and fuel
leakage decreases engine performance.
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8.15.6.1 To do a pressure test of the fuel tank
1. Open the fuel tank cap and drain the fuel from the
tank. Pull out and remove the fuel hose as the
illustration shows.
2. Connect the pump to the tank valve (A).
3. Do a pressure test of the outwards pressure.
a) Use the pump in vacuum mode.
b) Read the indicator, it must be between 0.10-0.45
bar.
4. Do a pressure test of the inwards pressure.
a) Use the pump in pressure mode.
b) Read the indicator, it must stop at max. 0.07 bar.
5. Close the fuel tank cap.
8.15.7 To assemble the tank unit
• Assemble the tank unit in the opposite sequence to
how it was disassembled.
A
Repair instructions - 53