pass pipes again lhm or lhs fluid???

[jimmy8467]

ok a while back i said i had a small pin hole in my pass pipe, i now have fitted a new pass pipe on a citroen c5 2004 2l hdi 110, and now have heavy steering, iv toped the LHM? fluid up to the mark on the resivour and turned the steering 20 times plus to get the air out but have still got a heavy sortish steering, and the pump has a slight hum. the steering was not heavy before this and only fitted pass pipes, the only thing i can think of is should it be LDS fluid in the resivour as when it was leaking there was green fluid all over the road and i thought lds fluid was orange???? i have only had the car 2 weeks and there is only one resivour or could the last owner been a cheap skate to put lhm fluid in instead of lds... but it ran ok before i changed the pipes on lhm fluid, or can lhs fluid also be green?? any thoughs would be appreciated thanx jimmy

[Mandrake]

A C5 should definitely have LDS not LHM, and LDS is orange to distinguish it from LHM which is green... so if its green somebody has put the wrong stuff in...

They are similar enough in properties though that I wouldn't have thought it would make any obvious difference in the functioning of the system, although you'd obviously want to flush it out and put the right stuff in.

Is there any possibility that there is a restriction to the inside diameter of the new pipe such as something lodged inside the pipe ? If the flow is reduced by a restriction heavy steering is often a result.

I'm not familiar enough with the C5 to know the proper procedure to bleed the system of air, hopefully a C5 owner will be along soon with advice on how to do that just in case it is a bit of air in the system.

[citronut]

i have not had much if any experience with C5 steering but thought it was a completely system to the suspension, so i pretty sure there is more than one reservoir,
i also have no experience of LDS but im sure C5's suspension use's LDS not LHM

[Mandrake]

Good point malcolm, I forgot the C5 had separate power steering and suspension pumps and circuits. My comments relate only to the suspension circuit, I'm not sure what fluid is used in the steering...

[jimmy8467]

thanx for the speedy reply, been checking and i would agree with you LDS. just fitted the pipes and checked to see if they were clear before i fitted them. resivour was practically empty but the resivour shares the same as the suspention, with the suspention chamber being lower than the power steering, so the resivour now is full of LHM, hope someone out there can give me a definate answer, thanx mandrake

[myglaren]

If the fluid level fell too low and emptied the reservoir the pump may need priming.

The method is to replace the filler cap with on similar to that on a self-bleed brake system (which will work if you have access to one) and with a pump (bike pump is adequate) pressurise the reservoir to start the fluid flowing.

IIRC it only needs about 0.5 Bar.
The reservoir is definitely shared and the fluid is definitely LDS.

[jimmy8467]

been on to citroen and you are right it is LDS fluid, how do i go about flushing the system as its pure LHM fluid thats in, and will it damage the pump or is i ok for a day or 2, must of been put in before i got the car as when the old pipes start leaking the fluid was green, so just filled the rsivour up with LHM fluid as advised by a old mate who was brought up on citroens, but times do change, i now know that LDS fluid is orange and what should be in, thanx everyone for the feedback on this and is much appreciated thanx again jimmy

[411514]

I believe it is quite difficult to completely flush the entire system (without a lexia) although I'd imagine it could be done in the same way as a pressure bleed kit does the brakes, or maybe by open the feed each sphere and providing 12v to the suspension pump.
Assuming the LHM you put in only filled the reservoir it might not have actually entered the pipe work of the system so maybe you could get away with just removing, draining and cleaning the reservoir. Sam

[citronut]

I believe it is quite difficult to completely flush the entire system (without a lexia) although I'd imagine it could be done in the same way as a pressure bleed kit does the brakes, or maybe by open the feed each sphere and providing 12v to the suspension pump.
Assuming the LHM you put in only filled the reservoir it might not have actually entered the pipe work of the system so maybe you could get away with just removing, draining and cleaning the reservoir. Sam

i would say there is LHM through the system as Jimmy says green fluid came out of the burst pipe, before he filled the reservoir

[RichardW]

Although there are dire warnings about not using LHM, the front strut return hoses are the same ones used on Xantias and BXs - so the rubber is compatible at least. I understood the fluid was just a bit tighter spec so that they could get away with a sealed system with 5 year intervention. Given the price of LDS I probably wouldn't worry too much about it....

[Mandrake]

LHM and LDS are compatible from a seal perspective as far as I know. LHM was a mineral oil not unlike very thin engine oil with a few additives (anti-froth etc) with LHM plus being semi-synthetic, and LDS being fully synthetic. So it's not the catastrophic instant death to the seals scenario that filling it up with DOT4 brake fluid would be for example.

That said I'm not sure that its wise to leave it in long term, although the seals shouldn't be destroyed we don't know how it will affect the functioning of the system and whether the LHM will deteriorate at an accelerated rate with use compared to LDS etc...there must be some reason they went to the trouble of developing LDS and my guess is its a longer lasting oil so they can increase the maintenance interval... so my advice would be don't panic, but change it for the right stuff sometime soon.