Hi Everyone,

I'm having a bit of a nightmare trying to resolve a noisy ACE pump.

Whilst I've always known/thought it was the pump I replaced the cheaper bits before shelling out £1k on a new pump. So with this in mind I've replaced the two idler pulleys that are located close to the pump (to rule out any noise transference and also at 10 years old they benefited from being changed), I've replaced the reservoir (to rule out the micro filter in there) , I've replaced the main valve block (to eliminate the possibility that the solenoids aren't working correctly and also I saw a cheap new one) and lastly I've changed the actual pump. The system was bled and flushed using the usual process and passed each of the three times it was ran. However it's still screaming like a banshee when it hits 1500rpm and above.

I'm kind of at a loss as to what else it could be, the stethoscope pinpointed the pump. The Land Rover warranty means they want diagnose the fault before swapping the pump, I'm just a little worried that the dealership will try to explain the fault away and blame some other component whist fleecing me in the process (I'm already into this repair for £1600+ so not really keen on spending anymore ).

Any ideas on what else it can be ?

Thought I had better post under this section you socast
I am having the same problem also and I have changed pump, flitters & fluid
Ive spent £1350 so far  2006 RR Sport Supercharged Love this car
2009 BMW 335D GONE
2008 VW R32 GONE
1999 RR SE GONE
1994 RR HSE GONE
2001 VW V5 GONE

I've changed everything bar the roll bars themselves, but it's physically impossible for it to be them. The only possibility I have left is part: RQA500018 this is the bunch of pipes that leads to the front sway bar, reservoir and pump. But at £300 and a partial body lift to replace them I'm somewhat hesitant to pull the trigger.

Are you absolutely sure it's not the alternator? I had a very similiar thought about the ACE pump being noisy and firstly suspected the reservoir was starving the pump with a blocked internal filter so I changed that, plus I changed the high pressure filter in the valve block at the same time. Of course, the noisy high pitch whine remained so the next thing was plan to change the pump.
However, before I got around to changing the pump, the alternator gave up, lots of weird electrical behaviour followed immediately by the red battery on the dash.
I had the alternator replaced and no more noise. Not once did I suspect the alternator, I've never heard one make a noise like this, when I've had failed alternators on other vehicles in the past they've always made a more low pitch grating noise, not a high pitch whine.
I know you've checked with a stethoscope so you're more likely to be confident about what you think is at fault, just saying don't discount the alternator, it had me fooled

I'm certain it's not the alternator as I've replaced it already, along with all idlers that are near-by. The confirmation was when I used remote microphones, the pump is noisier on the inlet than it is on the outlet oddly enough.

Does the ACE fluid look aerated in the reservoir after a good long drive? Even the slightest of leak anywhere in the pipe between the reservoir and the pump, will be enough for the pump to pull in air and make it sound bad.

Nope, fluid is fine. Following my opening post Other than the sway bars it's a completely new system, pipes, valve block, reservoir and pump.

The pump before it was bled up was silent, the second the oil from the reservoir reached the pump it started to whine.

Socast wrote:

I'm certain it's not the alternator as I've replaced it already, along with all idlers that are near-by. The confirmation was when I used remote microphones, the pump is noisier on the inlet than it is on the outlet oddly enough.

I've had remote microphones on the pump it is 100% the pump. I replaced the alternator 2 months ago. When I changed the ace pump I filled the reservoir and started the engine, no whine, the second the oil reached the pump, it started to whine.

If the noise is definitely coming from the pump, then it's either another faulty pump OR there is something restricting flow from the pump causing it to work beyond its design limit OR it is cavitating due to a restriction of fluid feed from the reservoir.
As you have changed the reservoir, you can rule out a blocked microfilter (within the reservoir), have you checked the pipe between the reservoir and the pump for kinks or anything pinching it?
If this pipe looks ok, then you'll need to investigate a restriction between the pump and the valve block. As there is a pressure transducer on the valve block, any restriction from the valve block to the ARB's would like throw a fault up on the dash.

There than the ace bars and part number rqa500014 I have replaced the ENTIRE system with brand new components. Everything is as it should be, the system passes all tests and throws no errors/fault codes. Land rover have said the pump is fine and that's how it's supposed to sound...

My ace pump is brand new too, I will have another listen to the pump tomorrow as I haven't had time since Wednesday then I got the RR back.
I will also see if I can get to the alternator too. 2006 RR Sport Supercharged Love this car
2009 BMW 335D GONE
2008 VW R32 GONE
1999 RR SE GONE
1994 RR HSE GONE
2001 VW V5 GONE

My noise is defo still coming from the ACE pump, it still sounds the same before I have the new pump fitted !!!
and the noise sounds awful my wife took the dogs out in the RR yesterday and when she pulled away all I could hear
was the ACE pump !!!!!!  2006 RR Sport Supercharged Love this car
2009 BMW 335D GONE
2008 VW R32 GONE
1999 RR SE GONE
1994 RR HSE GONE
2001 VW V5 GONE

When you changed the pump and fluid, I'd you fit a new reservoir?

Yep 2 new filters, new fluid, new pump all fitted by www.west4x4co.uk 2006 RR Sport Supercharged Love this car
2009 BMW 335D GONE
2008 VW R32 GONE
1999 RR SE GONE
1994 RR HSE GONE
2001 VW V5 GONE