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Subject:Re: Bled the Clutch
Date:Tue, 3 Jan 95 14:35:38 AST

>
>So now I'm thinking about rebuilding the slave cylinder.  Somebody
>said rebuilds weren't always successful.  But the dealer wants $34.00
>for the rebuild kit and $171.00 for a new cylinder.
>
>If anyone has any thoughts on this let me know.  It's getting colder
>in the garage and I want to cure this before I go into hibernation.
>
Try for an aftermarket rebuilt unit, and good luck. Rebuilding isn't hard, 
but you must be fussy about it. Clean the outside thoroughly, scrub it. then 
teardown the unit, wipe it shiny clean and inspect the bore. It should be 
free of pitting, deep scratches, or other obvious defects. Drag your 
fingernail over the surface to check how rough it is. If all seems OK, and 
the only sign of wear and tear is a dull (but smooth) region where the 
piston has been sliding, it is rebuildable. 
        Refinish the cylinder bore. You need a small honing tool to do a 
decent job of this, since the new seals will slide/seat best against a 'new' 
flat/smooth surface. Buy/borrow one, they are <$20 at your FLAPS. Follow the 
directions carefully, go slowly and have patience( you need an electic 
drill, variable speed, BTW). Use lots of clean brake fluid to 
lube/clean/flush the unit, get rid of ALL the carborundum grit left from 
honing.  Honing will restore rather bad surfaces, but if your cylinder bore 
wasn't too bad to begin with, you may be able to hand polish instead using 
Crocus cloth, a very very fine sandpaper. Saves buying a hone, but could 
cost more if it doesn't work well enough, your labour/frustration is worth 
something after all, even if it's not monetary.  You are trying for a figure 
eight pattern inside the bore (with hone also), so wrapping the cloth around 
your little finger and twisting the cyl. around/up-down is what's needed. 
Don't add scratches along the length of the cylinder, as fliud will then 
leak past the seals.
         Your description of a clunk makes me suspect that you have a well 
worn area where the piston has been travelling. Getting that area flat will 
not be possible by hand, even if you get it smooth, (yes, there is a 
difference!). New softer seals may fill/fit in the worn area better than the 
old ones, or they may leak, maybe after a month or so. Remember, cleanliness 
counts here, be prepared to use a pint of new brake fluid as cleaner, 
remember what the dealer wants for a cylinder?, use fluid as needed! The $31 
seems high for a single seal, and dust boot, this is dealer price I assume. 
Try for the rebuild kit from FLAPS also. Taking your dissassembled cleaned 
unit to the FLAPS may get you some useful free advice, .ie too far gone, 
chuck it out! It'll also get you the right size hone, and maybe seals.    tim s.

PS: are you SURE it's the slave cyl. It'll take half a day to do this, 
drive-in to drive-out.