85 Nissan 720 manual steering box

[Natej]

So I just recently bought a 85 720 and steering wheel has more play than I would like. I’ve looked up every where I could for a remanufactured or even a kit to rebuild mine and no luck. Does anyone know if the d21 would fit on my 85? Or has anyone retro fitted a power steering box on their 720?. Haven’t had a 720 since I was 17 and parts were a little easier to find then lol. 

[Stoffregen Motorsports]

Send it to Redhead Steering Gears in Auburn, WA and have them rebuild it. A typical rebuild from them runs between $300 and $450.

[NC85ST]

I would look for an ‘85 that’s being parted out. A lot of ‘85’s came with power steering, so it shouldn’t be too hard to find what you need, including, if I’m not mistaken, the steering column.

[Stoffregen Motorsports]

Oh, I misunderstood. I thought you were trying to have your manual box rebuilt.

[datzenmike]

23 hours ago, Natej said:

So I just recently bought a 85 720 and steering wheel has more play than I would like. I’ve looked up every where I could for a remanufactured or even a kit to rebuild mine and no luck. Does anyone know if the d21 would fit on my 85? Or has anyone retro fitted a power steering box on their 720?. Haven’t had a 720 since I was 17 and parts were a little easier to find then lol. 

 

First I would grab the steering column at the steering box and twist it back and forth. If it seems excessive there is a steering box adjustment screw. Loosen the lock nut and turn the screw CCW to tighten the gear lash. Raise the wheels off the ground and turn the steering wheel quickly lock to lock with the engine off. If there are any stiffness or tight spots your adjustment is too tight. Most wear is in the straight ahead position so when adjusted out it may be tight towards the full lock position and this must be avoided.

 

Next while the front is raised off the ground, have someone rock the steering wheel back and forth through this play area while you watch each of the 6 steering ball joints for movement input, but sloppy output passing the movement along. Grab the ball joint by hand it's easier to feel any slack. Look also at the idler arm which should be free to turn but NOT move up or down. Last are the wheels. Grab at 9 and 3 and tug lightly in and out. If there is any play then the wheel bearings are set too loose or worn and need adjusting.

 

If all of the ball joints, idler arm and wheel bearing slack is added up to a total of only 1/8" it is multiplied about 19 times by the steering box ratio and amounts to 2 3/4" of steering wheel play.

 

If the wear is in the ball joints the expense of a replacement box will not fix this.

[Stinky]

A PS box has a dif column.

 

I know this because I went from MS to PS....I may still have the box.

[datzenmike]

The PS box is longer so a shorter column is needed. Tilt steering columns are also different.

[Stoffregen Motorsports]

On a 720, the column, or more accurately, the steering shaft, is collapsible, so he can probably get away with using the one in the truck. What might be a propblem is the spline count and diameter of the input shaft on the box. I bet they are different between PS and manual boxes.