My power steering gear box seems to have a slow leak around the plate on the top. Is it a major job to replace the o ring? I've tried lucas stop leak, that didn't work.anyone had one of these apart?

 

not that hard of a job.....the 4 bolts on the top, and the adjuster ....that's about it.....except for the specific square-cut o ring which you will need, and more fluid to topoff with.
the o ring comes in the seal kits that all the parts guys have available. Clean everything off good before you start so as not to let dirt into the steering box, if you have a few extra bucks around , now would be a good time to replace the power steering hoses.....another frequent leak source

 

Hello,

I’m coming in very late !

The steering box of my Disco 1 was also leaking, and the hoses under hydraulic pressure were become very brittle (your hands where covered with steering box oil when touching them.
So my garagist replaced the steering box and the pressure hoses ; he didn’t want to fit a “refurbished” steering box while those often stay leaking around the sealing rings (forvexample when the housing has traces of scars around these sealings).
But after a few days, the new steering box was leaking again ; so,my garagist ordered again a factory new example and replaced the p of “new” steering box ; all under guaranty, I hadn’t to pay for it.
Now, for about 3 months the new steering box is still working without leaking (and without horrible screaming sounds).

Kind regards,
PierroDisco