Checking Overflow Valve; Changing Fuel Feed Pump Valves - Valtra 6000 Workshop Manual

22. Fuel system
D. Checking overflow valve
If the fuel feed pressure deviates from the prescribed value,
check the opening pressure of the overflow valve.
1. Connect a pressure gauge to the banjo union in the same
way as in previous instruction C.
2. Pump with the hand pump until the overflow valve opens.
Compare the reading on the gauge at the moment the valve
opens with the prescribed value (0,6 ---1,0 bar).
3. If the recorded opening pressure deviates from the pre-
scribed value, the overflow valve should be changed.
N.B. If the recorded pressure is considerably lower than the
prescribed value, there may be a fault in the hand pump or
the fuel feed pump valves.
1. 9. 1992
E. Changing fuel feed pump valves
1. Clean the feed pump. Disconnect fuel pipes to the feed
pump. Remove the feed pump.
2. Secure the pump in a vice provided with soft jaws. Loosen
the tappet body from the pump and remove the piston, seal
rings, suction valve and the spring.
3. Detach from the pump body the outlet side threaded con-
nector, in which is placed the pressure valve.
4. Rinse the valves with clean fuel and check the function and
possible wear.
5. Change the valve if needed and assemble the pump using
new o---rings and gasket
108
Model Code
6000-- 8750 222
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