Odd problem with bleeding hydro-assist

[mrk5]

I've been fighting with this for a while and can't figure out what's going on. So here's the series of events:

1. Install PSC ram with a used steering box from a friend. Tapped end cap and sector shaft cap. Did not touch the pump or reservoir. Also kept stacked plate cooler in system. Everything worked fine on 100mi trip with trail run.
2. Decide to install hi-flow pump from PSC with remote reservoir. Everything else stays the same. I begin having no success bleeding the system. Thinking maybe it's a pump issue, I switch back to my original pump with the remote reservoir; still no luck. I notice that the end cap on the gear box is moving in and out while turning the wheel. So I hypothesize this may be allowing air to suck in.
3. Purchase new cap from JKW and install in my old box with the tapped sector shaft from my friend's box. Also replace stacked plate cooler with heat sink style cooler after reading that stacked plate cooler is not best option for steering systems. Re-install hi-flow pump. Still cannot get the system to bleed. Notice the new cap will also move in and out so I run a bead of RTV around it. Still no change.

When I say it doesn't bleed out, I mean I'm not even getting past the point of cycling the steering with the motor off. What I've noticed most recently on the past 2 days I've messed with it is that after sitting over night the first couple of cycles of the steering I hear no air bubbles. However, as I continue to cycle air bubbles start emerging and the level in the reservoir rises a little. It's like air is being pushed into the system. It only took 5 complete steering cycles this morning for the air bubbles to appear. As I continued to bleed the rise and fall of the reservoir level was getting closer to the top of the reservoir.

Myself and a friend have thoroughly examined the system for leaks and found none. We even pressurized the reservoir with 40lbs of air which produced a leak on both of the cooler fittings. We tightened those up and they no longer leak. We didn't find any other leaks and tightening those fittings made no difference.

I do have hydroboost and I have bled it out through out this ordeal and haven't had any trouble getting it to bleed out completely.

Just to clarify what I'm doing to bleed the system; I have the tires removed with the front of the truck up on jack stands. All the lines are connected. I have been cycling the steering lock to lock with the motor off. Yesterday when a friend was helping me, we did 40 complete steering cycles at one point in addition to numerous other times through out the day. During that day we also bled the hydroboost of all air by disconnecting the ignition wire and cranking the motor 5-10sec followed by depressing the brake pedal 6 times. We repeated this until no bubbles issued from the return line.

I have tried starting the motor a couple of times and it doesn't take long - <1min - for the pump to start cavitating. It will cavitate with the truck just idling not using the steering or brakes.

I just keep thinking that air is being sucked into the system during "bleeding" but I can't find where it's coming from. I'd think the source of the air would allow fluid to leak out when it's sitting idle, but there are no signs of a leak.

I have checked and I'm getting full stroke on the ram. Although I'd think any air in the system from the ram not stroking completely would only show up once the motor is running.

I'm stumped and frustrated.

 

[mrk5]

Pictures:

 

[Jason4x4]

Do the lines on the remote res only go one 1 way? I see they are all really close together, and I would think that it could potentially be causing an issue?

 

[mrk5]

Not sure what you mean.

There is one -10 line that goes down to the factory reservoir/pump. Next to that is a -6 line that is the return from the steering gear (the blue hose). The upper most is a -6 line that is the hydroboost return line.

A while back, I checked with PSC and the 2 return lines are hooked up in the proper place.

There are more hoses running around because of the hydroboost.

FWIW, the clear line off the reservoir cap is the reservoir vent that I have running into a little catch can.

 

[Jason4x4]

that's what I mean, are the 2 return lines on the correct ports.

 

[mrk5]

Yep. Verified with PSC.

 

[Jason4x4]

why is your belt routed incorrectly?

 

[Jason4x4]

and what did you do with the oe return ports on the pump?

 

[miniwally]

I want to say it's something with the res.? It would be odd but is the -10 hose to the pump rated for suction? Perhaps the hose is sucking in on itself. Maybe even inside where you can't see the outside moving.

Or
What I would do first. Crank the wheels all of the way one direction. Remove the steering line to the ram on the side that should be full of fluid at that time and either fill the ram or make sure it is full. Then turn all of the way the other direction and repeat this process.

Then do the 5,000 turns lock to lock with motor off, turn on motor and just let it idle with no wheel input. Just let it move the oil around for a few minutes then start turning a little each way. Don't go full lock yet.

If that is okay then work your way up to full lock turns. If at any time the pump squeels get the motor off ASAP and just let it sit for a while.

Other wise I have no good input for you.

BTW sorry I have been a little quiet lately. Been sick, house is with in a week of done and the sinus infuktion I have has kicked my butt.

 

[mrk5]

why is your belt routed incorrectly?

