Hydraflush/oil change help

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admiral51
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Hydraflush/oil change help

Post by admiral51 »

Hi
the time has come for a hydraflush and filters(all) change on the good ladys xantia (easter used to be work free :) )

have grasped most of the basics on the hydraflush but not sure how the top clip/bracket comes apart on top of the LHM tank is it just push/pull??

as for the oil change ive done a few on other cars but as car is not here till friday cant look to see if sump plug is a hex job or a good old fashion bolt any ideas as to what size hex/spanner it maybe

will be bleeding the brakes so assume its just an 8mm open ended spanner for the bleed nipples :lol: :lol:

thanks in advance

colin
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Post by myglaren »

Mine was a pretty hefty hex key, still lurking in a toolbox.

For the bleed nipples, I'd use an 8mm ring or socket to start them off, easy to round them off with an open-ender.
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Post by CitroJim »

Hi Colin,

The LHM reservoir clip is a just a springy job that clips on and needs a hefty pull outward to unclip it from its lugs.

I drain the LHM reservoir before removing it for a good clean by syphoning out the LHM. warning, LHM tastes nasty but I don't think it's toxic but be careful how you start off the syphon :lol:

Then it is easy to slip off the LHM reservior and expose the filters without strainging the pipes too much. Give the filters a good clean in petrol. Don't use anything else. Give the reservoir a good clean out, minding your hands as it has some sharp edges. You'll be amazed at how much rubbish accumulates in the bottom. Clean the filters again after the hydroflush has spent 1000 miles doing its work.

The sump plugs normally have a 21mm hex (13/16" AF fits well) on the outside except some gearbox plugs which have a strange "D" shaped hole in them. Always renew the copper washers. Annoying drips will be the result if you don't. If you change the gearbox oil, only use 75W/80 oil.

Get a really good quality 8mm ring as Myglaren suggests for the nipples and give them a gentle wire brush and a squirt of Plus-Gas before cracking them open. One of the beauties of LHM is it's not hygroscopic so does not absorb water and thus the nipples don't corrode like conventional braking system ones do so a seized nipple is very rare. Still go carefullly though and be aware the fronts are not that accessible. Be sure to replace the nipple dust caps.

When bleeding the rears bleed at least 250mL per side as the lines are long and it takes quite a lot of fluid to get all the air out. If you take extreme care with clenliness, you can reuse what you bleed out or use a very long bleed tube to dump the bled LHM directly back into the LHM reservior.

With the cost of LHM these days, you don't want to waste any!
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Post by admiral51 »

thanks Myglaren and Jim,

bit of a typo or more to the point DAFT moment i really meant ringspanner :oops: :oops: :oops:

hope that the nipples should be ok as had all the pads changed 6 months ago so fingers crossed :lol: :lol:

i assume that the clips on the pipes could be reused but best to use new jubilee clips or atleast have some on standby :) :)

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Post by CitroJim »

admiral51 wrote: i assume that the clips on the pipes could be reused but best to use new jubilee clips or atleast have some on standby :) :)
No need to disconnect any pipes if you drain the LHM reservoir first Colin. You can tease the reservoir out from under the filter head then without disconnecting anything.

A good tip is to have a clean 4 pint plastic milk carton cut down to about 5" high ready for when you pull out the reservoir to slip in under the filter head to catch the LHM drips. LHM will drip for ever from the filter head and make a real mess as LHM still trickles up the leakage returns.
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Post by Clogzz »

a hefty pull outward to unclip it from its lugs
Changed the LHM 2 weeks ago, and took the tank out to clean.
The springy clip comes out easily by pushing the front end down, then up along the outside of the catch.

Last time the tank came out was over 7 years ago, and done 101,000 km since, with LHM syphonings and refills along the way.
There was some small black debris in the filters, looking like pieces of O-rings from sphere changes.

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Post by myglaren »

The GS ones were dead easy and pretty too.
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Post by admiral51 »

hi superloopy1

got it all done yesterday before the downpour :) :)

the bleed nipples were not as bad as i thought possibly because i had the pads/discs changed last august and the system bled
had to go and buy an 8mm deep socket and ring spanner cos i couldnt find my other ones must be burried in the shed :lol: :lol:

i only had access to one axle stand so did it this way
set to high setting and jack up front n/s to get axle stand under then lower on to stand remove wheel and with engne running and suitable block of wood wedged between seat and brake pedal crack the nipples off and wait for the bubbles to dissapear :)
then repeat the proccess for o/s/f n/s/r o/s/r

i couldnt find a decent bleed pipe so instead i used the fuel filter water drain pipe very handy that was and it was clear

the brakes will only work if they have pressure on at least one of the suspension arms front and back and this method worked fine for me thanks for the advice Jim :D :D

its not as bad as you think superloopy1 i just took a big gulp of here goes and went for it :lol: :lol:

colin
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Post by red_dwarfers »

superloopy1 wrote:
Hydraulic pipes to both brake hoses are stuck tight, been plusgassed overnight and still wont budge with a 11mm flare spanner and as one is now virtually rounded i'm going to have to take them off back to the block!
I had a problem with a rounded hydraulic union with my height corrector, a decent pair of straight edge grip molegrips are your friend here :wink:
superloopy1 wrote:
Nearly forgot, just to round things off i was jacking the rear just 'slight;ly' ahead of the jacking point in order to get axle stands under when the sill decided to fold in two along a 6" section.

Barely noticeable (but i know it's damaged :oops: ).

an all round bad day for me :x :x :x
You're not the only one, I did this back in my early days of Citroen ownership and folded a bit of the sill a touch :oops: :oops:
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Post by lexi »

Best to loosen the bleed nipples with a hex socket with the same amount of sides as the nipple. It is a far better fit and I always start with it after plus gassing. If one of your nipples is past it try a smaller socket hammered on. Only as last resort mind.........although it has worked for me many a time.

The same trick can work with a union with a pipe on it. Rather than scrap a caliper or similar...............cut the pipe to allow you to get the flat sided socket on. You can always get or flare a new connection.
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