Low Lhm, LHM and clutch problems

[Miguel]

Hello.

I'm new with XM, my car didn't come with manual.
It's a 1990 XM, can you tell-me different brands of LHM fluid, so I can buy one.
I 'have a leak in the system; the low level can produce problems in the clutch?
How can I purge all of the oil in the system?

Thank you in advance.

[techmanagain]

I am sure that if you ask, someone in the Club can supply a driver's manual for you.
The best LHM and the cheapest is bought direct from the Citroen Main Dealer. What is your location? Is it in the UK?
If your car is a 1990 model it will have a manual clutch, not hydraulic.
Please sign off your messages witrh your car model, engine type and year to make it easier for the correct answer to be given to your questions.

[jorgy9]

Hi Miguel,

I don't know if there's officially a method for purging ALL the LHM from the system. I think it would not be possible to achieve that because the oil is distributed to so many circuits...But you could achieve purging *almost* all the oil if you took off a pipe, for example one that feeds high pressure to the front height corrector, and leave then egine running till it pumps out the last drop of LHM in the tank while trying to raise the car. Of course you would need a ramp to do this. Again, you will have oil left in other parts of the system. I don't know if it's very important to get the last drop of old LHM out, as the new LHM is so many litres that the old residual will be just a small %. One important thing after having put fresh LHM in, is to bleed the brakes of the car, using the bleeding points on each caliper. The brake circuit is a dead-end and this is the only way to get old LHM moving overthere. You also need to do this to bleed out air that is trapped inside.

regards
George

[UFO]

Are you sure there is no user manual? It does not live in the glovebox, it is stored in a drop down flap which in a RHD car is just above the passenger's legs and has a rotating clip holding the flap shut.

This "no manual with car" problem occurs with Xantias too, for a similar reason.

[Miguel]

"egine running till it pumps out the last drop of LHM in the tank"

Won't this cause problems on the pump?
I'v seen some hydraulic piston pump that need lubrication provided by the hydraulic fluid.
The hydraulic fluid used in the system also have a lubrication function, and to remove some termal energy from the system.

Is it safe to remove the oil while running the engine?

[techmanagain]

Please don't try to drain all the oil from the system! I can visualise you being on this clubsite for days afterwards if you do.
Just syphon out the majority of the fluid from the tank, then remove it and clean it out with petrol , finishing by swilling it out with LHM. Clean both the filters in the LHM tank with petrol before replacing them in the tank. Fill the tank with about 4 litres of LHM.
At the pump-end of the pipe from the tank, remove it to allow you to prime the pump fully. Return the pipe to the pump. Open the pressure relief valve about one turn only and start the engine. Close and open the pressure relief valve several times while the engine is running. Close it finally, and wait for the car to rise with the engine running. It may take a little while. Set the car at maximum height......Then bleed all the brake calipers, starting at the rear, until clear , bubble-free LHM comes out.
Finally top up to the correct level before lowering the car to normal height.

Check the LHM level frequently while bleeding the brakes. You should have at least 2 litres available for this procedure and final topping up.