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SPC Adaptor Fitting Instructions (Bishop Cam Steering Box)


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The SPC (Steering Play Control) Adaptor has been developed to reduce the amount of steering play which can appear as a result of wear between the worm and peg arrangement. The adaptor is designed to reduce steering wheel play, help maintain a good straight line driving position and improve steering when cornering.


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, click again to close)

There are marginal differences between some steering boxes. Not all sector shaft arms have dimples. (see dimple in fig. 1). If your unit has no dimple then one will need to be machined in by a specialist.

If your sector shaft has only a very small dimple (similar to a punch mark) then remove the sector shaft and use a 4mm diameter drill bit to marginally enlarge the dimple in order to allow the captive ball bearing in the SPC Adaptor to locate. The hole should be no deeper than 1.5mm.

Finally, please note that this Adaptor cannot work miracles on badly worn boxes. Before fitting, please ensure that the steering system has no existing faults or is excessively worn. If you require your steering box overhauling then we are happy to recommend a Bishop Cam Specialist to undertake this work.

To ensure best results and providing the above issues have been addressed, we recommend fitting as follows;

Step 1 - Jack up the car so the wheels are just clear of the ground

Step 2 - Turn the steering wheel to extreme opposite locks ensuring there are no rough points to the steering box operation.

Step 3 - Centre the steering wheel. Remove the top of the steering box (3 bolts) making sure to retain all shims for use with fitting the SPC Adaptor.

Step 4 - With the wheels in a straight ahead position, place the adaptor on the box locating the captive spring loaded ball bearing (shown in fig. 2) into the sector arm dimple (fig. 1). Visually check that the 3 bolt holes line up by pressing down against the spring loaded ball. There can be marginal variation between steering boxes. The Adaptor spring tensioning bolt can be temporarily released to assist. If the 3 holes do not correctly align then please contact us.


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, click again to close)

Step 5 - Remove the adaptor and if all is ok then replace the shims which were used with the standard top. Relocate the SPC Adaptor and bolt down lightly. Rotate the steering to a full left/right lock to ensure free movement. Tighten down bolts to increase the spring load (light torque only). Rotate steering again to check and then assuming ok, tighten all three bolts to the required torque. Undertake a final check of the steering to ensure a full free travel between locks.

Step 6 - Remove vehicle from jack.

Lubrication - The adaptor is already greased and should operate with steering box oil. However, if lubrication is required, remove the spring tensioning bolt and insert a small quantity of semi-fluid grease before refitting the bolt.




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Website last updated Mar 14 2024

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