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Steering CHAPTER 9.1
ball bearings 2 and 3, the lock-nut must be loosened and
the sealing housing cover re-tightened.
Only a few standard design larger saloons can be found
on the road with manual recirculating ball steering. For
reasons of comfort, newer passenger cars of this type have
hydraulic power-assisted steering. The same applies to
commercial vehicles; only a few light vans are still fitted
with manual configurations as standard and even these are
available with power-assisted steering as an option.
Fig. 9.1-14 Lemfo ¨ rder Fahrwerktechnik pre-lubricated tie rod
joint, used on passenger cars and light vans. The joint housing 1
has a fine thread on the shaft (M14 1.5 to M22 1.5) and is 9.1.4 Power steering systems
made of annealed steel C35V; surface-hardenable steel 41Cr4V is
used for the ball pivot 2.
The actual bearing element – the one-part snap-on shell 3 made Power steering systems have become more and more
from polyacetal (e.g. DELRIN, made by Dupont) – surrounds the widely used in the last few years, due to the increasing
ball; the rolled-in panel cover 4 ensures a dirt- and waterproof
seal. The polyurethane or rubber sealing gaiter 5 is held against front axle loads of vehicles on the one hand and the
the housing by the tension ring 6. The gaiter has a bead at trend towards vehicles with more agile steering prop-
the bottom (which the second tension ring 7 presses against the erties and hence direct transmission steering systems on
spigot) and a sealing lip, which comes into contact with the the other. With the exception of some members of the
steering arm. ‘sub-compact’ class, power steering systems are op-
The ball pivot 2 has the normal 1:10 taper and a split pin hole
(position 8). If there is a slit or a hexagonal socket (with which tionally or automatically included as one of the standard
the spigot can be held to stop it twisting), a self-locking nut can features.
be used instead of a slotted castle nut and split pin. Manual steering systems are used as a basis for power
steering systems, with the advantage that the mechani-
slightly angular arrangement of the gearing can be seen cal connection between the steering wheel and the
top right. This is necessary for alignment bolt 1 to over- wheel and all the components continues to be main-
come the play of the wheels when pointing straight tained with or without the help of the auxiliary power.
ahead, by axial adjustment. If play occurs in the angular The steering-wheel torque applied by the driver is
Fig. 9.1-15 Mercedes Benz recirculating ball steering suitable for passenger cars and light vans; today, apart from in a few exceptional
cases, this is only fitted as a hydraulic power-assisted version. Pitman arm 9 is mounted onto the tapered toothed profile with a
slotted castle nut 11 (Fig. 9.1-24).
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