Bush Hog CBH80, CBH60 manual Closed Center System CBH 60 & CBH70

1.OPEN-CENTER SYSTEM WITH LOADER VALVE OR OTHER ACCESSORY VALVE CONNECTED TO THE TRACTOR HYDRAULIC SYSTEM

When a loader valve	or other accessory valve must
be connected to the tractor hydraulic system in addi-
tion to th e backhoe control valve, a		Power Beyond
Kit is required. This kit converts the backhoe valve so
that pr essur ized hyd raulic oil ca n be di recte d to
another open-center	valve for a loa	der or other
accessory. This allow s th e backhoe valv e and the
other valve to be connec ted to the tra ctor hydraulic
system simultaneously, without the inconvenience of
using a flow diverting valve.

Since the Pow er Beyond Kit is used w ith open-cen- ter tra ctor h ydraulic systems, o il co nstantly fl ows from the pump, through the backhoe valve and then to the reservoi r. Se e fu rthe r in this manual for instructions on proper assembly.

2.CLOSED CENTER SYSTEM: (CBH 60 & CBH70)

Because a closed -center system requires no flow of oil t hrough the back hoe c ontrol valve when the levers are in a neutral position, the CBH 60 & CBH 70 backhoe must not be connected to a closed-cen- ter tractor hydraulic system.

IMPORTANT: Do n ot connect a CBH 60 & CBH 70 backhoe control valve to a closed- center trac- tor hydraulic system, or seri ous damage to backhoe valve or tractor hydrau lic sy stem may result.

3.OPEN-CENTER S YSTEM WITH RE TURN OI L NOT REQUIRED FOR LUBRICATION-Figure 19

The pressure hose	(A) s hould be connec ted from
the pre ssure po rt on the backhoe		to the pressure
Figure 19
Backhoe Control		To Tractor
Valve
CBH 70 & 80	B	Reservoir
Shown		Coupler
		A
Pressure		To Pressure Port
		of Oil Supply
	Hoses Supplied
	by Customer

port of the tractor remote co uplers or directly to the tractor v alve. The return hos e (B ) should be con - nected from the tank (return) port o n the backhoe to a port on the reservoir, as shown in Figure 19.

IMPORTANT: Never connect the return hose to a tractor remote c oupler w hich can be pre ssur- ized. A ccidental pressurization can cause se ri- ous damage to backhoe valve.

4.OPEN-CENTER SYSTEM W ITH RETURN OIL REQUIRED FOR LUBRICATION - Figure 20

On some tractors, the return oi l cannot be rout ed directly to the reservoir because it is required for the lubrication of other functions. Check this characteris- tic with your dealer. The pressure hose (A) must be connected from the pressure port on the backhoe to the pressure port of the tract or’s remote couplers or directly to t he tracto r valve. The r eturn hose (B) must be connected from the tank (return) port on the backhoe to a surge relief valve a s shown in Figu re 20.

NOTE: The s urge relief val ve is not supplied with the bac khoe or mou nting kit an d mus t be order ed separately to complete this type hydraulic hook-up.

Complete the hydrauli c hook-up by con necting th e
surge relief valve to the return port of tractor remote
couplers or directly to the tractor valve, and by con -
necting a ho se f rom TANK port of	the surge r elief
valve to the tractor reservoir as shown in Figure 20.
The surge relief valve is used to protect the backhoe
valve from da mage caus ed by accidental pressur-
ization or high back pressure buil	d-up. If thi s ha p-
pens, oil w ill be vented from the TANK port of the

surge relief valve to the tractor reservoir to prevent loss of vented oil.

Figure 20	To Tractor		To Return Port
Backhoe Control	Resevoir
			of Oil Supply
Valve
CBH 70 & 80			B
Shown
			A Couplers
		Hoses Supplied
Pressure		by Customer
			To Pressure Port
			of Oil Supply
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