Disco 2 D2 ACE Pipe replacement - whirring/groaning noise

I recently replaced the high pressure pipe from the ACE pump to the valve block after finding a small pinhole leak near the radiator. Since doing this I now have a whirring/groaning noise that changes with the revs and is more noticeable at low speeds, almost like a dull echo. I think there is a pipe touching something somewhere although I cannot find it and have done my best to isolate all the pipes from each other and the body/chassis.
Question is, is this ok to leave like this? If it's not going to cause any problems I can just about put up with the noise.

I think it is the loss of the damper in pipe.

Do you have the remains of the old one?

If so you may be able to modify it to fit into the new hose.

What did you use for the new pipe?

MJI said:

I think it is the loss of the damper in pipe.

Do you have the remains of the old one?

If so you may be able to modify it to fit into the new hose.

What did you use for the new pipe?

Click to expand...

I used a Britpart replacement pipe, this came in two sections. Whereabouts it the damper (a photo would be good)? I am fairly sure that apart from being in two sections it was fairly identical to the old one.

Did you fit a new original pipe there? cos it's supposed to have a spring loaded ball atenuator in it especially to damp that noise

just seen the post above, we were writing at the same time

I have no pictures sorry as I chopped off and used hoses for the last metre.

sierrafery said:

....cos it's supposed to have a spring loaded ball atenuator in it especially to damp that noise....

Click to expand...

Tell me more! We are talking Britpart here

Unfortunately i binned the old one long time ago when i replaced mine cos it would have been good now to cut it along to see what's in it, it's possibe that britpart messed up with that atenuator,

From the ACE system description (RAVE):
"The flexible hose which supplies pressure from the pump to the supply pipe attached to the front cross member is
fitted with an attenuator. The attenuator comprises a bullet shaped valve which is located between two spiral wound
springs held at each end of the flexible hose. This valve operates as a restrictor to damp pressure waves of hydraulic fluid from the pump, reducing noise and strain on components downstream. The attenuator is integral with the supply hose and pipe and cannot be serviced separately."

Do you know what it would look like? I have the old pipe still that would have been original, but cannot see anything like that on it (not that I know what I’m looking for)

I dont know, i presume that it should be inside the flexible part somewhere, cut it along and see then share your findings, maybe if you squeeze it you'll feel where it is

sierrafery said:

I dont know, i presume that it should be inside the flexible part somewhere, cut it along and see then share your findings, maybe if you squeeze it you'll feel where it is

Click to expand...

If found some images online HERE. They don't say what brand they are though, so I still don't know if it is something included with the Britpart one. Without cutting open my pipe I have no idea if its there or not.

those pics are interesting ... though i can't see anything like in the description from RAVE... i'm out of ideas

sierrafery said:

those pics are interesting ... though i can't see anything like in the description from RAVE... i'm out of ideas

Click to expand...

I'm assuming they are showing the attenuator in the parts they've cut open, which makes me think that not all the pipes have them!

I've replaced mine twice now, once with hoses (vehicle got wrote off in RTC) and last year with stainless steel pipe. Both times losing the attenuator and gaining more noise.
I did cut my original pipe open though to have a look. On the flexI pipe from the pump there are 2 metal collars compressed around the hose. These keep the attenuator in position inside the hose.
I've got it somewhere still in my garage. If I find it I'll take a picture.

tom1979 said:

I have the old pipe still that would have been original,

Click to expand...

If it is only a pinhole that caused all this problem, would you not be able to put a drop of weld on the pinhole and solve the problem by refitting it?

These are from the inside of my first original hose. There was no bullet shaped valve inbetween the two pieces though. Each was clamped by the metal collars to hold them in position inside the hose and a gap maintained in the middle. I can't remember which way round they were but the black part has a smaller bore.

I've got exactly the same problem with my V8. I changed all the pipes between the pump and block, flow and return. I've also restored all the original fixings (to which half were missing before) and made sure the pipes aren't touching anywhere as I can't stop the whine - it sounds like Pas on full lock constantly. It was all quiet before I changed them as I had a small leak where the HP rubber hose joins the pipe. I've swapped the pump from my offroader and there was no change. If I run a shorter aux belt so I miss out the ace pump all is quiet. In the end all I can point it at is the quality of the pipes. The pipes along with the Pas pipes that I done at the same time cost £500 so I'm reluctant to buy any more!