Power Steering Fluid Change Guide with Pics

[Welton]

Note this is not a full drain and refresh of fluid but a working 'flush and exchange' to replace most of the fluid in the system. According to the owners manual the PAS fluid capacity is 1.2 ltrs with 0.2 ltrs being the capacity of the header tank.

Remember throughout the whole of this process you must keep all of your tools, hands, and all surfaces spotlessly clean - you cannot afford to get any grit into the system so clean everything starting with the header's screw cap and right down to the pump - I used a whole can of brake cleaner during this process including cleaning up the excess spillage that occurs. The little extraction hose/syringe were constantly being wiped with clean paper towels. You pretty much need to set out a clean station where you work with everything to hand, lots of paper towel, and something to protect the ground underneath as you WILL get lots of spillage.

First of all I attempted to extract the old fluid straight from the header bottle, this proved difficult because not only was it very difficult to 'aim' the extraction hose down the outlet pipe to reach lower down the system but also the hose gets stuck at an unseen bend in the wheel arch cavity below.

Schematic of the system:


It was only possible to extract the header bottle's contents and 'some' of the outlet hose to below, this was only about 0.2ltrs so useless as a 'fluid change' because the real action and fluid circulation happens at the pump unit below.

Time to get the wheel arch liner out, car jacked up and placed on axle stand (UK drivers side) Note the pair of Adjustable Grips (or plumbers pump pliers) on the floor there, these are essential later on, the wing was covered in plastic sheet to protect from fluid spillages:


Next up was to release the top hose by squeezing the sprung hose clip using the adjustable grips, squeeze the tabs of the clip together and 'walk' the clip up the hose and past the 'nipple' connection. Grip the hose with the pliers, it releases quite easily by twisting/lifting it slightly This is when the rest of the fluid in the hose (that you can't get to with the syringe set) will leak out, it's only about 30mls or so.:




Next up is to use the extraction syringe set (Amazon £6.00) and place the hose inside the top connection (remember super-clean it first) and feed down until it hits the bottom of the cream-coloured plastic tank, this is where you will extract about 400mls of fluid. My syringe held 100mls so I just filled it, pulled the hose off the syringe (it will drip a bit) expelled the fluid into a container and reconnected the hose for the next extraction:


The old fluid (supposed to be green):


Once you've emptied the fluid, reconnect the hose including the sprung-clip just to be safe and begin slowly filling the header tank with new fluid it takes time to fill so be careful, the fluid literally gurgles and bubbles down until the level begins to rise in the header...now stop and put the CLEAN lid on.

The fluid I used - Central Hydraulic Fluid CHF 11S as recommended, you will need 2 x 1ltr tins:


Next start the car ready to work the steering fully left/right to get the fluid pushed around the system a good few times, I chose to put the road wheel back on and take the car off the axle stand so it was sitting normally, as recommended by a brilliant member on here with a YouTube name of SiRobb I placed folded black bin bags under the tyres which makes working the steering really light work:


After working the steering the old fluid in the pipework and steering rack will now be mixed into the reservoir and will need extracting out, switch the engine off and repeat the process above. I did this 3 times so estimate 1.8 ltrs of fluid was exchanged with new, sure there will be some old stuff in the system but not much.

Here's the colour of the new fluid after final top up:


And once all complete you can just see that hose connection by looking down from above so you can check it's not leaking:


Go for a short drive and check the level in the header tank, fill to the 'Full' line printed on the side.

So, has it made a difference?

Yes! the fluid was 15 years old, the steering actually feels 'firmer' to me and more planted, like 'newer' I guess. I thought it would feel lighter but no it has a nicer more stable feel to it.

How long did it take to do?

I chose to keep removing/refitting the road wheel because I didn't want to work the steering left/right with only one axle stand (the suspension moves when you work the steering) I should have put both sides of the car on stands which would have saved time but at the same time I thought it better to have the car level.

It took me about 3 hours, mainly faffing about with the extraction tube in the header tank (trying to aim it further down the hose) and then jacking/lowering/ wheel on/off 3 times etc. but it was ok, none of this is difficult so if you allow plenty of time and work methodically it's a satisfying job.

[Thekilt]

Good write up, might have to check mine out soon and see how filthy the fluid is. Ive only had the car since end December so not sure on the history.

How much did the fluid cost?

[Welton]

Thanks, the fluid was £16.00 per litre so £32.00 total plus syringe £6.00 plus brake cleaner fluid for tidying up £6.00.

£44.00 might seem a lot but I think it's well worth the effort, I'm pretty sure if you asked a Garage to do this job then they wouldn't have the time to spend draining/refilling carefully like you can do yourself as above.

[Welton]

Having driven for 2 days now on familiar roads I can report the steering has a marked improvement in feel.

The wheel feels 'weightier' in your hands and is very stable in the straight-ahead position, the steering used to feel too light and imprecise with the old fluid.

Well worth changing the fluid!