TD5 Power Steering Failure

[rdavies]

Hi, I have an intermittent problem with the PAS on my Disco TD5 where it loses power assistance, only at very low speed, particularly when turning into a car park spot, or turning the steering wheel when the vehicle is stationary. It appears more prevalent when turning the wheel to the left. If I rev the engine up a bit it seems to get better, so I am wondering if the PAS pump is failing at lower rev? There are no visible fluid leaks, the fluid level in the PAS reservoir hasn’t changed (still full) and the fan belt is in good condition.

Has anyone had similar experiences? I am wondering what it is most likely to be, the pump or steering box (perhaps valve rotor failure).

Regards

Richard

[Quiggers]

I have this rather odd fault which appears only very occasionally.

In dry conditions, I loose power assistance for no apparent reason and the battery warning light comes on - happens maybe every few months or so and may happen several times. This also used to happen when I'd press the brake pedal, but doesn't any more.

But, this intermittent fault became very obvious when I was driving thru flood waters last week. Water is getting into or onto something and, no power, but as soon as it dries (in seconds) the dash light goes out and everything's back to normal. Weird...

One day I'll have a look, but it's one of those 'out of sight out of mind' concerns. Fluids are right and the belt is okay... it's a Land Rover... probably built by an Italian factory... did I mention the left rear door lock, it's childproof, the kids can't get in!


Cheers, GQ

[PhilipA]

I reckon Quiggers that its simply your belt slipping. The alternator is on the same only? belt

Could be the same with Richard.
Why not try a new belt and perhaps tensioner .
Richard could also be a seizing steering column UJ , if the D11 has the same system as a D1, range Rover. In this case a bit of WD40 in the UJs could fix temporarily .
Regards Philip A

[rdavies]

Thats an interesting problem GQ.

Thanks for the advise Philip, I will give it a go.

Regards

Richard

[Quiggers]

Thanks Phillip,

If only this little prob was a belt, it's not, annoyingly. At least I don't think so, given: whenthis occasionally happens there is no screeeching of belt against pulley, ie if the pas stops the belt would screech around the pulley being driven from the crank department, but thanks for the idea....I'll have another look. However, there is some weird stuff under my bonnet. (I wish they'd have asked me to design the engine bay, wouldn't be the pig it is; had a look under the bonnet of an LC GTR-XU1 a while ago, how beautifully simple).

Cheers, GQ

[PhilipA]

Well the water thing certainly sounds like the crank pulley is slipping when wet affecting both the alternator and PAS. I agree that even Multi channel belts seem to scream but there is always the exception.
I cannot think what else it would be.
Regard sPhilip A

[Quiggers]

Hey Phil,

stuck those hose in there for minutes today, not a drama, amazing eh?

but i stuck a probe from the multimeter up the fusebox where the 30amp meets the world and there is a voltage drop, but from where????


i figure i have a bad earth (or two or three) somewhere adjacent but irrelevant to the initial issue.

so after a spray of degreaser i found a few (several) wires hanging on by threads.

poor quality connections......

nothing more than the eternal 12v earth prob


cheers, GQ

[rick130]

going back to Richards original problem, I've had a similar thing happen when changing from Caltex Cold Climate/PAS 14315 power steering fluid (the original factory fill, it's a <span style="color:green">green</span> coloured fluid, and the only stuff to use in the ACE system, apparently) to conventional Dex III ATF.
I then went to Castrol Transmax Z (a PAO/ester synthetic ATF, which should be better at handling higher operating temps) and it still happens occaisonally, although with far less frequency than conventional ATF. (and FWIW, Transmax Z is also <span style="color:green">green</span>)

Our Patrol has also always done this at parking speeds/idle (conventional ATF)
I'm putting it down to the (heavily additised) PAS 14315 having a much high viscosity index and lower viscosity at ambient temps compared to ATF, being able to be pumped better at low pump revs.

Any other thoughts ?

[rdavies]

I hope that bad earth solves your problem.

As for mine, I lubricated the steering UJs, checked the belt (it is not slipping), no fluid leaks. Problem still occurring, it hasn't got any worse, intermittent but when it occurs engine is at idle. As soon as I increase the revs it is fine. Perhaps the pump is not pressurising fluid when at lower revs.

Regards

Richard

[rdavies]

<div class='quotetop'>QUOTE</div><div class='quotemain'>going back to Richards original problem, I've had a similar thing happen when changing from Caltex Cold Climate/PAS 14315 power steering fluid (the original factory fill, it's a green coloured fluid, and the only stuff to use in the ACE system, apparently) to conventional Dex III ATF.
I then went to Castrol Transmax Z (a PAO/ester synthetic ATF, which should be better at handling higher operating temps) and it still happens occaisonally, although with far less frequency than conventional ATF. (and FWIW, Transmax Z is also green)
[/b][/quote]

Interesting you mention that, its only started happening since my last service, the PAS fluid was replaced. Makes sense and definitely worth looking at.

Regards

Richard