SOLVED. Steering gear question

My PS pump was leaking at the seal. So I changed the pump and the lines. I taped off the ends of the lines to prevent dirt entry while running them, did the bleed procedure, used new fluid, etc. but had no power steering at all at the end of the job. The pump was flowing a decent stream out of the return, there's no noise or growling,, but I don't have the proper gauge and adapters to measure the high pressure output. I took it back to the store, got a replacement, installed that, went through all the rigamarole but still no power steering.

The only thing I can figure is that something somehow must have got in a line despite my precautions and now it's jamming  the control valve in the steering gear box.

Looking at it, I think what has to happen is:

1. shift ABS motor & remove lines
2. pull back plastic shroud around input shaft.
3. remove bolt and pull intermediate shaft back out of coupler.
4. remove pitman arm nut, & pull arm off output shaft
5. remove 3 bolts through frame and gear box should be free.

For those that have actually changed the steering gear box on one of these, any surprises? EG: Will it clear the stabilizer bar or does that need to be removed too?

I see Rock Auto lists 2 different AC Delco units, one for non-variable effort steering, one for VES. No other brand lists a VES version. Is there really a difference? I thought it was all in the pump control valve and the pressure sensor in the line. I don't even see any difference mentioned in the FSM. What am I missing there?

I do not know if there is a difference between the VES and non-VES version, but I do not think there is. The box will come out without moving/removing the ABS box. You can get to the lines through the wheel well, under the wheelhouse (15mm). I think it is easier to remove and reinstall the Pittman arm with the box out of the car (use an impact wrench), it makes a good handle when carrying the box, as well. You will probably meet with a good amount of resistance when retracting the intermediate shaft. I usually pry it away with a huge screw driver, then put a wrench over the splined shaft to act like a spacer. This may require 2-3 wrenches to get enough thickness to get the shaft off of the splines. There is a 1/2 inch alignment pin on the end of the splined shaft that you have to clear before you can get the shaft out of the way. Clearance for the stud that attaches the top to the ABS mount is a little bit difficult to get past the mount, but will come out. You do not have to remove the anti roll bar.

Thanks Fred.

Update: I changed the steering gear box, and, while slightly better, it's still not right. I'm really scratching my head now. I've bled it manually, I've power bled it. I even made up an adapter and vacuum bled it. So it can't be air in the system. New hoses, new pump, new steering gear -- there's nothing left to change! So I'm back to suspecting the rebuilt pump(s), but I just can't believe they'd ship two bad ones in a row. I'm going to have to source a power steering pressure gauge and appropriate adapters.

I wonder if they are shipping these pumps with the right pressure control valve & spring? Other than that, I'm out of ideas. If anyone has any inspiration, I'm listening!

Fred:

Changing the steering box was actually easier than changing the pump. The hardest part was getting the Pitman arm off the old one. I had so much tension on the puller I was afraid it would either break the puller arm or strip the bolt, so I put the torch to it with the puller under tension. Once she got nice and hot there was a sudden "ping" and it popped off.

It turns out that the 95 ABS motor is mounted to the steering box so it had to be moved anyway. Perhaps not something you want to do if the brake lines are old and rusty, but then, if they are that fragile it's probably a good idea to replace them anyway. Mine are 2 years old:




So I went at the lines from above again. With a crow's foot wrench on a long extension, both lines can be readily removed with greater ease than going at them from underneath and through the wheel well:



The coupling slid off the input shaft quite easily. But I cheated -- I used a hydraulic spreader. I stuck it between the gear box and the coupling to push it off, and between the frame and the coupling to push it on. Easy-peasy if you have the tool. I bought this kit years ago for about $100 and have used it for everything from body work to re-leveling the boathouse. Very handy:

Oddly enough, I just got the latest Princess Auto flyer and the above kit is going on sale for $109 (regularly $169). Good deal for Canadians.

A further update to my problem: I took the gear box core back to the parts store today and the counter guy took a fair bit of time to try and look into this. One of their delivery guys is a retired mechanic and he also got involved. The consensus of all is that it's the pump. Again. I suspect a batch were rebuilt wrong. He went looking for a new AC Delco pump, found they were discontinued, but managed to find (possibly the last) one in Memphis Tennessee. So I have a new pump coming -- in about 4 or 5 days.

Ok, short tale: I screwed up and installed one of the o-rings on the VES solenoid in the wrong groove, then repeated my error with each subsequent pump.

Long version: I installed the AC Delco pump and had virtually the same results. I flushed, I bled, I let it sit overnight and did it all again -- to no avail. No difference with the VES unplugged at the pump.

I bench-tested the solenoid, confirming that it did go "click" and restrict the flow of air blown through the valve when I applied 12v, then open up again when the power was removed.

I measured the old control valve against the one that came with the pump and found it to be 1/10,000" larger, but the old spring was heavier gauge wire (.052" vs .049"), with one more coil and .2" longer. It was 25% stiffer than the replacement according to my postal scale. So I tried the old spring and valve and while it did make a noticeable difference, it still wasn't right. I now had partial power steering.

I made up my own pressure test rig with a 3 way valve and 2,000psi gauge and installed it in the return line with a barb fitting and fuel line hose clamp. The pressure maxed out at 175 psi (should be 1,000 psi minimum).

I called the tech support number that came with the pump, but they never answered that line. The parts store got another number from their supplier, and after playing the touch-tone lottery for a while I finally got to talk to a real person, who did seem to be somewhat knowledgeable, but admitted that Delco purges all tech bulletins for vehicles older than 10 years. We walked through every detail and he concluded that there was something wrong with the VES solenoid.

Which is no longer available. He did say his computer shows they have 75 remanufactured pumps in stock with the valve installed though. $40 more (dealer cost) than without the valve installed. He gave me the part number and I forwarded that to my guy at the parts store. He called every possible supplier and everyone told him there is no such stockpile. He did, however, discover that Cardone had an equivalent available. For another $300. Ouch.

At this point, I decided to strip it out yet again and have another close look at the solenoid. There are 3 o-rings that must be replaced, and a number of grooves they can go in. Two are obvious, the o-rings won't fit anywhere else. The last to be installed (the smallest diameter) is a nice fit in two of the grooves. I had it installed in the groove next to the threads. I thought that's were the old one was, and it seems to make sense to seal the threads. The other seemed to line up with an oil passage in the pump body. However, on careful measurement it turns out that the groove I had installed the o-ring in is the one that is closer to lining up. I swapped the o-ring to the second groove from the threads and reassembled everything. Yet again. (I'm on a first-name basis with the bolts on this thing and I think I heard one of them invite the wrench over for supper next week.)

I installed my jury-rigged pressure test setup, bled and flushed the lines once more and started the engine. No-load flow looked similar to before, but as I slowly closed the test valve, the pressure shot up past the 200psi mark. The barb fitting blew out of the return line at 800psi, so I can't say exactly what the max pressure is, but I can now again spin the wheel easily with one finger with the weight on the wheels and the car stationary.

So I wasted almost 3 weeks, unnecessarily replaced the steering gear and churned through over 2 gallons of power steering fluid because of my own stupidity. Ooops.

Sh1t happens,..

Goes to show no such thing as a free education...