LHM filter removal

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isisalar
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LHM filter removal

Post by isisalar » 20 Apr 2013, 12:53

Hi guys. My HDI is desperately in need of a hydraflush and the filters must be really clogged. It will be a couple of weeks until I can do the flush so yesterday, with a few spare moments, I thought I'd give the filters a clean. I have done this job a few times. To remind myself I had a quick look in the BOL and this shows the assembly removed with the pipework connected, my pipework still has the factory clips on and with the limited time, I attempted the removal but gave up on it after a while and it's now on the list for tomorrow. Is it possible to do connected, or should I invest in some jubilee clips and some side cutters.
Also, is there anything other than petrol suitable for cleaning the filters, eg. white spirit.
Just had a thought, does unbolting the tank give the necessary clearance to remove the filter?
I'm thinking that the presence of those factory clips could mean it's on its original LHM, notwithstanding the FSH.
Kind regards
Paul

addo
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Post by addo » 20 Apr 2013, 13:05

Buy a Sealey or similar "Clic Clip" tool. This allows R&R of the original clips.

Xantidote
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Re: LHM filter removal

Post by Xantidote » 20 Apr 2013, 14:55

It may be a bit fiddly, but I've managed to remove the LHM reservoir without first disconnecting any pipes, though I recall some pipe bracket had to be removed. To minimise spillage, I syphoned as much of the LHM out to start with, as you have to tilt the reservoir to get it clear of the filters etc.

There will be some escaping LHM, so cover the gearbox etc with newspapers and rags before you start. Also, have the bottom half of a 4 pint plastic milk container close to hand, which you lower the filter assembly into, so as to minimise spillage and to keep it from picking up any dirt.

isisalar
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Re: LHM filter removal

Post by isisalar » 20 Apr 2013, 16:49

Re the LHM sloshing out, I'm not doing a change so I thought I'd put it on high which would leave me with a less full resevoir.
Re the clips addo they're not the evil spring loaded ones, they're definitely not re usable, I think they're crimped on.
How about the white spirit?
Cheers
Paul

JohnD
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Re: LHM filter removal

Post by JohnD » 20 Apr 2013, 17:06

isisalar wrote: they're definitely not re usable, I think they're crimped on.
l
When I had a Xantia I cut through the clips with a junior hacksaw, then fitted small jubilee clips.

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VertVega
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Re: LHM filter removal

Post by VertVega » 21 Apr 2013, 20:21

When I had Xantia I always re-used the crimped on clips after releasing them.
I used a thin/small flat end screwdriver for releasing. Insert the screw driver end under and lift up.
It pops up open. Once it is loose don't try to wide open and remove it but just move away along side the pipe.
In order to refix I used pliers, squeezing over the "bump" and locking again.
Difficult to explain but it's extremely easy if you get the idea :)

Hell Razor5543
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Re: LHM filter removal

Post by Hell Razor5543 » 21 Apr 2013, 20:36

Hello isisalar. When you started this post you said you were going to do a hydraflush cycle. I would be inclined to wait and clean the filters at the same time. As you will be removing the reservoir (to get it cleaned out of the old LHM) you can move it about to help withdraw the filter assembly. I managed to do this on Gracie both when starting and ending the hydraflush cycle recently. To minimise on spillage I used a small hand pump to get most of the fluids out.

isisalar
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Re: LHM filter removal

Post by isisalar » 22 Apr 2013, 14:24

Hi HellRazor. I was so enamored with the improvement in the behavior of the car now the temperature has got up to a heady 10 degrees+ and the LHM has thinned out I thought I'd at least help it along a bit and give the filters a chance to catch some more dirt before the flush.
In the event the filters were not too bad at all and it hasn't made a lot of difference, still got all the symptoms of needing a flush, so I'm now even more desperate to do so.
I was in the local motor factors this morning to get a litre of LHM and they have a liquid transfer pump for £6, would certainly make the job a lot easier when I come to do it.
To clean the filters, as well as a good swish around in the white spirit, I found that stuffing the filters with kitchen roll and then using contact cleaner aerosol with the tube in place displaced the dirt and transfered it to the paper nicely. I obviously waited for them to warm up a bit before handling.
The LHM is now a lovely golden colour almost identical IIRC to hydraflush. When bleeding the brakes I don't think it will look that different so can anyone say how much I should get out of the brake lines to ensure they are full of flush?
Kind regards
Paul

Hell Razor5543
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Re: LHM filter removal

Post by Hell Razor5543 » 22 Apr 2013, 18:20

Well, the rear brakes will need the most (distance from pump to brakes), but IIRC about 0.5l, front are about half this (but experts will correct me on this if I am wrong). If you are using a clear pipe to bleed the brakes you might see the colour change, even if it is slight. There is a post re spheres, hydraflush, and brake bleeding;

http://www.frenchcarforum.co.uk/forum/v ... 22&t=24595" onclick="window.open(this.href);return false;

isisalar
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Re: LHM filter removal

Post by isisalar » 24 Apr 2013, 20:44

I've managed to do the hydraflush today, nice improvement in general suspension behaviour but still think it needs a centre sphere to be A1. Googling soon.
The LHM I took out looked like used engine oil!
The hydraflush by comparison was like water.
Now on with the brake bleeding.
Cheers
Paul

Hell Razor5543
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Re: LHM filter removal

Post by Hell Razor5543 » 24 Apr 2013, 21:01

Do NOT leave the hydraflush in for more than 3,000 miles. Although it cleans out the pipework, etc., it does not have the same level of lubrication as LHM, and will start to cause problems if left in for too long (hence why they say 5,000KM, which is equal to 3,000 miles). You may not see a rapid change in the performance of the hydraulics, but it does happen. Citroen themselves recommend changing the LHM every 36,000 miles, and running a hydraflush cycle every 108,000 miles.

isisalar
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Re: LHM filter removal

Post by isisalar » 24 Apr 2013, 21:15

I could feel it wasn't quite as slippery as the LHM and I certainly won't be leaving it too long. Can't wait to get the new sphere on now, and see how good hydractive can be.
Cheers
Paul