When my wife left to drive to work with the S-Type, I heard the tyres squeaking like mad (or so I thought) from inside the house. I was wondering already… Only when she came back, she informed me that something is wrong. It took me about 10 seconds to figure out that the power steering fluid (PSF from here onwards) as WAY BELOW minimum! No wonder! And that means that there is a leak.


Hence, out with the air filter box and adjacent ducts as there was visibly somewhere a leak in the vicinity of the power steering pump. The picture above may confuse you: I just used the engine bay of my X-Type, on which I am working as well (big time) to rest the air-duct of the S-Type somewhere...


So now: Removal of the pwr. steer. pump: I sucked out the remaining PSF from the reservoir, removed it, detached the 2 hoses underneath (with a suitable sump-drain-pan located underneath to catch the dripping mess), and removed the bigger hose from the pump as well.


I cleaned that hose with water and detergent, filled it with water, held the lower end closed and pressed a finger from the other hand into the other opening to create hydraulic pressure, but I did not find any leaks, plus the hose looked good anyway.



Next, I removed the pipe from the pump, which goes to the power steering rack. Note, that the nut, which needs to be opened sits very tight and while it is normally a 16mm nut, mine seemed to be a wee bit smaller than that, hence I used a 5/8 inch spanner. The best way to get a grip on that nut is through the openings of the pump-pulley.

Now: Use a 3/8th ratchet and place it directly into the square hole of the tensioner pulley arm: Attach a lever onto the ratchet and remove the tension from the drive-belt by turning anti-clockwise to be able to pull the belt off the pump-pulley (The same applies to the lower of the 3 fixing bolts...).

Next, the 3 long bolts of the pump need to be removed. Note that the upper-most of the 3 is longer than the other 2. Then you can pull of the pump.

I read in other threads that there is nowhere a seal and that that elbow (where the big hose had connected to) is just stuck into the pump, hence the advise was to pull off the elbow and seal it with some liquid gasket... Now that is complete and utter rubbish! Had I tried to pull that elbow off, I would have killed my pump.


My pump looked good, after I cleaned it, but obviously a little leak is not visible as such, hence I devised a little trick to test the pump for leaks: I went and bought a bolt to block the opening for the pipe with. It was a M16 bolt, pitch 1.5 (I just presented my pump at the local nut and bolt place and asked for a bolt). I used plumber's tape around that bold to make it seal perfectly.

Then I created a "chain" of hoses, getting smaller and smaller, connecting them with hose-clamps and ding hot-glue (but ensure you are not accidentally blocking the inside of the hoses with hot glue!). The big end of the hose goes over the elbow of the pump, he small end over the "air gun" of an air compressor.


This done, the pump gets submerged in a bucket of water, pump air into the pump and watch for leaks. I did not have any leaks.


The best guess from here: Either the hose-clamp that was on the elbow of the pump in the car was no longer good enough (hence, I replaced it), or - kind of more likely: The is a rubber seal indeed! Rubber seals tend to leak after all those years. The seal, I am referring to, has an odd shape, is small and black and is located on the pipe, which I pulled out of the pump (going into the steering rack). A leak of that seal would also correspondent with the location of the PSF-leak. Hence, I replaced it. Not with the OE seal, but I used an off-the-shelf FKM, ID 7.8, CS 1.9 seal, green.


Here the green FKM seal is attached already...


Next I assembled everything back together again and I hope for the best now.

PS: And as seen on the picture above: With most of the PSF fluid removed already anyway and with the PSF-reservoir removed, I did a PSF complete change of a different kind:
Note the clear pipe secured with a hose-clamp in the smaller of the 2 hoses, which go onto the reservoir, under the pulley now: This goes to the waste-bin under the car.
Note the garden-hose going into the bigger hose on top: This is the "hose assembly", which I created before and I apply air-pressure from the other end while I hold the
big hose and the garden-hose close together with the other hand: That way I shoot out all the old PFS. Then, after complete re-assembly I fill in new PSF. It's about 0.8L,
which are required. I used Castrol PSF. However, ATF (Automatic transmission fluid) Dexron III might just do the trick.
The "normal way" of doing a PSF change - which I showed here on my X308) goes like that:
https://www.jaguarforums.com/forum/x...change-265754/

 

Power steering fluid is pretty caustic. Old hoses equals pinhole or leak at clamp as you suggest