> >Steve,
> >
> >I can't speak for the servo rebuild, but you might want to do some
> >research regarding re-sleeving of master cylinders with stainless.
> >I've heard, but not personally verified the following:
> >
> >1. That silicone brake fluid will seep past a stainless sleeve/cylinder
> > interface.
> >
> >2. That stainless sleeves must be interference fit into the master
> > cylinder and that the aluminum they are made of is not strong enough
> > for this purpose. Another possible issue is the different thermal
> > expansion rates for stainless and aluminum.
> >
> >Roland
>
> Personal experience for 20 years of service with my silicone / clutch slave
> cylinder says this theory as no merit. Perhaps the rubber seals were not
> pre-swollen before assembly by those claiming such data. As to the
> interference fit, I believe that most commercial operations bore to a slip
> fit and use Locktite to complete the seal. I did mine by press fit and I
> can tell you that you better know your dimensions, because if you miss and
> the tube only goes 3/4 into the bore when it exceeds structural and press
> capabilities, you have a very unpleasant mess. I don't think that the
> differential thermal expansion is a problem, but that's feeling not fact.
>
> Tom
The story about SS requiring an interference fit came from someone who
does brass re-sleeving as a sideline business. His sleeves are slip
fitted and bonded. To be honest this could have been based more on
marketing his method rather than on fact since he doesn't do stainless
re-sleeving. I asked him why a stainless sleeve couldn't be bonded
but he never gave me a good answer.
The seeping problem was related to me by someone who had a SS re-sleeve
done and claimed the leak was past the SS sleeve/cylinder interface. It
could be that he just got a bad re-sleeving job, but I also heared from
another party who claimed he had the same problem with a brass re-sleeve.
Again, it could have just been poor workmanship.
Roland
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