Here are some tips:

Firstly a hub leak is not the end of the world. Wear in the bearings can occur and affect leakage so test them before teardown.
To do this jack up the wheel try to push /pull the wheel through the 12/6 o'clock plane.A slight amount of movement is permissable. If there's lots get an assistant to depress and hold the brake. If the movement goes away its bearings , if not its steering pivot pins related..

If its appears to be the hub seal remove the drum & brake shoes. Maintain their respective positions relative to the back plate. With the shoes removed look at the bulge at the top of the back plate, there's a STEYR emblem on it. If the internal shaft holding bolts have "let go” they will tear into the casting causing a crack or blow out resulting in leakage. That costs quite a bit if you can’t get it welded from a specialist.

To remove the back plate take out the allen cap screws and tap the thing off with a block of soft wood & a hammer. Remember to release the brake line.
Now you need tools. Get a generic 4.5" leg gear puller and buy safety goggles or a face shield from favourite home improvement store, you'll need 'em.
Remove the three bolts from the retaining plate holding the gear and then start pulling. Warning Chips can fly from the gear, hence the goggles etc. In other words: put them on before you start to do the work!
If some fool has used Loctite on the gear you may need heat to break the bond, best of british luck mate, you may break the gear. SO DONT USE LOCTITE WHEN RE-ASSEMBLING THIS STUFF!!
So you've got it off. Now you will need a 5/10lb plastic mallet to beat the drive flange out of the bearing. Do not be tempted to press it out you will bust the backplate.

Now you can gain access to the seal.
This is a standard seal available from NAPA & the seal stores so are the bearings 6208/C3.
Re-assembly is in reverse order, lubricate the seal with grease upon rebuilding. OK, use Loctite if you must on the fixing bolts.
Use some sealant like the "right stuff" on the backplate face.
Check that the bearing are not spinning in their housings, if they are you can use that Loctite to "glue them into place”.
Having assembled, the shoes need to be adjusted so remember the threads are right handed. Keep that in your minds eye as you tighten them up & release.
Use three wheel nuts to tightened down the drum to square them to the drive flange.This makes adjustment more easy & accurate.

Lubrication: I am not going to be pedantic about this but don’t use synthetic oils, if it leaks it destroys the brake linings. Expensive.!!! We use a Shell Spirax 75ep, this keeps the heat down in the hub and reduces that annoying hub pressurization that gets posted about from time to time.

Contributed by Dennis Williams, LinDen Engineering