Earlier cars have a steering box mounted on the front axle, 1302 (and 1302S) have the box mounted on the bodywork and the 1303 is fitted with rack and pinion steering again, mounted on the bodywork.
During a restoration, check the condition of the steering damper by pulling and pushing its arm in and out; if extra or less resistance is felt at any point in the travel, replace the damper. Also, feel for lost steering wheel movement; that is, movement of the perimeter of the steering wheel in excess of 1 in. which does not also turn the front wheels. If this is discovered, check whether there is play in any of the joints, including the track rod ends, before turning your attention to the steering box or rack.
In the case of the steering box, play between the worm and spindle axle can be dealt with by adjusting the screw (turn the steering to full lock and slacken the locknut first) on the front of the unit whilst the spindle is moved from side to side. If this fails to reduce void movement to the recommended level, the roller/worm play will have to be reduced.
Steering boxes can be adjusted to take up this void movement by slackening off the lock nut on the top of the unit, adjusting the screw (don't tighten it right up, but screw it in just until slight resistance is felt), then hold it in that position and tighten the locknut. Check that the steering is not tight before using the car on the road and, if it is, re-adjust the screw. If there is still too much void steering wheel travel, it is best to exchange the steering box.
The components of the worm and roller steering box. (Courtesy Autodata)
With steering racks, adjust the bolt situated under the rubber bung in the spare wheel well until it can just be felt to contact the thrust bearing — slackening then retightening the locknut accordingly.