1972 Steering box replacement - Any tips?

[snowblind]

Hi everyone.

I'm going to replace my PS box this weekend. Anyone have any tips?

Any need to pre-fill the box with fluid or do I just top up the PS pump?

Thanks in advance.

[storm9c1]

Originally Posted by snowblind

Hi everyone.

I'm going to replace my PS box this weekend. Anyone have any tips?

Any need to pre-fill the box with fluid or do I just top up the PS pump?

Thanks in advance.

Doesn't matter if you Install it partially filled. Installing it completely full is messy and nearly impossible.

Then there is a proper bleeding procedure you need to do:

(various service manuals for various years cars and trucks have some variation of this procedure)

The vehicle is supposed to be raised until the front wheels are off the ground, with the engine OFF, turn the steering wheel from stop to stop at least 30 cycles. This will force out the air bubbles into the reservoir. Be sure to check the level a few times. Then start the vehicle and repeat -- 30 times, stop to stop. If the pump is noisy or the fluid is very milky, shut it off and wait 10 minutes. Then repeat the process from the beginning until the fluid looks clear and the steering feels correct. Be sure to drive it carefully on the first test drive in case there are still some bubbles or something wrong with the box.

[snowblind]

Originally Posted by storm9c1

Then there is a proper bleeding procedure you need to do:

(various service manuals for various years cars and trucks have some variation of this procedure)

The vehicle is supposed to be raised until the front wheels are off the ground, with the engine OFF, turn the steering wheel from stop to stop at least 30 cycles.

Thanks for the feedback.

I have heard of turning lock to lock a few times with the wheels up to bleed the system but that was with the engine on. 30 times with the engine off and I'm going to have forearms like Popeye!

[BHyatt]

Make sure your steering wheel stays aligned properly when putting everything back together.

[OhOneWS6]

When I had mine off to replace the seals I put one bolt back in the gear from the opposite side temporarily. This makes the threads stick out thorough the side that contacts the frame like a stud. I was then able to line the gear up with this bolt and let it hold the weight while I started the other bolts. Once the other bolts were started I removed the first bolt and put it in the correct way. This made it much easier to install the gear. I didn't have to wrestle that first bolt in from the other side of the frame while trying to hold the gear in place.

[Wrenchbender Ret]

Good tip Wise one.

[cdowns]

when changing steering boxes alwys check your frame area goog it's not unusual to find stress cracks sometimes at the box mount area

[passthebuck]

Use a good synthetic powersteering fluid. Once it's in there, it never gets changed so you might as well use the good stuff.

[longhorn70gmc]

I am currently doing mine.
First, save the the rag joint and ensure the spline matches the new power steering box spline. This has held me up for 3 weeks now. I am good now. Next make sure your pitman arm matches the new box spline, so it fits. I was told to install it after the box, but I would have been better installing it before the box going on. Just make sure the pitman arm matches up right where your turn radious is good to go because installing it wrong can cause issues for your turn radious. Fortunently I am strong enough to hold that box up there long enough to get one or two bolts started, but the other trick the other guy stated is a great ideal where you put one in backward to start the others then go back and fix it right. Good luck, Unfortunently I have to do this again soon on my other truck.
R/
Billy

[snowblind]

OK. I took a couple of days longer than expected but not a terrible job.

Everything came off pretty easy except the PS fluid return line. The flare nut was seized to the pipe and just twisted it all up. This delayed me two days so I would recommend ordering a set of replacement hoses BEFORE starting the job.

The orientation of the rag joint and the various flats/splines on the rag and pitman makes it very easy to line up the steering to straight. I was worried about this but it was no problem.

I had my wife help hold the box stable while I supported the weight and did the bolts from underneath. This worked well. I kept the bolts loose until I got everything connected and then tightened it down.

The advise about cycling the box with the engine off is correct and very easy to do when the front wheels are off the ground! You need to cycle it to suck/pump the fluid from the res into the box. You fill the res and then as soon as you turn it a little is goes glug... glug... into the box and then you add some more fluid. I repeated a bunch of times until the res was full and it stopped burping. Then I did it a bunch with the engine on.

End result - Everything is great. New steering box is tight and doesn't leak fluid. Mission accomplished.