Steering Rack Query
Posted: Thu Nov 16, 2017 12:31 pm
I have just removed my +2 steering rack to check the pinion pre-load, as I have a theory that this is important to minimise sensitivity to front wheel imbalance.
As expected, instead of 2lbs at 8 inches to turn the pinion, it's 10 oz at the straight ahead position, and 1lb 3 oz at the extremes of the rack.
OK, but I have a question about how you set up the preload correctly. Reading the workshop manual we have:
Para. 3
a) Fit the plunger and cap nut to the pinion housing. Tighten.the nut to eliminate all end float and, using feeler gauges, measure the clearance between the nut and housing as shown on Fig. 15. Remove the cap nut and plunger.
b) Make up a shim pack equal to the cap nut to housing clearance, plus .004 in
c) Pack the unit with grease and assemble the cap nut, shim pack, spring and plunger to the housing and tighten the cap nut.
So this sets the distance between the cap nut and the plunger, assuming that the spring rate of the spring is correct for the right preload. So if the spring is a bit tired, then the preload will be too light and there is no way to adjust it unless I replace the spring. Have I got that right?
Dave Chapman.
As expected, instead of 2lbs at 8 inches to turn the pinion, it's 10 oz at the straight ahead position, and 1lb 3 oz at the extremes of the rack.
OK, but I have a question about how you set up the preload correctly. Reading the workshop manual we have:
Para. 3
a) Fit the plunger and cap nut to the pinion housing. Tighten.the nut to eliminate all end float and, using feeler gauges, measure the clearance between the nut and housing as shown on Fig. 15. Remove the cap nut and plunger.
b) Make up a shim pack equal to the cap nut to housing clearance, plus .004 in
c) Pack the unit with grease and assemble the cap nut, shim pack, spring and plunger to the housing and tighten the cap nut.
So this sets the distance between the cap nut and the plunger, assuming that the spring rate of the spring is correct for the right preload. So if the spring is a bit tired, then the preload will be too light and there is no way to adjust it unless I replace the spring. Have I got that right?
Dave Chapman.