Hydraulic Pump Seals

nesssalmon · Post by **nesssalmon** » 12 Oct 2006, 20:14

Hi

One of my Hydraulic pump seals is weeping. (One right on the top) You can see LHM pulsing as the pump works. This is only a tiny leak of LHM on the drive in the morning.

Is this seal replaceable? or does the whole pump need changing? Is it a fairly easy job?

Many thanks in advance
Robert 8)

AndersDK · Post by **AndersDK** » 12 Oct 2006, 21:58

With the introduction of the multirib beltdriven pumps on XM & Xantia - the seals in these pumps are replaceable.
These pumps are completely differently contructed than their older counterparts found on GS, BX & CX - which were sealed units.

Mandrake · Post by **Mandrake** » 13 Oct 2006, 07:09

Replacing the seals on the pump is a relatively easy job....

If you can get the pistons to unscrew!!

I took my pump off looking for a fault and to replace all the seals, heres a picture of it sitting in bits:

http://homepages.igrin.co.nz/simon/imag ... ppump1.jpg

I had no trouble getting the pump apart (the three long bolts that pass right through the body) and I also had no trouble removing the two pistons which drive the suspension/brakes. (the two large hex head plugs)

However the 6 pistons that drive the power steering and have a Torx T50 head simply would NOT budge without going well beyond what I thought was a safe amount of torque, so I ended up leaving those ones alone.

(They weren't leaking, so rather than risk damaging the pump I left well enough alone)

Admitedly I was trying to do it with the pump held in a vice and you can't hold it very securely there because of the shape of the pump, but if its only one of the top easily accessible pistons leaking then you could do it in situ without unbolting the pump from the engine, and the brackets that hold it would hold it more securely than a vice.

Just make sure you fully depressurize the hydraulic system. (Don't forget the pressure regulator bleed screw!) With the system depressurized its safe to remove the pistons, just be wary of the fact they have a spring, ball, and clip in them, and the spring may try to jump out. (It's only a very weak spring)

The following page has some useful pictures including the assembly order of the spring, ball and clip in case you mix them up:

http://www.citroenthai.org/pump62B.htm

The seals for those pistons are green in colour - you can just see a couple in the top of shot near the white rag in the photo...

By the way, to anyone reconditioning a pump, you've probably found out that Citroen don't sell the seal for the face of the triangular flange (bottom right on the pulley) - well guess what - a standard square section sphere neck seal is perfect for the job!! (The thickness and diameter is just right)

(The original seal is the middle sized o-ring to the left of the tray, which was squashed flat and hard from age...)

Regards,
Simon

nesssalmon · Post by **nesssalmon** » 13 Oct 2006, 11:35

Thanks for your replies. Mandrake that’s a really detailed description and very helpful.

Cheers
Robert