Another MOT failed, this time due to leaks on the hydraulic Active Cornering Enhancement system. I've always known this would be a weak point, I've avoided any problems for the last two years and this is why I was so careful on my lap around the 'Ring last year.
A brief history on ACE It was fitted to Discovery Its to reduce the body roll on corners and I suppose it's pretty ahead of its time, thinking about how Clarkson was so impressed by the hydraulic anti-roll on the Range Rover Sport when it came out much later. It uses hydraulic rams from and rear to twist the anti-roll bar as required.
This is a slightly crappy video of how it works:
[video=youtube;ENByJ1-zx6k]https://www.youtube.com/watch?v=ENByJ1-zx6k[/video]
And this is supposedly the effect it has compared to the competitors of the time (which I take with a pinch of salt):
It's leaking from the main control valve block and the rear hydraulic ram, something that might at first impression seem easy to fix but the valve block sealing relies on hard lines that corrode in place and plastic seals that are generally a bit shit. It's leaking like this, not as bad but bad enough:
I was able to tighten the lower of the two nuts fairly easily so maybe, just maybe, this will stop
that leak.
There's a second leak on the banjo bolt seals on the ram itself which, while being easy to replace, come with their own issue as the system must be bled after replacing them. This is done using the diagnostic computer, which I actually have. However, the documented procedure involves using a 4 post lift as you need to disconnect the link arms to allow the ram to be extended to the fully extended 'bleed' position, which essentially bypasses the ram to allow air to be removed from the system. The truck must then be lowered to run the bleed procedure.
This is pretty much what it does to shake the air out of the system:
Now if tightening that nut doesn't stop the leak then things will start to get a lot more involved. I first have to remove the rear hoses, which according to all . information will break in the process so will have to be replaced in some way. Said information says that just replacing the seals and plastic collets won't fix the leak, so I'm probably looking at using proper hydraulic fittings. The existing ports can be tapped out like this for fittings:
One option is to try and re-use the existing hard lines, using compression fittings like this:
Or go for full-on hydraulic hoses like this:
I'll see when I go back tonight and check the leak.