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O p e r a t i o n a n d M a i n t e n a n c e
154
Sliding Rotator Wreckers – Operation and Maintenance
Models: CSR50 - CSR65 - CSR85
REV. 0
SEPTEMBER 19, 2022
5.2
Checking the boom cylinder
You need to check the boom cylinder if the boom:
l
Retracts by itself when lifting a (heavy) load with the winches.
l
Extends by itself when lifting a load on the underlift. The underlift tilts down when the
boom extends.
The problem might be due to a leaking piston, damaged seal or broken cartridge in the lock
valve block.
The following troubleshooting procedure isolates a boom cylinder and checks it for leaks. If you
push oil onto one side of a cylinder and the other side is vented, no oil should leak unless there
is a broken piston, damaged seal or broken cartridge.
NOTE: You will need a load (e.g. another vehicle) for this procedure.
1. Lower the underlift completely.
2. Choose a lifting point on the vehicle to be towed. It must be both strong enough and have
enough clearance for the underlift to move.
Using a poor lifting point may damage the towed vehicle and wrecker or even
cause a serious accident.
3. Use the safety chains and tensioner to hold the vehicle in place on the underlift’s T-bar.
4. Fully retract the boom and keep it retracted using a winch cable hooked to the D-ring on
the wrecker.
5. Stop the hydraulic system.
6. Disconnect the two hoses coming from the bottom of the square bushings at the end of
the boom cylinder rods.
7. Put a cap on the ends of each hose. This prevents the oil from leaving the cylinder
through the hoses.