As title when almost on full left lock a horrid graunching noise and vibration from steering. Does it on right lock occasionally. This is with car moving forwards very slowly. I never rack the wheel over to lock when stationary. Fluid is a good colour and full. It has done this to a lesser degree just a few times over the last year but suddenly it has got worse.
Any suggestions?
I will be taking it into my local garage next week for a check but would like to be forewarned.
Thanks.

 

Dunks, does it do it worse when you quickly turn the wheel? Or does it seem to only do it when the wheel is turned and then held in a certain spot? If it does it when quickly moving the wheel, then I would suspect that you have some crud build up inside of one of the lines. If it is doing it as you hold the wheel in one place, then I would suspect that you have some internal leakage in the steering rack.

Just to ask the silly question, do you have the correct fluid in the power steering pump?

 

Thanks Thermo. Yes it's the correct fluid.
The noise and vibration comes when the wheel is slowly turned and happens just before full lock. Noise stops when full lock is reached or turning is stopped.

 

DUNKS, it is sounding like you either have a restriction in the system or the power steering pump is not developing enough pressure to do what you are after.

I know this goes against what you like to do, but this will be a "once in the life of the car thing". Start the engine and with the car stopped, turn the steering wheel lock to lock. If you feel it hard to turn, then I would be looking at the power steering pump.

The other thing that you can try is disconnecting the line at the steering rack and draining the fluid out. See if you get any fine grit out. From there, you can refill the system and see what you have at that point. It may be that you simply have some junk at a low spot in the system and you are moving it around as you turn the steering wheel, leading to the noises that you hear.

 

Dunks, did a little more looking. Start the engine and then remove the cap off of the overflow bottle. You should have a little bit of fluid moving through the bottle. Does this fluid appear to be aerated? If yes, then this would help confirm a kinked/semi-blocked suction line (ie, inlet line) to the power steering pump. As crazy as this may sound, if you used just a straight power steering fluid, you may want to try an "asian" power steering fluid. Those have an anti-aerating chemical added and it may help with the noise.

The other thing to look for is whether the fluid is cloudy or if it is pretty clear. It should be clear. If it is cloudy, then you have water in the fluid and it will need to be changed.

All the symptoms relating to noise while turning either point to a bad suction hose (blocked or kinked) or the power steering pump is toast. The suction hose is the one running between the overflow bottle and the power steering pump. That is going to be the cheaper piece to replace if you are going to take a stab in the dark as to what is wrong.

 

Thanks again Thermo. Tried the stop to stop whilst stationary. Did it several times. Smooth as silk each way and no effort until just before full left lock then the graunch and vibration which occurs over a very small ark. No sound at all from right lock.
Fluid is clear and no air.
Will see what Mr mechanic say next week.
Thanks for the suggestions will keep you posted.
Peter.

 

Update.
BROKEN NEARSIDE SPRING.

 

Just for interest sake. Had two new Ford springs fitted at local garage. Cost £140.
Estimate from Jaguar main agent £638. But would not do springs until I had paid for a full diagnostic on front suspension. I did not ask cost for this.

I am hoping local council will foot the bill. It was their pothole which broke the spring. Roads in the UK are getting very bad. Councils just cant afford repairs. Would rather pay out compensation. Paid for by their insurance I presume.