Very little.
The mechanism for the sliding side door required replacement, and the lower edges of the bodywork/wheelarches seemed particularly rust prone, with bubbling becoming obvious very quickly.
A fantastic machine all round, everything you want in a van. Really quite startling performance, plenty of space, narrower than a Transit so easier to manoeuvre in small places.
At first the column gearchange seems a bit daunting if you've never driven one before, but it soon becomes second nature.
Enthusiastic driving when unladen can result in axle tramp/wheelspin, but in most conditions it was great.
All the power you need, and I used to get 35 mpg.
Being a later 5 speed, motorway cruising was easy and relaxed - I never found out what the top speed was, well into 3 figures I would imagine.
It's a pity that these series 3 Hi-ace vans are now a very rare sight in the UK, they are worth far more in the export market to developing countries, thanks to their tolerance of overloading and legendary reliability.
If you have one, cherish it.
Thanks for your review, I bought one of these 2 weeks ago, spent a few days doing a bit of work on some surface rust and it's currently having a brand new 4y engine fitted.
Considering the age of this vehicle I'm amazed at how well everything has held up. The gearbox is perfect and very tight, there's no excessive drive train noise and it's super straight.
I'm looking forward to a long relationship with this van, oh and a long (1860km) drive down the East Coast of Australia in about two weeks (nice to get acquainted).