Toro Sand Pro 3040 Service Manual page 64

Evaporative Control System (continued)
Engine: Service and Repairs
vacuum unseats the check valve which then allows vapors from the canister to
flow to the engine purge port. These vapors are then consumed by the engine.
When the engine is not running, evaporative vapors remain in the fuel tank and
carbon canister.
Note: If there is restriction in the carbon canister, the rollover valve or the vent
hose, the fuel tank may distort due to venting issues. If the fuel tank returns to
it's normal shape when the fuel cap is removed, restriction in the evaporative
control system is likely.
Refer to Figure 13 for this procedure.
1. Inspect the carbon canister and attached hoses for damage or leaks. A
damaged or leaking canister should be replaced.
2. Ensure the fresh air filter behind the carbon canister is not blocked.
3. Ensure all evaporative control system hoses are not kinked or pinched and
are secured at each end with hose clamps.
4. Test the operation of the check valve. The valve should open (allow flow
through the valve) when approximately 100 mm Aq (0.29 inch Hg) vacuum
is applied to port A. There should be no flow through the valve when the
same amount of vacuum is applied to port B.
5. Repair or replace evaporative system components as necessary. Ensure the
arrow on the check valve is pointed toward the engine purge port during
installation.
Page 4–14 Sand Pro ® 3040 and 5040
20251SL Rev A