I still haven't managed to get the leak done so topped up the LHM today.

I was amazed to find the cap was just a loose fitting piece of plastic on the top. Not really ideal for keeping debris out. Is this right?

I'm sure the old CX's and BX's used to have a tight fitting cap.

XM tank cap is about the same as that on a BX, and Xantia for that matter. Just sort of sits there with the breather hose dangling out the top.

Yes, that's about it.

Thanks Craig. Seems in their haste to produce this super technically complicated car someone forgot to design a decent tank cap.

You're telling me. I opened the bonnet of the Xantia one day to find it had had a nice LHM explosion all over the top of the engine. I wondered where it had come from, and found the LHM cap just sitting on the edge of the tank.
Not sure what caused the issue, but it had blown the cap right off! If it had been a screw one it wouldn't have happened.

I never did find out why it did this.

Hi Ciaran,

I think you'll find that a diaphragm in a sphere was punctured and the resulting emission of gas into the hydrauilic piping found its way back up to the LHM tank. It is possible I suppose that the loose fitting cap is there as a kind of 'explosion' relief in the event that 60 bar gas escaping from a sphere is vented safely by blowing it off.

Only a theory....

Cheers

noz

Hi Noz,

That would make a lot of sense, as I recently noticed the front spheres had gone hard as a rock, despite the fact the car had been sitting unused for quite a while, and it had new front spheres a year ago, and has done next to no miles since.

I'll be replacing the two fronts and the accumulator before it goes back on the road next month, methinks...

Cheers

P.S good point about the vent cap being a bit of a safety valve, may be a blessing in disguise really!