Power Steering Hoses

[PMI]

I finally replaced the pressure hoses. The pipe in the first pressure line was rusted along its entire length under the bumper. So was the union nut and fitting between the two pressure lines. The pipe was so rusted I could easily bend it in my hand. Similar to a recent post and pic from Ragtop.

I used lines from a 9-3 model which are slightly different, but seemed to fit about as well as the old ones (getting them in place was not easy). The union nut between the the first and second line was rusted solid, and had to be cut off, etc...



Above, with front bumper and intercooler removed.
Below, detail of rusted line near the oil cooler lines.




Seeing the hoses and pipes out of the car, I wish I had custom ones made. Given the rust, leaking crimp joints, the awkward location, and cost of new lines, it seems that replumbing the whole system can be done for less that the price of a single oem line with parts readily available.

The threads at the ends of the lines are metric, but adapters from the M16 x 1.5 thread to -6AN hose ends are easily available. The lines have about the same inside diameter as a standard power steering hose.

Has anyone had custom hydraulic lines made?

[earthworm]

I wonder if it is worthwhile to pull the entire front plastic simply to inspect and POR-15 the PS hoses and pipes , PMI ??
How long does this take ?
The pipes(sans the rust) do act as an oil cooler.
Copper tubing as a replacement, as it is easily workable ??
And there is much metric over here now, so this should not be a problem now ??
Asian and Euro metric are different to an extent; Occidental is "fine" thread, Oriental is "course"..
But, the standard (ISO ...) is the same..
So, I hope we are using Euro heavy equipment..

The ravages of rust

[PMI]

Originally Posted by earthworm

I wonder if it is worthwhile to pull the entire front plastic simply to inspect and POR-15 the PS hoses and pipes , PMI ??
How long does this take ?

Oil cooler lines, A/C lines, the long plastic outlet pipe from the two-pass intercooler (if you have one of those) all need inspecting at some point. You can do a decent job w/o taking the bumper and intercooler off, from below and with a really good light (flashlight is not really enough)

- Elevate car on ramps
- Remove plastic air shields, crank pulley cover,
- Remove A/C compressor pulley cover on turbo to see oil cooler lines
- (Bumper can stay in place for inspection only)
- Look for oil on the front cross member of the subframe,
- worn through A/C hose heat shield,
- power steering pressure line below the oil cooler,
- union nut between pressure lines below battery,
- oil cooler lines and hoses running back to the oil filter housing
- inspect plastic intercooler outlet pipe for cracks and signs of oil

Maybe 1-1.5 hrs lying on your back if you have to clean a lot of old crud off.

Not sure about Por-15 on the p/s pressure line, there is not much room to work. I think that pipe was beyond POR-15 on my car. Should be ok on the oil cooler lines.

Much easier with a lift, if you can find one.

I am a bit confused about the p/s line. I looked at the un-rusted sections, and they seem very solid. 10-mm (nominal) steel pipe. 10.5-mm actual OD, 8-mm ID. 1.5-mm wall thickness. Heavy galvanized steel, coated with black paint. It really should not rust, but it does.

[ragtopcav]

Originally Posted by earthworm

The pipes(sans the rust) do act as an oil cooler.
Copper tubing as a replacement, as it is easily workable ??

I've been giving this a little thought; what about the cupro-nickel alloy pipework that's out there. Very high pressure seamless pipe, readily bends [not as easily as pure copper] and very corrosion resistant.

The pipes are an utter chore to do, worse it seems on the turbo with the intercooler and oil cooler in the way. And the problem is the quality of the finish on them .

In the past I've painted mine with reasonable success, [I've yet to have one fail]. One other protection option to consider perhaps, body cavity wax, the spray on sort that has a yellowness to it. This inhibits rust and protects the surrounding areas; anyone tried that?

[Turboken]

Hi,
I had the same problem with my 900t and managed to get as set of hoses made at a local hydraulic specalist for a fraction of the cost, but you must use thr original ends from the oil pump as they are specific to cars, and if you get them made from flexible pipe then it saves removing the front bumper.

Also the P/S pipe can be manufactured using the same flexi pipe as the oil hoses but you must use the original rubber flexible pipe at the pump and the rack as they contain a silencer to quieten down the hydraulic noise of the p/s system.

Hope this helps,
Kenny

p-s , There is a longer post regarding this issue on these forums.

[PMI]

Hi Kenny,

I was beginning to think nobody ever used anything by the stock hoses...

Originally Posted by Turboken

Also the P/S pipe can be manufactured using the same flexi pipe as the oil hoses but you must use the original rubber flexible pipe at the pump and the rack as they contain a silencer to quieten down the hydraulic noise of the p/s system.

The NG900 hoses do NOT have that silencer (restricter) just after the pump, or at the rack.

I bought a set of pressure lines from a pre-92 9-3, and those DID have what you described, even though the rest of the system seems the same. Some kind of restrictor near the pump, and a spring loaded check valve inside a banjo-type fitting at the rack. There must be a reason why Saab added this to the later model.

Maybe you could point me to the other thread (?)

I have installed the two long 9-3 pressure hoses and kept the third, original hard line at my rack. No change in sound or performance, as far as I can tell.

Hope this helps,

Yes, Thanks.

[PMI]

Originally Posted by ragtopcav

I've been giving this a little thought; what about the cupro-nickel alloy pipework that's out there. Very high pressure seamless pipe, readily bends [not as easily as pure copper] and very corrosion resistant.

Almost anything would be an improvement, although I wonder if you really need a cooler in the pressure line. How much cooling can you get from 3-4 feet of straight steel pipe w/o any fins, and in a location that does not get a huge amount of airflow? The fluid is in that pipe for less than a second.

The rusted line I took out was 8-mm ID, 10.5 mm OD, so about 50 sq. mm in interior crossection. The volume of that section of pipe 0.05-0.06 liters. The stock pump is rated at about 1.75 gpm. After some conversions, around 0.11 liters/sec. So, the fluid is in the pipe for maybe 1/2 second if the pump is operating at capacity, at half capacity, maybe 1 second.

[ragtopcav]

OK I'll admit hydraulics are way down at the top of my 'know nothing of' list .

We call the loop a cooling loop, is it really for cooling? or is it to soak up thermal expansion? Bit of both?

In all honesty I don't know the answer, I call it a cooling loop because that is what I was told it was for that.

[Saaboheme]

I have been thinking about this too. What if you replace the metal pipe with rubber and place an honest to goodness real McCoy 2 to 4 pass oil cooler (like PermaCool or some-such) in the loop? I know Jegs has a an okay one for like $40.00, but do not know its dimensions, including interior pipe diameter and gpm rating. The only other issue is where to mount it. I have been thinking about horizontally and slightly titled, below the core support, protected from stones and road debris by a wire screen and mesh cage.