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© 2011 ICS- Blount Inc Specifications and pricing are subject to change without notice. P/N 525747 REV12Sep2012
680GC SERVICE MANUAL
26.3
The fuel tank breather stabilizes the pressure in
the fuel tank preventing both excessive pressure,
which could flood the engine, and negative
pressure, which could starve the engine of fuel.
26.4
Fuel tank breather is located inside the air filter
compartment.
26.5
Testing the fuel tank breather.
A. Attached the pressure gauge and bulb to
the main fuel pick-up tube at the carburetor.
Pressurize the tube to 4.5 psi (0.3 bar).
B. The pressure should reduce to nearly 0 psi
(0 bar) over about 3 seconds.
26.6
If the pressure does not reduce to 0 psi,
disassemble or replace the breather.
A. Clean the parts with solvent or fuel.
B. Assemble in reverse order.
C. Make sure that the spring taper is oriented in
the correct direction. Narrow end towards the end
of the cap.
26. FUEL SYSTEM LEAKS
