brewster240

posting this for a friend off the drifting forums, having problems with his tow rig

[quote author=Stewart Leask link=topic=29032.msg598847#msg598847 date=1258276439]
posting this in hopes one of you can maybe help me figure this out. if i can't fix this i'll miss irwindale :\

Ok I'm sorry this is going to seem like a novel, I usually search these forums until I eventually figure out my problem but this one has me stumped big time.

about 6-8 months ago my hydraulic brake booster went out, I figured this to be caused by a neglected powersteering leak so I replaced the booster and monitered my powersteering fluid really well afterwards (it gets real hard to find the leaking line when its all sort of covered).

3 days ago my water pump goes out, right before I'm about to make a tow out to california, GREAT. So I decide I'm going to fix and replace all that I can...do the typical fuel filter/oil change, change the water pump, changed the thermostats while I was in there, hot-soaped the surge tank cap, and then figured while I was down there I'd get the powersteering lines fixed, do something nice for the truck for once. I took the lines to a local shop called Hose Fast and had new rubber line crimped to the existing hardlines on all 3 powersteering related lines and replaced all 5 o-rings. detailed the engine bay really nicely so that I could detect leaks and got everything done and installed and put in fluids.

I went to start the truck and immediately I notice that I have no steering (i kind of suspected this, figured pump had to fill the system up and immediately went low) so I shut the truck off within about 10-15 seconds and went to refill. The pump hadn't gone down hardly any. So once again I decided I'll do something nice for the truck and bleed the system via the DIY hydro-flush thread until my fluid is clear. This took awhile to work, my steering was real tight and really tough for first few rotations then got easier and easier. Took us about 2 qt's of powersteering fluid but we finally got it feeling soft and my brake pressure was back up from 500psi max to 1300psi max. We decided to go for a test drive and the first time I hit the brakes the problem arose again, my steering and brakes were gone. I turned around and went home and figured the pump had finally bit the bullet so we picked one up at autozone. Swapped the pulley onto new pump and reinstalled everything again with no luck. I figured maybe there's an off chance the lines had a clog maybe the line shop didn't clean them or there was a mishap so i blew compressed air through each one, they all flowed perfectly. Put the system back together after doing that and still nothing.

SYMPTOMS:
-at idle in my driveway if i press the brakes or try and turn the steering wheel my powersteering pump howls very very loudly as if it has no fluid
-my powersteering fluid is foaming within less than 30 seconds of starting the truck
-my brake pressure is maxing out at 500psi (usual is 1300psi)via the reading off my Brake Smart and my powersteering pump howls when i'm testing brake pressure
-if the truck is idling and i press the brakes my steering wheel kicks to the right for whatever reason

I have no idea what to do, I'm at a complete loss. Having now replaced my powersteering pump, my high pressure lines, and my hydraulic brake booster within the last 8 months I don't know what could have failed. There's NO fluid seeping from the hydraulic booster and last time that failed my brake pressure maxed out at like 200psi, wouldn't even stop the truck. YES all the lines are hooked up correctly and are all on very tight.

Can a steering box create this issue? Is this something really small that I'm just overlooking?


PLEASE PLEASE PLEASE help!! I have an event I must tow my car to and I've got to be gone Wednesday morning or I'll end up missing it. Thank you in advance!
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Atomic

iTrader: (42)

Try taking the power steering cooler out of the loop.

SincalT/A

iTrader: (16)

do you have a steering box or rack?
I know the racks have problems with the valving inside mainly them getting stuck open or closed.

TrickyTransAm

Things to check

1. Make sure you have the Pressure Lines going into the Hydroboost unit correctly.

2. Make sure you don't have the lines pinched off.

3. I hope the hoses/crimps you put on are rated for the pump pressure, otherwise your going to have one nice catastrophic fire.

4. With the truck shut off, raise the front end up. Cycle the steering all the way to the left, all the way to the right about 10 times. This will force fluid through the gear and help to De-aerate the system.
Pump the brakes about 20 times without the engine running (Allow the pedal to come up as much as possible)
You'll see the fluid in the reservoir bubble and it's purging the trapped air.

5. When you turn the wheel, and the pump makes noise, it sounds like the pump is working fine. It's just got a LOT of air in the system. When you pump the brakes, your forcing more air back into the pump, which aerates...and sounds loud. If you took the cap off, you'd see the fluid get white foamy.
Simply Put - Your taking a large solid bubble, and putting it through a fan blade - which makes billions of small bubbles as it chops it up... Which makes the white foam you see.

If you have access to a large rubber stopper, use a hand vacuum pump and put it on the reservoir top, suck the air out, and let it set on there for about 10 minutes. Observe if you see a major drop. If you do, one of your hoses or connections are leaking. This will help to "Pull" the air out.

Hydroboost systems take double the amount of time to de-aerate because it's the highest point in the system. Air floats up, and gets trapped in the MANY channels of the hydroboost unit.

Re-check all your connections - Don't overtighten the nuts. Otherwise you'll cut the o-rings.

Because all you disturbed were the hoses originally...it makes me wonder about the hoses the most.
Unless you trust the crimp shop with your life, I'd strongly suggest getting a set of hoses that are correct for that truck. (Seriously)
The pump is a VERY durable unit, and not likely to fail.