Hydro assist/power steering gurus needed

YJJPWrangler

YJJPWrangler

Well-Known Member
Joined
Jul 19, 2005
Location
Charlotte
vehicle specs: 91 4.3l Chevy V6. Stock power steering pump, ported Saginaw box, 1.5” ram. I am running a cooler and the line routing goes: pressure line from pump to box, lines to ram, return line from box to cooler to pump. I ported the box myself following instructions from @XJsavage as well as billavista tech post on pirate.

I have blown out the stub shaft seal twice today while trying to pressurize the system. I have replaced the seals on the pitman arm shaft and they are holding but I keep losing the stub shaft seal/dust cover. The last time it blew, it blew the spring in the seal past the dust cover. The box is now completely blown apart and I’m going to replace every seal that I can.

This is my first time running/setting up hydro assist. Does it matter which lines from the ram hook up to the ports on the box? My understanding is that both ports are high pressure and will send fluid to the ram based on steering wheel input. Is this a correct understanding?

The Jeep is running great but I have spent most of the day soaked from head to toe in power steering fluid. I can’t pull it outside bc no power steering and if I take the belt off I can’t run it for long because no water pump. So now this box is holding me back on everything. No burrs on the inside to cut a seal etc but once the system gets to pressure it sprays from the stub shaft seal.

What am I missing?
 
It matters which line goes to which side of the ram. Assuming it’s not a forward throw pitman arm and that you tapped the box on the side and didn’t use the top or front caps, the top port is for turning left, and the bottom port is for turning right. The orientation of your ram will dictate which port is used for turning each direction.
 
Last edited:
@adamk I tapped the box on the side. It is not a forward throw arm. The ram is hard mounted to the axle and then to the drag link. If I’m understanding you correctly, the top port should be connected to the left side of the ram to turn left(it pushes the ram back into the body of the ram) and the bottom port to the right side of the ram. Could hooking them up incorrectly blow the seal out?

I just checked and my top port line was connected to the right side of the ram and the bottom port was on the left side of the ram. So I had it hooked up backwards. I think with the ram and the box fighting each other to turn, that might have caused enough pressure to blow the stub shaft seal.
 
Last edited:
Have you tried leaving one side of the ram disconnected? Leave it mounted to the axle housing, but remove the other end to see if it extends or retracts without mechanical opposition.
 
BigSouth said:
Have you tried leaving one side of the ram disconnected? Leave it mounted to the axle housing, but remove the other end to see if it extends or retracts without mechanical opposition.
Click to expand...

I haven’t. Mostly because the system had air pockets in it due to not being bleed properly bc it wouldn’t hold pressure.
 
Rebuild your box and plug the lines and then see how it turns.

Then hook the cylinder up accordingly to the pressurized hose to retract/extend of the cylinder.

Any mods to the pump?


Pro tip:
fill your cylinder with oil before attaching the hoses.
 
Just rebuilt the entire box with all new seals. The only thing left is the dust cover seal and snap ring that I will pick up tomorrow. The box turns smooth lock to lock with no binding.

@Jeff B no mods to the pump at all. Stock everything with the exception of the hydro assist.

I think my plan is to hook everything up tomorrow and disconnect the ram from the draglink to verify that the the lines are correct. Hopefully the hoses being hooked up wrong created enough back pressure to blow the seal. I did notice that when the Jeep was running, it was very hard to turn the wheel(because the ram and box were fighting each other). At the time I thought it was just air in the lines.

Any other thing I should look out for?
 
you will want to mod the pump. Drill the valve 1/64th at a time until you like the feel. When your pump starts to whine add some aw46 to thicken the oil a bit.
 
I installed the hoses backwards on my cab truck many years ago when I first put the system together. I had the front end on jack stands, and started the truck up. I just touched the steering wheel, and it immediately went full hard right and wouldn't turn left. I quickly cut it off. I swapped the hoses around, and then it worked like it was supposed to. That is my only experience with plumbing hydro assist. I drilled and tapped the box, but didn't know which hose to hook where, so I just guessed figuring I would know if it was correct right away, LOL.
 
drkelly said:
I installed the hoses backwards on my cab truck many years ago when I first put the system together. I had the front end on jack stands, and started the truck up. I just touched the steering wheel, and it immediately went full hard right and wouldn't turn left. I quickly cut it off. I swapped the hoses around, and then it worked like it was supposed to. That is my only experience with plumbing hydro assist. I drilled and tapped the box, but didn't know which hose to hook where, so I just guessed figuring I would know if it was correct right away, LOL.
Click to expand...


Yea, these and the old Bendix power steering ram assist like 60s cars had don't reach through bthe wheel to crank the car if you're not sure it's right. Otherwise you're probably going to the hospital LOL!
 
It blew the stub shaft seal again. I rebuilt the entire box last night with all new seals. Left the pitman arm off and swapped hoses. While I was bleeding the system, the wheels would turn opposite of steering input so I don’t know if I had them correct the first time or if there was air still in the system.

I’m at a loss. This is the 3rd time I have had the box apart and the 3rd time it has blown the input shaft seal. All the other seals are holding just fine.
image.jpg


image.jpg


image.jpg
 
Apparently I'm a dumbass. I ASSumed that the high pressure port on the box was nearest the stub shaft and the low pressure hose was the other one. Apparently I have them backwards, can anyone confirm which port on the saginaw box is the high pressure and the return?
 
YJJPWrangler said:
Apparently I'm a dumbass. I ASSumed that the high pressure port on the box was nearest the stub shaft and the low pressure hose was the other one. Apparently I have them backwards, can anyone confirm which port on the saginaw box is the high pressure and the return?
Click to expand...

with both hoses off the box, look down into both ports. One you should be able to see into the box and the other should look like it’s “blocked”. The one that you can see down into the box is the low pressure/return side.

edit: see below pic
DD97840E-B174-4EB7-8DB8-422EFCAFCDAF.jpeg
 
@adamk thats all I needed to see. That picture confirmed my theory that I had the lines switched, which I can’t for the life of me figure out how it happened. Also your blocked/unblocked port is spot on. The low side port I can see down into the box, the high side port is obscured.

I’ve resealed the box but am running into an issue with my high side hose not sealing to the box. The hose was built by Pirtek in Charlotte and they originally made it for the low side port which is a smaller diameter than the high side port. I found a fitting that allowed me to hook it up but I was t getting a solid seal. I could turn the wheel with the engine off and could hear it weeping and could see fluid pushing up around the fitting. I’m going to have pirtek remove the smaller diameter fitting and replace it with the correct sized one.

This *should* fix the issue of the seals blowing out. The last thing I am questioning is the hoses from the box to the ram. From the picture above, the left port on the ram is connected to the top port on the box for hydro assist and the right port on the ram is connected to the bottom port. When I was bleeding it earlier(before the seal blew) I was getting opposite effects. Turn the wheel left and the ram went right. Could this be affected by the wrong inputs from the high pressure port(ie air bubbles, insufficient pressure)? Even if I do have wrong inputs and the seals hold tomorrow, that’s an easy fix to swap them out.

Hopefully tomorrow I’ll be driving out of the garage and not covered in power steering fluid

:beer::beer:
 
Are your threads into the box not tapped NPT threads? Just wrap more tape around the threads to see if that works to seal it up.
 
@rockcity, they are NPT threads. The issue is that the adapter bushing is too deep and the hose input bottoms out of thread before it makes a seal. It should be a simple change.

@adamk thats how they are right now. I'm assuming that my opposite steering was from the incorrect hoses and pressure issues.
 
I have a trimmed tapp that I use for that port, lets the fitting go a hair deeper.
 
Back
Top