Friday, 10 July 2009

floating

another in my occasional series: Useful Guides To Fixing Things On Moggies, And With Pictures Too, What's More



After I changed the Trav's rear axle hub bearing and oil seal back in May , I've been intending to take the wheel off and check that everything was OK. I finally got round to it, and found that everything was pretty good, but there was a bit of float on the hub- that is to say, it could slide inward and outward rather a lot. The Workshop Manual says that the bearing should protrude beyond the face of the hub; in fact, it was about 1mm below the face, which felt like quite a lot when I rocked it to and fro.

So I dismantled it again.


I got some heavy cartridge paper and measured the combined thickness of ten sheets. This gave me 3.5mm. So I reckoned that three thicknesses would be about right. I drew around the bearing and cut out three paper shims, like this





...and then reassembled the hub.



According to my calculations, the bearing face is about 0.5 mm proud of the hub face, and the book says it should be 0.025 to 0.102 mm. I'm hoping that the fudge factor will take the discrepancy on board. And I'll check it again next week or so, to make sure that it isn't leaking.