How to adjust the Burman Steering Box. Step by step instructions for your Alfa Romeo. The ZF is here
It is important to check the oil level at least once a year in your Burman steering box. Remove the oil filler cap and pour a good quality 90w GL-5 gear oil to top up. It is the same oil as you should have in your gearbox. A modern 80-90W is is OK too, but I always use Shell Spirax as in 1967.
The shaft and the other moving parts inside the box should be totally below the oil level. The oil filler plug/hole might be lower on some Burman boxes. Don't worry, just keep the box full with oil.
If it is leaking, I know some owners that have pressed quality grease inside and then the proper oil on top of all, to prevent leaks. This should last for a year or so, but sooner or later you will need to replace the seals.
There is at this point no need to remove the steering from the Alfa yet. It can be adjusted quite easy. Most parts are in stock at www.highwoodalfa.com
There are not so many parts inside. The shaft/arm (A) will turn as the steering column (B) rotates and the cup (D) affects the bearing (C).
To minimize the play, the cup (D) should be pressed down by the very strong spring (E). The play may be adjusted by adding or removing the shims (G).
The shims are positioned under the oval top cover on the top of the steering box.
Remove the cover along with the shims underneath.
When removing the oval top cover, note that the cover is under pressure by the spring (E) and sometimes jumps up a bit.
Replace the small oval cover along with the shims and the short spring. When refitting, you will most likely need to press it down quite hard to get the bolts in place.
The shims are the key to the play in the steering, but double check so you still have the steering self-centring.
Do not overdo it so the steering becomes too heavy and hard and does not go back by itself when driving.
The spring (E) should press down the shaft (A) so that there is no play at all. The shaft pressure effects the round "cup" (D). The shims are marked as (G). The parts (A) and (D) are somewhat conical and the springs takes the play.
When the play is adjusted, refill the box with tranny oil and check for leaks. Oh, always replace the plastic filler plug so that no water or dirt may get inside the box.
That's how it all works.
I have some additional photos about the Burman box to help you understand. For a complete description of how to overhaul the Burman, read more here. And remember to top up with 90w GL-5 gear oil every year.
The front bearing to the left may be adjusted by removing the shims too.
Seals for the shaft may be either O-rings or traditional oil seals. The oil seal in the Burman is 40x28x7mm. In case you have an O-ring, it should be 28x4mm. 28mm being the inner diameter.
Finally, a drawing of the parts. Please click to enlarge.