Flat Accumulator?

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steelcityuk
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Flat Accumulator?

Post by steelcityuk » Wed Apr 23, 2014 9:13 am

Hi all, let me run this past you and see what you think.

After arriving home last week I noticed the XM was making a strange noise and was leaking LHM. I put her on the ramps and checked her over. The LHM appeared to be leaking from the regulator return pipe, the rubber joining pipe had split which accounted for the leaking but the 'knocking' noise? I thought it had to be a blocked passageway or some such issue with the regulator. I've not had a good chunk of time to spend on it but did remove, strip and rebuild the FDV and the regulator. Why the FDV? Well I happened across a thread written by Aerodynamica about his hissing FDV and I'm fed up with mine sounding like something from Willy Wonkas Chocolate Factory. Anyhow tonight I got them fitted back to the car, I've run the LHM throught a filter, cleaned out the LHM tank and filters, etc. It's still leaking from the regulator return and 'knocking'. I thought maybe the return pipe was restricted so I fitted a 'full bore' pipe to the return spigot and run it into a clean plastic bottle, as soon as the regulator bypass (?) bolt is tightened there's a large volume of LHM delivered into the plastic bottle (no leaking from the plastic return housing so that seems to indicate that there's more pressure than the seal on the plastic return housing seal can contain when connected to the usual return piping) BUT the knocking noise returns and it sounds like the rapid cycling of the cut off valve. It was getting dark by this time so I thought I'd call it a night. My suspicion is that the accumulator sphere membrane has split so the pump is trying the pump against what is effectively a dead end but if that's the case what's the difference between a burst sphere and a working sphere that is filled with pressurized LHM? The suspension raises fine by the way.

Does this sound like a feasible scenario? I know it's an easy theory to test but I wanted to know what others thought and if anyone else had had something similar?

Steve.
XM 2.1 SED Hatch-Sublime
Scenic 2 1.9 dCi 130
Scenic 2 1.5 dCi 105 engine rebuild
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citronut
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Re: Flat Accumulator?

Post by citronut » Wed Apr 23, 2014 8:58 pm

i dont know why but i have seen and heard of a dead accumulator sphere causing the blow by return pipe to pop off,

could you problem be due to some fragments of pipe seal getting into the regulator somewhere,

i used to work for H G Havaux Whatlington garage on the A21 near Hastings, we were citroen service agents,

the boss's son employed a freshly fully qualified F*O*R*D mechanic as the garage he trained at did not waht to take on another qualified mechanic at the time,

the first job he was set upon was to fit a clutch to a GS, he was told if he need any help to just ask,

he got it all apart and back together again,

on starting it up the accumulator sphere spit wide open with a loud bang,

the boss's son fitted a second hand sphere which did the same thing,

so he swapped the regulator which sorted the problem,

on dismantling the original regulator he found small bits of pipe seal inside


regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)

steelcityuk
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Re: Flat Accumulator?

Post by steelcityuk » Fri Apr 25, 2014 11:58 am

Thanks for the advice Malcolm.

On stripping the regulator I didn't find any 'foreign' matter inside it which I thought there would be. The noise from a bursting sphere must be incredible.

Anyhow I changed the accumulator sphere and the problem has now cleared up. The faulty sphere was one of the 3 dimples type too. The car rides a little better, the steering a little lighter, the FDV hisses very little. However I'm still not happy with the tick time but until I can get around to fabricating a pressure gauge I think I should see how she goes, off course the replacement sphere could be low on nitrogen for all I know. The little stubby rubber to nylon joining piece has split too so I'm using a 'full bore' piece of piping to return LHM to the tank until I can source a replacement.

I guess a sphere tester would be a good idea too.

Regards.

Steve.
XM 2.1 SED Hatch-Sublime
Scenic 2 1.9 dCi 130
Scenic 2 1.5 dCi 105 engine rebuild
<Gone>
Prius T Spirit-Gadgets Galore
MB A170CDI
XM 2.0TCT Exclusive LPG-V Thirsty
XM 2.5VSX Estate
XM 2.1VSX Hatch
C5 HDi110 Exclusive
Xantia HDi Exclusive
405GTX TD

citronut
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Re: Flat Accumulator?

