General; Introduction; How The Winch Operates - Allied Systems W8L Operating Manual

Introduction

This Operating Manual contains basic information
necessary for the operation and maintenance of the W8L
winch.

How the Winch Operates

A winch is normally installed on a skidder or dozer:
• to increase the pulling power of the skidder or dozer.
• to reach into an area where a skidder or dozer cannot
go.
• to make lift functions available when special attachments
are installed.
The winch has hydraulic clutches that are similar to a
hydraulic (powershift) transmission. The dozer or skidder
has a power take-off (PTO) that is used to connect the
power from the engine to the winch. The SCH (Self
Contained Hydraulics) on the winch label indicates that
the hydraulic system for control of the winch is inside of
the winch case. When the PTO is operating, a hydraulic
pump in the winch case takes hydraulic oil from the
winch sump and sends it to the hydraulic control valve.
The hydraulic valve controls the operation of the winch.

General

Removable covers on the winch case allow access for
repairs and adjustments.
When PTO is rotating, the hydraulic pump shaft is also
rotating. Oil from the hydraulic pump is used to cool
and lubricate the winch components. The pressure is
connected via gears to an oil clutch for the LINE-IN (power
forward) operation and another oil clutch for the LINE-OUT
(power reverse) direction.
The power through the winch to the drum for the wire rope
is controlled by a LINE-IN and a LINE-OUT clutch. When
the LINE-IN clutch is applied, the drum rotates to pull the
wire rope into the winch. When the LINE-OUT clutch is
applied, the drum rotates to reel the wire rope from the
winch at the speed controlled by the engine rpm.
When the control lever is in the BRAKE-ON position, the
oil brake is automatically applied by a spring to hold the
drum in its position. If the control lever is moved to apply
one of the clutches, the brake is released by the same oil
pressure that applies the clutch. In the event that hydraulic
power is lost, the brake remains applied and the winch
will not turn.
General
1