[Healeys] Overdrive Question

[Austin Healeys List]

Hi Michael,

The other aspect is that the hydraulic pistons apply about a ton of
force forwards to the brake ring when engaging plus a rotational force
which will move things around a bit. Then there is the differential
expansion of ali and steel. The best sealant in the world won't be any
use if the flanges keep opening up and moving around. Maybe the
factory just gave up on trying to seal it, after all there are plenty
of other intentional leaks on these cars.

Andy.


On 11/7/16, Michael Salter <michaelsalter at gmail.com> wrote:
> Hi Andy,
> The thing is that there is no mention of the use of any type of sealant on
> the clutch ring in any of the literature that I have on the overdrive
> units...
> Hard to imagine but I have never seen evidence of any on the virgin units
> that I have disassembled... I think it was just a dry joint!!!
> Michael S
> BN1 #174
>
> On Sun, Nov 6, 2016 at 4:06 PM, Austin Healeys List <
> austinhealeyslist at gmail.com> wrote:
>
>> HI Michael
>>
>> It has nothing to do with the studs stretching and everything to do
>> with the aluminium housing flexing. It only needs to move a tiny bit
>> to unstick the sealant and after that there is no longer anything
>> stopping the oil weeping out. I'll run an FEA simulation on it some
>> time to show just how flexible the ali case is.
>>
>> btw, Yamabond, Kawabond, Hondabond, Suzukibond etc are all OEM names
>> for ThreeBond sealant.
>>
>> Andy.