Re: Very light steering
What sort of 164? My 12 valve V6 Lusso is actually pretty heavy (by modern car standards) - I quite like it. DEFINITELY not a job for the little finger! Has it suddenly gone liek that or was it like that when you bought it? Also, is it very vague around the straight ahead position?
Most power steerign racks of that era had a torsion bar inside the pinion housing. It's the only direct coupling betwen the column and the rack pinion. As you turn the wheel, this bar twists and opens up a rotary valve to let fluid through to whichever side of the rack needs it. There are metal stops that carry the drive to the pinion mechanically in case the torsion bar snaps. The weight of the steering is governed by the stiffness of the torsion bar. If it's very stiff, the steering will be heavy because it will only allow the sleeve velve to open a small amount before it starts turning the wheels anyway. IF the torsion bar snaps, the steering gets very light because the sleeve valve goes to full travel as the mechanical stops touch each other. Only solution is a reconditioned rack, really. (If that's wha tthe problem is!) When the engine isn't running, there should be a fair amount of play in the rack - the steerig wheel should move a few degrees before the road wheels start to turn.