620 Steering box adjustable?

[BitBandit]

So i just failed safety because my steering box was "loose" is there a way to tighten this up or do i need to go try and find a box that's not loose?

[Z-train]

There is SOME adjustment.Odds are it's long gone,though.

[BitBandit]

That is what I was figuring, thanks for the info, guess i will be going to the junkyard and hoping that the 620 there has a good box.

[datzenmike]

Well first the, 620 box has a steering ratio of 19 to 1 so if all the steering ball joints, 6? I think??, have a combined slop of just 1/8" there will be about almost 2.4" of play at the steering wheel end. Just saying, that if there is wear in the rest of the steering, adjusting the box won't help.

 

Steering box wear tends to be in the straight ahead position with less to either side at full turn. If you should remove the wear clearance in the center the steering can be tight and jam when turning. Not good. A tight box will only accelerate other parts wear in the box.

 

On the top of the 620 steering box is a filler plug, usually soft nylon. Beside it is a set screw with a lock nut. Hold the set screw with a screwdriver and loosen the lock nut several turns. Raise both wheels off the ground. With screwdriver turn set screw counter clockwise to reduce clearance between sector shaft and the worm assembly and LIGHTLY engage it. Don't force. Snug the lock nut while holding set screw in place. Turn steering wheel lock to lock looking for ANY snug or tight spots. If tight at any place in the turn, loosen the lock nut and turn the set screw clockwise slightly and test for tight spots again. Keep adjusting until steering wheel turns freely side to side through the full turn.Tighten the lock nut and test one last time. Top up box with GL-4 transmission oil, leave space at top.

[BitBandit]

I will give that a try before I head the junkyard, thanks Mike.

[620Soldier]

Ho man. Same boat hear. Well, not the safety issue. But I got around 5-6 inches of play in the wheel before engaging wither direction. I do have a steering box to replace it with, but is there any other obvious wear to look for in the rest of the linkage between the rubber wheels and steering wheel?

[crackerjack69]

Check center drag-link ball joints and tie rods for damage or play. I imagine the FSM would have a good recommended inspection procedure.

 

Yah Mike, 2 on each tie-rod, and 2 on the drag-link.

 

Possible you could also find fault w/ the idler arm, so don't forget to check that. Those are fairly inexpensive new.

[crackerjack69]

Best to diagnose before you go shopping...

[skyshadow]

I know this is a old thread, but better to revive then start new. What's a good alternative steering box if the stock is toast? When installing my CA18DET, one of my buddies literally ripped the steering apart. There is no way mine will go back together and work. SOOOO, Any ideas on alternatives? I actually would be interested in staying with manual steering, race Dat

[datzenmike]

Find another 620 and replace it. There is no easy or cheap method that will work as well as the original.

[MikeRL411]

Well first the, 620 box has a steering ratio of 19 to 1 so if all the steering ball joints, 6? I think??, have a combined slop of just 1/8" there will be about almost 2.4" of play at the steering wheel end. Just saying, that if there is wear in the rest of the steering, adjusting the box won't help.

 

Steering box wear tends to be in the straight ahead position with less to either side at full turn. If you should remove the wear clearance in the center the steering can be tight and jam when turning. Not good. A tight box will only accelerate other parts wear in the box.

 

On the top of the 620 steering box is a filler plug, usually soft nylon. Beside it is a set screw with a lock nut. Hold the set screw with a screwdriver and loosen the lock nut several turns. Raise both wheels off the ground. With screwdriver turn set screw counter clockwise to reduce clearance between sector shaft and the worm assembly and LIGHTLY engage it. Don't force. Snug the lock nut while holding set screw in place. Turn steering wheel lock to lock looking for ANY snug or tight spots. If tight at any place in the turn, loosen the lock nut and turn the set screw clockwise slightly and test for tight spots again. Keep adjusting until steering wheel turns freely side to side through the full turn.Tighten the lock nut and test one last time. Top up box with GL-4 transmission oil, leave space at top.

 

This is a version of the General Motors "Saginaw Screw Jack" which is so basically reliable that it is used to raise and lower the Personnel Access Hatch of the Minuteman 3 missile silos.  Only one caution, if you use a power drive to open [like lazy crews on a very cols winters night] , the hardened steel balls will brinnell the spiral worm and cause failure of the screw jack track due to seizure of the track. The steel balls settle into the depressions caused by impact of the hardened balls against the relatively softer spiral tracks. Shouldn't have that problem in automotive use unless you try to steer beyond the "stop" limits of steering like in autocross.

[Scgreen620]

If I remember mklots? (Not sure if that's how you spell it" but he has a video on you tube on how to adjust that

[datzenmike]

There is some adjustment for wear... BUT.... as the wear is not even across the entire lock to lock turning, but concentrated mostly in the ahead position, If you reduce the gear lash or play in this area the steering will be too tight the farther you turn off center. The last thing you want is to turn, and have the wheel not return properly.

 

If you do adjust the play, do so with both wheels off the ground and quickly turn lock to lock looking for any tight spots.

 

 

 

Lets examine your claim it is 'toast'. If you mean severe side to side movement of the wheel and very little actual turning of the vehicle, perhaps all the ball joints and idler arm have wear and this explains the sloppiness.