Xantia SX 2.0L H.D.I. LHM pump problems

[stevestix8]

Hi All,

Been a while since I last posted and the car has been great, is 27 yr old this year and still going strong.

Am posting as I have what appears to be the slowest possible leak from the underside of the LHM pump.

Have checked all the pipes and nuts on the top of the pump and there does not appear to be a leak from there. I feel under the pump and there is a small amount of LHM under it. Have cleaned the area and just looked again and there is still a small amount of wet under there.

It has not registered on the LHM Levels and I haven't put any in for some weeks so it must just be losing a very small amount.

I replaced the rear spheres recently (cost me about £130 for 3 spheres) as these had gone hard (around 10 yr old) and were possibly causing the problem, the rear suspension is back to as good as it should be but after checking again today there is still some wet under the LHM pump???

Any advice anyone? There are large round nuts (with Alan key head) on the bottom of the pump where it looks like the leak is coming from, are these adjustable?

Cheers in advance,

Steve

[mickthemaverick]

I think you may find the answer by reading through this thread: viewtopic.php?p=395411#p395411

[xantia_v6]

You can find more reading material with this search link: googlesearch?cx=000757428655895309399%3 ... gsc.page=1

I recommend using Bitcoin o-rings, rather than the original HDPE, and I go 0.1mm larger cross section, especially on the 2 big o-rings on the pump outlets.

In my experience, it is the pump outlets that leak first, you may be able to replace those without removing the pump.

[stevestix8]

Hi,

Thanks for responses.

As far as I can see the 2 pump outlets are where the leak is coming from.

Best info says the 2 types of O rings to get are:

O ring listed for the 6+2 pump are 16x1.9 and 19x2.4.

So I would want 2 of those 19mm x 2.4mm O rings.

Xantia_v6 are you saying I need to go 0.1mm bigger (width) than this, i.e. 19mm x 2.5mm?

Have found these on ebay:

https://www.ebay.co.uk/itm/293213858499 ... R6Ka9OiXZg

Might just be the solution, cant hurt to order some for £3.00.

Steve

[xantia_v6]

Yes, 19x2.5, but get Viton, not nitrile. They are also available from eBay vendors.

[stevestix8]

Hi again,

Cheers for advice, you're right that Viton is a better synthetic rubber than Nitrile.

Have ordered pack of 5 (still only £3.00) of the Viton O rings (19mm x 2.5mm), hopefully leak will be sorted.

https://www.ebay.co.uk/itm/293529629998 ... R6Tig-6XZg

Do I just unscrew with an Allen key? (is it 8mm?), much fluid loss? then coat new ring in LHM and re-fit?

Steve

[xantia_v6]

The smaller (16mm) rings are fastened by Allen headed plugs (which are biblically tight). The larger (19mm) o-rings are mounted in hollow plugs which come out with a normal socked or spanner (once the pipe is removed).

[CitroJim]

The smaller (16mm) rings are fastened by Allen headed plugs (which are biblically tight).

Giving those a good direct dead-blow thump with a decent hammer can help loosen them - a tip I picked up from a well-known specialist in this discipline.

It works too

Any O rings you get I'd advise you test them for LHM resistance by soaking them in a small jar of the stuff for a few days. It's amazing just what LHM will eat!