MGB Refilling the steering rack

I had already changed the gaiters on the rack as described in my previous post- I was left with a lot of greasing tasks- which frankly I loathe as its impossible to do them neatly. I had the usual battle to get grease to stay in the king pins rather than squeeze out around the nipples but succeeded eventually and then turned my attention to the steering rack- with I may say some great trepidation.

The rack apparently requires about 200 mls of EP90 gear oil. Its not the oil or the quantity thats the problem but the fact that the rack is filled once in the factory and its oil ought never to need changing- unless as in my case it had all disappeared! Anyway this means the factory have not seen fit to provide either a drain or a fill/level plug and there are basically only two ways of filling the rack: through a gaiter or through the top pressure plate.

Filling through the gaiters involves jacking the car up on one side so that you can fill the higher gaiter and the oil will hopefully run into the rack not out over the floor. The problem with this is that it involves taking off a gaiter again and potentially stretching the join as an oil can or similar is introduced underneath. Probably best to detach the wide end of the higher gaiter and feed oil directly into the rack. However a bigger problem for me was that the car was raised under the front crossmember- it was therefore raised equally and I didn't want to lower it only to raise it again- so top pressure plate it has to be.

John Entwistle has a great video of this but by 'Eck its messy!!!
Anyway my approach follows and I was pretty pleased with it.
Firstly you need some room so detach the lower mounting for the undertray- actually this would help with the sump bolts which is a job I need to do later but for some reason the undertray hasn't been made readily detachable. However for this  job just bending the tray out of the way helps a lot.

 This is the top pressure plate- it holds a piston spring loaded plunger in contact with the rack. I don't know what it does! Anyway the top plate is held on by 2 1/2 inch bolts

 They come out fairly easily, and there's a collection of shims beneath that regulate the pressure on the plunger. Make sure you find them all- initially I thought I had only one but I found a second later.

 When the plate is removed the piston is revealed just sticking out of the rack- you can just get your fingertips on it and pull it out...

 ...and it comes away- its positioned with the cutout across the rack

 Digging around inside the hole let me retrieve the plunger and its internal spring.

 which I reassembled for safekeeping into the piston

I have a Sealey oil syringe to put the oil in- I'm told an old ketchup bottle works as well.

 Anyway I loaded it up with 200 ml of fresh gear oil and carefully (and slowly) started squirting the oil into the rack. In Johns video he uses a pressure pump and its really messy. This oil is viscous- it will take time to settle in the rack so don't try to introduce it too quickly. I got 200ml in easily with no spillage  and didn't have to keep moving the rack- go slowly and the oil finds its level. I put a little bit more in until I got some overflow and then stopped, cleaned up and reassembled.

Re-insert the piston and plunger- I found it stood a little higher on rebuild but the pressure plate pushes it back down. Make sure you have all the shims before refitting the top plate.

Steering does feel easier- it had been getting quite stiff and although there are probably several reasons for that, lack of oil definitely wasn't helping!