> > > When I hit mius 10C I checked. No change. At minus 40c I checked again. I
> > > small change! After three hours the seal was three thou smaller!! THis
> >
>
> R.D. replied:
>
> > About how much metal can be honed from the bore of a master or wheel
> > cylinder during the rebuilding process? I would think it would be hard
> > to take off less than 2-3 thousandth.
>
> To which I'll add:
>
> I have never been able to understand how a hydraulic cylinder CAN be
> rebored at all. Perhaps polished, but if there's serious pitting I think
> the cylinder is scrap. You could, I guess, really enlarge it and SLEEVE
> or reline the thing and thus achieve standard sizes again. Otherwise
> you'd have to go to non-standard seals.
>
> It would have to be a rather rare or expensive part (say off a cobra ;-)
> or somthing) to merit that.
I'm in agreement on the re-honing issue. That's why I asked the
question. I'm a strong believer in replacing hydraulic parts, if
possible, because I think it save grief and a lot of labor in the long
run.
BTW, when I re-did the Cobra's hydraulics a couple of years ago I did
replace everything with new except the calipers, which were no longer
available. In the calipers I replaced the chrome plated pistons with
stainless. In general the parts weren't that expensive because I
shopped around and because most of the parts were common to other cars.
The only parts I had to get specifically from a Cobra parts supplier
were some of the rear caliper pistons. Those were a bit pricey.
To illustrate: I bought two new Girling brake MC for $60 ea. Rebuild
kits cost ~$30 ea. and rubber grease (not included in the rebuild kits)
cost ~$11/tube. Throw in my labor for the rebuilding and the
questionable results and it's a no win for rebuilding, IMO.
I also checked into having the cylinders re-sleeved. The cost of
re-sleeving would have been $50/cylinder; adding $30 for each kit and
$11 for the grease, the result was a no brainer choice between this
option and new.
Roland
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