Been a while since I messed with a 245 steering box so bear with me. I think you have an adjustment on the gearbox for taking up backlash on the gears. Should be a threaded rod with a screwdriver slot and a jamnut. Loosen the jam nut and turn the rod counter clock wise and see if that takes the play out. Don't make it too tight, just enough to take out the play. There is also a possibility that the lower bearing/bushing is worn in the box. The water usually sneaks in down the shaft from the steering wheel. Espescially if the steering wheel center cover is missing. Anyway, taking up the backlash is usually a temporary fix due to wear in the gears. It's usually more cost effective just to replace the entire steering box if it is worn to this point.