Bush Hog CBH80 - Manual (Page 22)

Troubleshooting (Continued)
Problem Cause Correction
Loss of power in any one Scored piston rods and worn Replace or rebuild the cylinder; replace
cylinder, including lift guides in cylinder damaged parts.
and crowd (cont.)
Bent piston rod in cylinder Replace or rebuild the cylinder; replace
damaged parts.
Worn or damaged rod seals on Repack cylinder. Rebuild cylinder,
cylinder; external leaks replacing damaged parts as necessary.
Spool not moved to full stroke Check spool travel - should be .16”
either way, or a total of .32” for CBH60.
Spool travel should be .28” either way,
or a total of .56” for CBH70 CBH80.
Overload relief valve in the control Clean relief carefully but do not disturb
valve stuck open or malfunctioning its pressure setting as it cannot be field
calibrated, or replace cartridge.
Worn control valve Replace the control valve.
Loss of power in swing Loose oil line connections, Tighten all hose connections and
cylinders, but other leaks in line or broken lines replace any damaged O-rings at
cylinders functioning leaking O-ring fittings. Check and
properly. replace any damaged hoses and lines.
Restrictions in oil lines Check and replace any damaged hoses
and lines. Check for pinched hoses.
Oil is bypassing cylinder piston, Replace or rebuild the cylinder; replace
scored piston, worn piston damaged parts.
packing, or defective piston
assembly
Scored piston rods and worn Replace or rebuild the cylinder; replace
guides in cylinder damaged parts.
Bent piston rod in cylinder Replace or rebuild the cylinder; replace
damaged parts.
Worn or damaged rod seals on Repack cylinder. Rebuild cylinder,
cylinder; external leaks replacing damaged parts as necessary.
Spool not moved to full stroke Check spool travel - should be .16”
either way, or a total of .32” for CBH60.
Spool travel should be .28” either way,
or a total of .56” for CBH70 CBH80.
Relief valve setting in backhoe Relief pressure will have to be checked
control valve too low or and corrections made. Backhoe
defective system pressure is 2000 PSI (CBH60),
2250 PSI (CBH70), 2550 PSI (CBH80),
Relief valve may need cleaning and or
overhauling or entire cartridge must be
replaced.
Worn control valve Replace the control valve.
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