Description And Operation - Jeep J-10 Series 1982 Technical & Service Manual

2L-i
POWER STEERING
GEAR AND PUMP
SECTION INDEX
General Information 2L-1
Power Steering Gear 2L-19
Power Steering Pump
Tools
2L-37
2L-45
GENERAL INFORMATION
Description and Operation 2L-1
General 2L-1
Hydraulic Pressure Test 2L-15
Leak Diagnosis 2L-10
GENERAL
The power steering system consists of a power steer
ing gear, hydraulic pump, and interconnecting hoses.
The system fluid supply is contained in a reservoir
mounted on the pump. Fluid from the pump is supplied
to the gear through the interconnecting pressure and
return hoses. The pump is operated by a drive belt
mounted on pulleys attached to the pump shaft and
engine crankshaft.
Two different ratio steering gear units are used. CJ
and Scrambler models use a constant ratio gear with a
17.5:1 steering ratio. Cherokee, Wagoneer and Truck
models use a variable ratio gear with a 16:1 ratio on
center and 13:1 ratio at full lock.
Although the steering ratios of the two units differ,
exterior appearance and service procedures for both
units are the same. However, the internal components of
the two gears are not interchangeable.
A vane-type power steering pump with a combination
flow control/relief valve is used on all models. Two valve
calibrations are used. On CJ and Scrambler models, the
valve is calibrated to open at 1100 psi (7 584 kPa). On
Cherokee, Wagoneer and Truck models, the valve is cali
brated to open at 1500 psi (10 342 kPa).
The power steering gear is designed to operate man
ually if a system malfunction should ever occur. This
feature provides the driver with continued steering con
trol of the vehicle. In this condition, the gear operates
Periodic Maintenance 2L-15
Service Diagnosis 2L-6
Specifications 2L-18
like a manual steering gear; hydraulic fluid is bypassed
through the gear valve body to allow manual operation.
NOTE: The power steering gear and pump form a
closed system. Contaminants or foreign material must
not be allowed to enter the system at any point. Ifeither
the gear or pump become contaminated, or incur dam
age extensive enough to produce debris, both com
ponents must be disassembled, cleaned, and serviced.
DESCRIPTION AND OPERATION
Steering Gear
The power steering gear is a recirculating ball-type
unit (fig. 2L-1). Steel ball bearings act as a rolling thread
between the steering gear wormshaft and rack piston.
Two different ratio gears are used. CJ and Scrambler
models use a constant ratio gear with 17.5:1 steering
ratio. Cherokee, Wagoneer and Truck models use a vari
able ratio gear with 16:1 steering ratio on center and 13:1
at full lock. Although the two gears have different steer
ing ratios, exterior appearance, diagnosis, and service
procedures are the same for both.
Steering gear wormshaft fore and aft thrust is con
trolled by a bearing and two races at the lower end, and
a bearing assembly in the adjuster plug at the upper
end. The lower bearing races are conical in shape. This
design maintains constant preload on the wormshaft to