another 521 steering gear?

[140ypower]

hey, I've lost my Datsun 521 steering gear box. okay Datsun 620 steering device? or from another Datsun?

[K_trip]

- removed -

[datzenmike]

The 521 and the 620 share the same sector shaft but the box is a different number. The worm gear bearing is the same. I guess some of the internal parts are the same.

[socaldatsun]

yeah 521 and 620 gear box is the same. I swapped mine out for a 620 one not too long ago.

[140ypower]

okay, must, therefore, look for 620 with a control gear :) the previous owner lost when extracting the car ..

[datzenmike]

This is good to know. While I'm not convinced that they are identical they may be a perfect swap. Some part numbers are different between them though. Swap the whole thing.

[DanielC]

I think a lot of parts on the early 620 trucks are pretty much the same, except for a change from SAE (inches) to metric measurements.

For example, a rear wheel cylinder for a 521 will be held to the backing plate by 5/16-24 threaded nuts.  On a 620, the nuts were M8-1.25.  in a similar fashion, the flare nut on the cylinder went from a 3/8-24 thread to a M10-1.0 thread.

[140ypower]

I bought a 620 from a steering gear box and it fit 521  B)  thanks this helped a lot, as in Finland, there are no more spare 521 left .. :geek:

[wayno]

Score!!!  :thumbup:

[Rocket Dog]

Guys, on my 521 the steering has a lot of play in it.  I'm presuming the steering box is worn, but might the problem be in the steering gear?  I'm inclined to buy a 620 box based on this discussion here.  Rock Auto has a repair and return service for $16 bucks or so, I wonder if I should call them, explain the similarity between the 72 and 73 steering gear boxes, and see if they will repair and return my stock 521 box?

[datzenmike]

First of all be sure there isn't play in the king pins or any of the ball joints in the cross rod (2), tie rod ends (4), or the idler arm. Just 1/8" of total slack in these items is multiplied by the 521's 19:8 steering ratio and feels like almost 2.5" at the steering wheel.

 

There is an adjustment for the gear lash on top of the box. There is a screwdriver slot on a bolt top with a lock nut below it. Loosen the lock nut and turn the screw. In (clockwise) tightens up the lash.

 

NOTE Most gear wear obviously, is located in the most used position... center. With less to the L&R full turn. If you remove all slack in the center the steering may bind up on turns, something you do NOT want. So raise the wheels off the ground and after each adjustment turn lock to lock quickly. If you feel any slight tightness back you adjustment of slightly. When done tighten the lock nut and re test that this has not altered your adjustment. Running the box too tight will only accelerate the wear sooner.

[Rocket Dog]

Mike, I presume the red arrow points to the lock nut, and the yellow arrow is the gear lash adjustment?

 

[DanielC]

Red arrow points to lock nut.  Then the screw inside the lock nut can turn.

 

Yellow arrow, oil fill plug.  90 weight gear lube.

[ggzilla]

Only tighten it finger tight. Zero torque.

[Rocket Dog]

Aye aye, so the screw inside the locknut is the lash adjustment?  Raise the front end of the truck up, make slight adjustments then turn full left and right rudder to make sure there's no binding in the steering?

[wayno]

I would suggest that you take a photo of where it was at before making any adjustments, so that it can be put back if needed.

I personally have never heard of anyone adjusting these steering boxes and being happy, when they are worn out, they are worn out. :(

[ggzilla]

I have been happy with adjustment. It doesn't fix worn steering linkage, and doesn't make it like new, but makes it a bit better.

[Rocket Dog]

Okay well.  Not trying to make this too hard, but my first inclination was to just change out the box.  I don't know it's history, etc. I appreciate understanding how to adjust it, but all things considered I think I'll just replace it with a new(er) steering box.

 

* EDIT *

 

Rock Auto lists a steering gear for the 73 620 truck.  It's a rebuild service for about $163 bucks.  The company that does the work is Lares Corporation in MN.  Their number is 800-555-0767.  I called them and they advised me that rebuilding a 521 steering box was not a big deal, they rebuild much older boxes and this one isn't much of a challenge for them.  I'll give it a shot and let you all know.

[wayno]

Okay well.  Not trying to make this too hard, but my first inclination was to just change out the box.  I don't know it's history, etc. I appreciate understanding how to adjust it, but all things considered I think I'll just replace it with a new(er) steering box.

 

* EDIT *

 

Rock Auto lists a steering gear for the 73 620 truck.  It's a rebuild service for about $163 bucks.  The company that does the work is Lares Corporation in MN.  Their number is 800-555-0767.  I called them and they advised me that rebuilding a 521 steering box was not a big deal, they rebuild much older boxes and this one isn't much of a challenge for them.  I'll give it a shot and let you all know.

 

I did not mean to scare you away from trying to adjust your steering gear,  try to adjust it, who knows, it may turn out fine, just don't expect a miracle.

[Rocket Dog]

I did not mean to scare you away from trying to adjust your steering gear,  try to adjust it, who knows, it may turn out fine, just don't expect a miracle.

It's all good.  I don't know the history of the steering box, but most likely it's been doing it's thing for over 40 years.  Anyway, it's just steering.  Not like thats a critical function anyway.

And with tighter steering I can concentrate better on my texting.