[Healeys] BN2 back axle

[Bob Spidell]

Just to confirm: Hubs from a later car, say, a BJ8 will completely 
interchange with a BN2 hub?

How would one determine a correct gasket thickness? There's no way, 
IIRC, to get a feeler gauge in there.

TIA,
Bob

On 3/23/2024 5:25 AM, john harper wrote:
> Gary
>
> The BN2 rear hubs are a bad design relying on very accurate 
> machining of the depth of the bearing location and an accurate bearing 
> width. Tolerances are very tight and it is hoped that a gachet of 
> correct thickness will make a good oil seal and at the same time grip 
> the bearing outer from turning in its housing.
>
> This problem was addressed by the manufacturer and an extra grove was 
> machined in the face of the hup. Into this grove is fitted an 'O' ring 
> that will seal the gap between the hub and half shaft. This will seal 
> a wide range of tolerances and at the same time ensure that there is a 
> good grip on the bearing outer.
>
> If available the best solution is to find hubs for later big Healey 
> and fit these together with 'O' rings.
>
> Another solution is to run a continuous ring of liquid gasket around 
> the face of the hub before assembly. This is also the only effective 
> seal on early BN1 hubs.
>
> All the best
>
> On Mon, 18 Mar 2024 at 18:02, warthodson--- via Healeys 
> <healeys at autox.team.net> wrote:
>
>     The work shop manual refers to a specific dimension that the paper
>     gasket must stand proud of the steel ring spacer.
>     The gaskets that I received from a well known supplier were too
>     thin. I made my own & have never had a leak or a bearing failure,
>     so far, 15-20 years!
>     Gary Hodson
>
>     On Monday, March 18, 2024 at 11:15:39 AM CDT, Bob Spidell
>     <bspidell at comcast.net> wrote:
>
>
>     Tom Monaco told me he's replaced a large number of spun axle
>     bearings--IIRC he said 'a hundred' or so--over the last few years.
>     I'm not sure exactly what you'd look for that presages that
>     problem, but something to keep in mind. It's not particularly easy
>     to get the requisite torque on the big eight-sided nut that clamps
>     the inner race; knocking it on with a hammer and chisel isn't a
>     good solution (I use a purpose-made large socket and a 3/4" air
>     impact driver). They can spin in the hub as well.
>
>     Moss sells a reg. seal for $2.79 and a 'premium' for $21.99; I
>     couldn't tell you the difference except the cheap one is a 'no
>     name' and the 'premium' was a (generally) good brand (maybe Timken
>     or SK; I don't recall). Worth it or just 'marketing?' Beats me,
>     but given the hassle of this job I went for 'premium.'
>
>
>     On 3/17/2024 5:23 PM, Michael Oritt wrote:
>     What Bob says.
>
>     The inner seal on the axle is the critical piece and if there is
>     wear on the sealing surface you will need to fit a Speedi-Sleeve
>     or similar repair piece.
>     BTW SKF and others make what they call semi-sealed or sealed
>     bearings with plastic or fibre pieces on one or both sides of the
>     bearing but since the sealed ones are not filled with oil I have
>     never understood how they are supposed to get lubrication.
>
>     Best--Michael Oritt
>
>     On Sun, Mar 17, 2024 at 5:06 PM Bob Haskell
>     <rchaskell at earthlink.net> wrote:
>
>         Mike,
>
>         The bearings are lubricated with the rear axle oil.  No
>         grease.  Oil flows between the axle shaft and the axle housing
>         to around to the bearing.  Yes, the paper gasket has to be oil
>         tight. The oil seal keeps the oil from lubricating the brake
>         shoes.
>
>         Bob Haskell
>         Austin-Healey 3000 roadster registrar
>
>         On 3/17/24 16:13, mike brooks via Healeys wrote:
>>         Can someone explain how the hub oil seals are meant to work.
>>         They are inbord of the hub bearings. Are the hubs meant to be
>>         packed with grease? ( the service manual suggests they
>>         should, but the same manual doesn't tell you to pack the hub
>>         with grease when changing hub bearings and seals). Is the
>>         back axle oil intended to pass across the oil seal to the hub
>>         bearing? If so, then the paper gasket in the hub flange to
>>         half-shaft joint will need to be oil tight.
>>
>>         Thanks in advance for any help.
>>
>>         Mike Brooks
>>         56 BN2
>>         Scotland
>>
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