Bush Hog CBH70, CBH80, CBH60 manual Troubleshooting

Troubleshooting (Continued)
	Problem	Cause	Correction
	Unable to push valve	Bent spool	Replace with new spool section.
	spool in
		Foreign particles	Clean system and valve.
		Misalignment of control handle	Check linkage for binding condition.
		linkage
	Spring centered spools	Paint on valve spool; sticking	Clean valve spool. Binding is usually
	do not return to neutral	valve spool or scored valve	caused from an over tightened plug,
		spool	mounting bolt, fitting in valve body or
			tie rod bolt. If a plug or fitting in the
			valve body is leaking, do not overtighten
			in an effort to stop leak. This will distort
			body casting and cause spools to bind.
			Instead, the plug and fitting should be
			removed from valve body and be
			reconnected, using a new O-ring. Do
			not apply excessive pressure on
			mounting bolts. The rods for CBH70,
			CBH80 should be torqued to 14 ft/lbs for
			5/16” nuts and 33 ft/lbs for 3/8”nuts.
			Never force spool.
		Oil leakage past spool seal into	Remove cap. If it contains oil replace spool
		spool cap	seal O-rings. Check O-ring retainer to be
			sure it is flat. If it has been “belled” check
			for restriction from outlet to reservoir of
			valve which would cause excessive back
			pressure. If supply and return lines are
			reversed, pressure on low pressure / return
			side of valve will cause problem.
			Make sure hoses are connected correctly
			at bulkhead connection on backhoe.
		Broken return springs	Replace springs.
		Bent spool	Replace with new spool section.
		Foreign particles	Clean system and valve.
		Misalignment of control handle	Check linkage for binding condition.
		linkage

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