The oil seals on both sides of the power cylinder
are for the prevention of leakage of the high
pressure fluid which acts on the piston. Always
use new oil seals when reassembling and be
very careful not to scratch or damage them.
Because of the high pressure, even the slightest
scratch will cause fluid leakage, resulting in an
inoperative power steering system.
Also, be very careful not to scratch the sliding
portion of the rack which makes contact with the
oil seals. When removing the rack ends from the
rack, it is very easy to cause a burr when hold-
ing the tip of the rack with a wrench. Therefore,
before assembling the rack, first check the tip for
burrs and remove any with an oil stone.
Teflon rings are used for the piston and control
valve. These teflon rings are highly durable
against wear, but if it is necessary to replace
them, be careful not to stretch the new ones.
After installing a teflon ring into its groove, snug
it down into the groove before assembly of the
cylinder or housing to prevent possible damage. The functional parts of the pump which produce
fluid pressure are the cam ring, rotor and vanes,
and these should be checked for wear. If the clear-
ance between each is not within standard when
reassembling, any worn parts should be replaced.
In this case, the replaced cam ring and rotor
should be of the same length (have the same
mark), and the vanes should be replaced with
those having a length corresponding to that mark,
otherwise the proper thrust clearance cannot be
obtained. If there is too much thrust clearance,
there will be insufficient fluid pressure at low
speeds. If there is too little thrust clearance, it may
result in seizure of the vanes.The clearance between the flow control valve and
pump body installation hole is very important. After
manufacture, the factory measures the size of the
installation hole and outer circumference of the flow
control valve, and punches a mark accordingly.
Therefore, when replacing the flow control valve, be
sure to do so with one having the same mark in or-
der to insure the proper clearance.GEAR HOUSING
If the gear housing is secured directly in a vise
during overhaul, there is danger of deforming it,
so always first secure it in the SST provided
(rack &
pinion steering rack housing stand) before plac-
ing it in the vise.
± STEERINGPower Steering (Description)SR±20