It's an aftermarket serp setup from GM Performance. I think it's technically for a '90ish Camaro. I know it's routed different than B_to_C's 90k5. I also found out the hard way that his passenger side bracket assembly is completely different.

and what did you do with the oe return ports on the pump?

There is a jumper hose between them hose clamped on, no leaks.

 

[mrk5]

If I read this right, the only constant factor throughout your troubles would be the remote reservoir...

Yes, I agree; the same thought just occurred to me - one benefit of typing this all out. I was just out disconnecting the remote reservoir from the system and I'm going to inspect the ports - specifically the -10 feed to the pump.

As a side note to all my struggles, when I first installed the reservoir it was leaking around the base of the "can". I pulled it appart and from mill filings in the groove for the o-ring. The filings had nicked up the o-ring and thus it leaked. It's not occured to me maybe there are more problems with the reservoir base. I shall post back if I find anything.

 

[mrk5]

I want to say it's something with the res.? It would be odd but is the -10 hose to the pump rated for suction? Perhaps the hose is sucking in on itself. Maybe even inside where you can't see the outside moving.

Or
What I would do first. Crank the wheels all of the way one direction. Remove the steering line to the ram on the side that should be full of fluid at that time and either fill the ram or make sure it is full. Then turn all of the way the other direction and repeat this process.

Then do the 5,000 turns lock to lock with motor off, turn on motor and just let it idle with no wheel input. Just let it move the oil around for a few minutes then start turning a little each way. Don't go full lock yet.

If that is okay then work your way up to full lock turns. If at any time the pump squeels get the motor off ASAP and just let it sit for a while.

Other wise I have no good input for you.

BTW sorry I have been a little quiet lately. Been sick, house is with in a week of done and the sinus infuktion I have has kicked my butt.

As a matter of coincidence, the -10 hose has been swapped out in the middle of this. I relocated the ressy and was able to use the hose that came with it, before I was using a hose from the local parts store.

I haven't looked to see if it's being sucked shut. Going back to Michael's post and my reply, it does seem like this could be caused by lack of fluid being supplied to the pump. However, I have this problem without the motor running so the pump should be producing much suction; at not enough to suck the hose down.

 

[mrk5]

Well, I'm going to give PSC a call tomorrow. I noticed some odd things with the reservoir.

First the fitting for the outlet to the pump steps down in I.D. The o-ring half of the fitting is 3/8" ID and the -10AN side is 1/2" ID. Seems like the step down in ID results in an aweful small size. Here's a pic:

I also noticed the little holes leading into the outlet port don't quite line up right. Half of them are about half blocked. Not sure how easy it is to see, but here's a pic:

So, I'll give them a call to see if this stuff is unusual or if it is all okay.

 

[mrk5]

You can definitely hear it moving a lot of fluid around.

 

[6.2Blazer]

And nobody thinks the end cap moving in and out is an issue?

 

[mrk5]

FWIW, I did some searching about the end cap here and through Google. I found one thread here in which 4x4 High posted that his end cap moves and doesn't have any problems, but that's the only mention of it I could find. I also called Stephen about it and he had never heard of such an issue one way or the other.

At first I thought sure it was the problem, but the more I think about it I'm not sure. The cap has a recessed area around the perimeter where the o-ring seats. Once the cap is seated in, shouldn't matter if the cap moves in and out because the o-ring will keep it sealed as long as the o-ring is in good condition.

I could be wrong and I'd sure like to hear any opinions.

 

[mrk5]

I tried putting a factory remote reservoir on and I seem to be having the same problem. The longer I cycle the steering, the more air I get from the return for the steering; and we're talking about a lot of bubbles.

Maybe it is the end cap. I certainly don't see anything leaking throughout the system. It's like it would be something allowing air to be drawn in but not allow fluid out.

Haven't heard anything out of PSC yet after sending them a detailed e-mail yesterday AM and leaving a voice mail in the PM.

 

[mrk5]

Okay so the next thing I've done is removed the ram from the system. I stuck the hose ends into p/s jugs submerged in fluid and capped the fittings on the steering gear box. The steering works just fine. I can run the motor no complaints from the pump running the steering back and forth, no sign of air.

So everything works fine with the system complete with the exception of the ram. I have the heat sink cooler, hydroboost, and factory remote reservoir all hooked up with the same plumbing.

What is wrong with the ram or what am I doing wrong with the ram.

 

[miniwally]

See my post above. It's hard to get the air out of the ram sometimes.

OR

The end cap is your issue somehow with the assist hooked up.

other than those I got nothing for you.

 

[mrk5]

My eyes glazed over when you said "5,000 turns lock to lock".

So in other words I need to be more effective with bleeding the ram. Pulling the hoses off and submerging them was one trick I read, so that's why I went ahead and tried disconnecting the ram first. Now the trick is trying to hook them up and loose as little fluid as possible out of the hose ends.