Apparently I suck at rebuilding a steering box.

[cdoggwsu]

So the steering box (along with the PS pump and hoses) on my '88 Blazer was leaking severely so I figured I'd save some money on a reman'd one (180 bucks at schucks) and pick up a full rebuild kit from West Texas Off-Road for a more reasonable $45. After tearing the box down and replacing everything I figured I'd reduce any more possible problems by taking the box down to the chevy dealership and having them set the over center and input shaft preload.

Well the first time I dropped it by the shop called shortly after and said that the input shaft wasn't lining up properly so I picked it up, cracked it open and found a few of the little ball bearings had fallen out of the worm shaft track. So after putting it back together and following every step in the shop manual was able to get it back to them and they got it all set. I bench tested it for tightness and correct centering, everything looked good and I bolted it up adding an ORD bolt in brace along with a new PS pump, lines, a magnefine filter and a new drag link.

I bled it no problem but there was still a serious amount of play in the steering wheel to the tune of almost 90 degrees in both directions and it was so hard to turn it felt like there was no power steering at all. After checking everything I come to find that all of the play is in the input shaft and by turning the steering shaft (XJ swap) by hand I can see the input shaft is actually moving IN and OUT a little when it is turned.

Could this be from the shop not setting the input shaft preload correctly, or did I screw up again on getting the ball bearings installed? Is there something I'm missing about how those bearings are dropped in or what? I'm totally fed up at this point and considering just buying a reman'd box even though I'm already into this one about 90 bucks. Aside from going all out on a PSC or AGR box that probably won't see crossover or hydro assist for quite some time, are there any other options for "upgraded" boxes?

FWIW, the tech at chevy (a pretty knowledgeable guy) told me they don't even bother rebuilding them by hand anymore as it's easier to just swap them for a reman.

 

[73k5blazer]

The reman ones can suck too. They are difficult to build properly. And once built, it really requires this huge machine to set the pre-load along with several other important adjustments properly. The kits I've seen have sloppy tolerances on some of the components.

It sucks, there's no good answer besides one from a yard that's in working order or a properly built new one.

I explain better in post #11 here, but a good whole thread for you

...

 

[4X4HIGH]

I've rebuilt several steering boxes now and it really is easy as long as you get the balls installed correctly and get the input preload and sector shaft adjustments set correctly. You do know that the 24 steel balls have 2 different sizes? They are only .0005-.001" difference and "usually" they are different colors (one is more black while the others are more a shiny silver). These balls must be alternated when installed (one large, then small, then large and so on until they are all installed).

When i rebuild them i automatically drill and tap them for hydro assist.

Forgot to mention that all the "rebuilt" steering boxes i've seen are either not put together correctly or the case is bad. Not worth spending the money on a rebuilt box IMHO.

 

[cdoggwsu]

Yep the ball bearings were light and dark. I followed the GM service manual to the letter, dropping the balls in the bottom hole while turning the worm shaft counterclockwise.

That may not even be the problem, but whatever the cause it's allowing the input shaft to move in and out of the box. I don't know if the adjuster plug not being seated all the way would allow that much play in the input shaft or not.

 

[4X4HIGH]

The spool valve has a pin that needs to be aligned properly or the adjuster nut can't be tightened properly. This could be your problem.

 

[cdoggwsu]

You're talking about red arrow in the attached pic, right? Does that just line up with the valve body or does it push in and turn to "lock" in? I don't have the manual in front of me but I seem to remember it saying push in and turn which I'm pretty sure I did, although that would explain the in and out play in the input shaft...I guess it's back out of the truck tonite to see what the deal is. It's a good thing I didn't use red loctite on the box bolts...

 

[4X4HIGH]

Yes, that pin has to line up with the slot in the spool valve. There should also be a large O-ring on the inside of the spool valve that the worm gear seats against.

 

[cdoggwsu]

Yep, the worm drive was seated correctly with the pin and the o-ring. The play is just in the input shaft at the area shown in blue below. It can't be pulled in and out but when the shaft is turned it pushes or pulls itself in and out in a screwing motion, like the input shaft isn't being retained correctly which makes me think the input plug wasn't torqued correctly. That should also mean that the bearings in the worm gear are still in place as they are providing the force for the screwing motion. The one caveat of that theory is that the input shaft moves about 1/2" in the outward direction as the shaft is turned counterclockwise, then it begins to catch. Even a slightly loose plug shouldn't allow for that much movement.

 

[4X4HIGH]

Yep, the worm drive was seated correctly with the pin and the o-ring. The play is just in the input shaft at the area shown in blue below. It can't be pulled in and out but when the shaft is turned it pushes or pulls itself in and out in a screwing motion, like the input shaft isn't being retained correctly which makes me think the input plug wasn't torqued correctly. That should also mean that the bearings in the worm gear are still in place as they are providing the force for the screwing motion. The one caveat of that theory is that the input shaft moves about 1/2" in the outward direction as the shaft is turned counterclockwise, then it begins to catch. Even a slightly loose plug shouldn't allow for that much movement.

The pin on the worm gear must go into the slot to the left of the red arrow. If it doesn't then the whole input shaft and inner spool valve can move in/out the distance from the back of the inner spool valve to the end of the outer spool valve.

Too bad you weren't alot closer or i would have you bring it over and i would show you what i'm talking about and how to fix it properly.

 

[cdoggwsu]

Yeah, I'll definitely make sure that everything is seated properly. I know what you're talking about, I should have mentioned the red arrow in that particular pic was already there when I found it on the web, I was just using it to illustrate where I was seeing the movement in the input shaft.

Thanks for the info, hopefully the problem will make itself evident after tearing this box apart for the third time...

 

[cdoggwsu]

So I think this box is trashed. I pulled the input shaft assembly out with the worm shaft firmly seated and the alignment pin in place. Triple checked the assembly diagrams and it is all correct.

After checking the power piston assembly it looks like for some reason the ball bearings aren't being retained correctly and it's messing with the worm shaft rotation. When I originally took the box apart (after sitting in the truck for 20+ years I would presume), there were a few small pieces of metal that came out of the ball recirculation track but after careful inspection it didn't appear to be damaged in any major way. I should have figured it out the first time when the box magically realigned itself, but I figured it was a mistake on my part.

Well it would seem that dislodging those few bits is causing the bearings to bind so I'm thinking this box is shot. Chalk one up for experience, I suppose.