JF FCT 1460, Directions For Use Manual, Page: 25 / 114

2. CONNECTION TO TRACTOR
PIGB-206X-02 FCT1460 0614
- 25 -
BYPASS VALVE
Fig. 2-1
We distinguish between two types of tractor hydraulic systems: “open centre
hydraulic” (also called “fixed pump”) and “closed centre hydraulic” (also called
“variable pump”).
If the tractor is of the
“open centre”
type, the bypass valve must be open in order to
allow passage of oil back to the tractor and should only be activated when a function
on the machine is activated. If the valve is not open, this can be changed at the
thumbscrew.
If the tractor is of the
“closed centre”
type, the bypass valve must be closed in
order to allow the tractor to close the oil flow automatically when no functions are
active. If the valve is not closed, this can be changed at the thumbscrew.
The bypass valve is placed at the left on the valve block.
None of the hydraulic functions use more than about 15 litres of oil per minute.
Therefore the oil flow from the tractor should be set to 15 litres of oil per minute, if
possible. The bypass valve is preset to maximum 40 l/min. If this limit is exceeded,
there will be a loss of pressure which may heat the oil and the valves.
P
R
1
1
-1
7
4
3
Closed centre
Open centre
Fig. 2-1