A DA7C Beginner’s Guide

TOOL TO ASSIST REAR HUB REMOVAL

 

One of the most important jobs on a well-used Seven is to keep the rear hubs firmly fixed to the half-shafts. Now the delight of working on an A7 is that you really don’t need a vast array of specialist tools - generally only a hammer and, if that doesn’t work, then a bigger one! However, the odd gadget helps. For the rear hub, you pretty well must have an A7 hub-puller - make sure its screwed well down onto the hub and tightened firmly, then hit with the above. But, before you do that, you have to get the half-shaft nut off - now this is where ‘the gadget’ comes in! You’ve got your big spanner on the half-shaft nut but of course you have to stop the hub rotating. Often used are mates with a big Stilson on the hub (urgh!) or stout lengths of wood or metal jammed between the wheel stubs and the hub with the free-end jammed against the floor. A kinder way is to take an old brake-drum and weld a thickish metal bar about an inch or so wide and 20 inches long (nothing critical) to its face leaving the stud-holes clear - preferably use an old tin drum leaving the rarer cast ones for we who like hydraulic brakes! Once you have this beauty, hey presto, it immediately replaces the mates, Stilsons, bits of wood and scraped knuckles in the above procedure - just bolt it on like a regular brake-drum and tighten or loosen the half-shaft nut to your hearts content! On tightening- several things. The real engineers will lap the hub onto the half-shaft taper (obviously without the key) - not too strenuously as it will eventually go too far in! Then assemble with the key and check with ‘engineers blue’ that the tapers are in contact and not held apart by the key. If the latter, file the top of the key until blissful mating is achieved! - the hub is supposed to connect to the half-shaft through the taper and not the key. If you don’t do this, or the nut not fully tightened, hard use will result in the half-shaft keyway breaking apart with consequent loss of drive and a significant reduction in your bank balance! Finally, on the issue of how tight is tight? I asked this self-same question to Vince (who knows everything!) whilst checking my nuts (actually ‘Rhubarb’s’) after an especially rough section of the Gibraltar Run - his response was to leap up on the very long spanner I had in place and jump up and down: ‘that’s how tight’ he said! You do of course have to line up the split pin hole which might require different thickness washers.

Ian Mason-Smith