Post by citronut » Fri Apr 25, 2014 1:25 pm

have you tried the bash the ball bearing trick yet, the one behind the regulator bleed valve,

also if the old sphere dumped all its gas into the system it would pay to let the engine idle for a good couple of minutes with the bleed valve open, then hold the revs up at around 2.500K whilst shutting the bleed valve,

this is what citroen say to do after the hydraulic system has been opened

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)

steelcityuk
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Posts: 7
Joined: Thu Apr 17, 2014 12:04 am

Re: Flat Accumulator?

Post by steelcityuk » Tue Apr 29, 2014 2:17 pm

Thanks again for the info Malcolm.

I reseated the bearing when I rebuilt the engine and such a couple of years ago but I guess it would be worth doing again? I'll have to dig out a brass bolt.

To be honest I haven't had a lot of spare time, we've just sold the house and I'm part way through rebuilding a 1.5 dCi engine and the concentric slave cylinder went on the 1.9 dCi I was using as my main car. I hope to get another hour or so on it soon.

Image

Thanks.

Steve.
XM 2.1 SED Hatch-Sublime
Scenic 2 1.9 dCi 130
Scenic 2 1.5 dCi 105 engine rebuild
<Gone>
Prius T Spirit-Gadgets Galore
MB A170CDI
XM 2.0TCT Exclusive LPG-V Thirsty
XM 2.5VSX Estate
XM 2.1VSX Hatch
C5 HDi110 Exclusive
Xantia HDi Exclusive
405GTX TD

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mat_fenwick
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Re: Flat Accumulator?

Post by mat_fenwick » Tue Apr 29, 2014 4:51 pm

steelcityuk wrote:I'll have to dig out a brass bolt.
I use the copper tip from a MIG welder - the threaded end seats on the ball nicely.
Image

1993 1.9 TZD Turbo Estate
1996 3.9 V8 Discovery
1993 VW LT35 campervan
1985 Hyundai Stellar V8
2016 Hyundai iLoad

citronut
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Re: Flat Accumulator?

Post by citronut » Tue Apr 29, 2014 6:12 pm

i dont think you are meant to do the bash the ball bearing trick tooooooo many times as you can cause it to go out of shape,

and we dont want wonky balls do we :twisted: :roll: :o #-o :lol: :wink:

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)

steelcityuk
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Posts: 7
Joined: Thu Apr 17, 2014 12:04 am

Re: Flat Accumulator?

Post by steelcityuk » Tue Apr 29, 2014 11:41 pm

That sounds fair enough Malcolm.

Thanks for the tip (!) Mat.

I'd like to ask about the O ring that seals the plastic LHM return housing, on the XM workshop manual it seems to show the seal fitting inside the cast body whereas every one I've ever seen has a seal on the outside of the plastic housing. What have others found?

Thanks.

Steve.
XM 2.1 SED Hatch-Sublime
Scenic 2 1.9 dCi 130
Scenic 2 1.5 dCi 105 engine rebuild
<Gone>
Prius T Spirit-Gadgets Galore
MB A170CDI
XM 2.0TCT Exclusive LPG-V Thirsty
XM 2.5VSX Estate
XM 2.1VSX Hatch
C5 HDi110 Exclusive
Xantia HDi Exclusive
405GTX TD

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mat_fenwick
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Re: Flat Accumulator?

Post by mat_fenwick » Wed Apr 30, 2014 11:55 pm

I've actually never done it to mine, and never had the need. Tried it a couple of times on other people's cars in a zero-cost attempt to cure a fast tick time, but with no noticeable effect so would assume it was already seated OK. I wasn't intending to recommend it as a regular task to do, which on re-reading it seems like I may have been.
Image

1993 1.9 TZD Turbo Estate
1996 3.9 V8 Discovery
1993 VW LT35 campervan
1985 Hyundai Stellar V8
2016 Hyundai iLoad

citronut
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Re: Flat Accumulator?

Post by citronut » Thu May 01, 2014 7:36 am

mat_fenwick wrote: I wasn't intending to recommend it as a regular task to do, which on re-reading it seems like I may have been.

no not at all Mat,

i too have never done the ball bearing re/seating trick, but if it dose require doing i dont recommend doing it frequently,

and i have seen it said you must only give it one good bash, and not repeatedly bash it

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)