Faq: Subaru Power Steering Issues

[bigBADbenny]

Faq: Subaru Power Steering Issues

Before replacing or rebuilding the pump, there’s a few things that are easy to do depending on the symptoms.

Including, in no particular order:

Check both accessory belts for wear and or cracked ribs and replace them.
A snapped accessory belt can lunch your engine, when the loose end potentially wraps around the crank pulley suddenly locking it, jumping the timing belt.

Rule of thumb accessory belt tightness is being just able to turn the belt 90’ on its axis at the longest run between pulleys. If you have a tension gauge, the spec is in your FSM workshop manual.

Use the correct procedure to undo and tighten the tensioners: eg undo the lock nut on the pulley *before* adjusting tension and retighten after.
You may need to re-tension the belts a few weeks later.

Saying it again:

Belts, undo the idler pulley bolt before loosening or tightening the tensioner or you’ll break the bracket.

Ditto for the PS belt but iirc you’re adjusting the pump angle: undo the pivot bolt at front, adjust tension with the top bolt, then retighten pivot bolt to lock it off.

Rule of thumb for correct accessory belt tension is being able to turn the belt no more than 90’ across its longest run between pullies.

Replace the low pressure return o-ring, a few bucks from the Subaru parts counter or online.

The OEM spring clamps loose tension with time and use.
Use quality Oetiker or Norma screw clamps on the low pressure hose, both ends.
These clamp types have pressed teeth for the worm, making for secure tension under higher clamping loads.

If the low pressure hose is bulging, replace it with OEM or appropriate aftermarket hose.

Check and clean the strainer in the power steering fluid reservoir, many miss this step and look for faults elsewhere.
This issue causes air bubbles aka aeration in the power steering fluid and is a must to check especially when replacing the power steering fluid.
Whilst the strainer is in the power steering fluid tank in a gen4 Liberty, in other models it’s located elsewhere eg in the pump itself.


Quote from CorgiWerks, SME: “A blocked or restricted strainer in the fluid reservior can aso cause "drop-outs" in the power steering, especially in the Gen4 Turbos

The fluid reservoir in the Gen4 Libertys is at or below power steering pump entry level and the inlet hose needs to go "up-and-over" to get to the PS Pump inlet.

It’s important to ensure that all air is removed from the inlet hose during bleeding the system.

An old suction fitting o-ring or an old, hard and brittle suction home will not seal at the pump properly and air will be sucked in.”

If the power steering fluid is dark and cloudy, not clear cherry red, drop the fluid and bleed the system properly, lock to lock gently on stands, figure 8’s in car park.

To track down hard to find power steering fluid leaks, clean the area thoroughly and use a UV dye and torch kit via eg eBay, to trace the leak source before the affected area becomes inundated with fluid.

If the power steering pump assy is leaking at the joins or shaft, you’ll need a rebuild.

The power steering pump rebuild kits are diy capable, but you may require specialised tools.

The benefit of getting an expert to do the job is generally that all tolerances will be checked according to manufacturers specifications, assuring a long service life.
The job will probably be more time and cost efficient as well.

If you’re still experiencing power steering issues, or the actual pump itself is leaking, contact @CorgiWerx on FB (Sydney, NSW) for affordable rebuilds.
Otherwise, consult your local power steering specialist.

Here’s a link to your cars FSM workshop manual and parts translation and sourcing FAQ.
All Subaru models and markets are available in the various links:

viewtopic.php?f=6&t=34980

[BillyCorgi]

A blocked or restricted stariner in the fluid reservior can aso cause "drop-outs" in the power steering, especially in the Gen4 Turbos

The fluid reservior in the Gen4 Libertys is at or below PS Pump entry level and the inlet hose needs to go "up-and-over" to get to the PS Pump inlet.
It is important to ensure that all air is removed from th inlet hose during bleeding the system.
An old suction fitting o-ring or an old, hard and brittle suction home will not seal at the pump properly and air will be sucked in.

[bigBADbenny]

Thanks!
I’ll add the info with your reference of course

[bigBADbenny]

To add to the faq:

If the power steering pump assy is leaking at the joins or shaft, you’ll need a rebuild.

The power steering pump rebuild kits are diy capable, but you may require specialised tools.

The benefit of getting an expert to do the job is generally that all tolerances will be checked according to manufacturers specifications, assuring a long service life.

[nvmylh]

Hey Corgi do you know if that strainer is the same for GD WRX's? Can it be replaced or do you remove the whole reservior and clean it out?

A guy at work told me his steering intermittantly goes from normal to really heavy. It sounds ok to me, I drove it and felt it for myself, pretty strange.

Fair chance it could also be old orings too

[bigBADbenny]

I did a quick google and some models eg 92-00 have the strainer basket in the pump, best lookup the GD assy in the FSM.
https://www.ebay.co.uk/itm/Power-Steeri ... 3552111257

[BillyCorgi]

The units like the early WRX with the aluminium top-tank reservior have their filter strainer on the fluid return line, that is it will be under pressure. If the filter clogs up, the fluid will overflow (bypass) the strainer.
This does not starve the pump of fluid.

The Gen4 Liberty, with the reservior mounted on the inner guard, has the filter strainer on the suction side.
In this case when the filter strainer clogs up the pump is starved of fluid.
The pump will try to suck in air through the old inlet o-ring or the clamped joint between the inlet hose and inlet barb fitting.
If it cannot suck in air, then the fluid flow may stop and cause power steering "drop-outs".

The filter strainer shown on Benny's e-bay link is not the fluid filter strainer, it is a "top-up" strainer which only effects fresh fluid being added.
The fileter strainer in that model pump (as described above) is on the return line tube spigot (Trying to find a picture)

Cheers!

[bigBADbenny]

Appreciate having an SME proof reading my BS!

Lots more to come including a huge chapter on inlet pressure testing

[jp928]

Cant find a pic of the strainer - its in the reservoir ? Have the classic seeping out of the reservoir, foaming. Have a new hose and Oring ready to go in....hoping that will fix it. Is the system sensitive to type of fluid - have a new container of type F handy..? Party no for reservoir?
thanks
jp 08 gtb 6mt

[BillyCorgi]

Cant find a pic of the strainer - its in the reservoir ? Have the classic seeping out of the reservoir, foaming. Have a new hose and Oring ready to go in....hoping that will fix it. Is the system sensitive to type of fluid - have a new container of type F handy..?
thanks
jp 08 gtb 6mt

A GEN4 Liberty PS Fluid reservoir has the filter/strainer between the upper and lower halves of the reservoir.
The seam between the upper and lower halves is visible.
The strainer is ultra sonically welded in place.

[jp928]

So is it a new reservoir, or can the strainer be cleaned after removal, blowing back through it? sensitive to ATF type - have some new type F handy? Part no for reservoir?
thanks
jp 08 gtb 6mt

[jp928]

Well....I got it done - new hose and Oring. Despite emptying most of the reservoir first it still got messy . Getting hose out was an issue by itself. The reservoir had some visible dirty areas, so I filled it with petrol and sloshed it around and drained it, blew compressed air through it every way I could. Getting the new hose routed properly was another exercise I could have done without. Filled it, jacked the front up started engine, checked the reservoir was fullish, spun the wheel back and forth. There were some odd oscillation briefly, removed some fluid, but after standing overnight all seems to be working fine, no noises any more.
jp 08 gtb 6mt wagon