[Tigers] MC bore

[Bob]

The bolt that broke was not the pressure plate to flywheel attaching 
bolts, but was instead a bolt on the pressure plate nearer the center.   
It retained the pivot for the 'fingers' that cause the plate to retract 
when the throwout bearing was extended.   A master cylinder that is too 
large will extend the clutch fork and throwout bearing too far, which 
can stress those bolts until one breaks (which it did in my case).   It 
was a nice high quality hayes pressure plate too, not a cheapie.    The 
larger bore master (because it moves the slave further per unit of 
stroke on the master) then has a higher pressure required by your foot, 
hence my suggestion to verify both cylinders if the pressure is unduly high.

--Bob
'66 Tiger 382000782

Robert Palmer wrote:
> The master cylinder and slave cylinder bores have nothing to do with the
> force on the pressure plate bolts - just the pressure on your foot.
>
> -----Original Message-----
> From: tigers-bounces+rpalmerbob=roadrunner.com at autox.team.net
> [mailto:tigers-bounces+rpalmerbob=roadrunner.com at autox.team.net] On Behalf
> Of Bob
> Sent: Tuesday, April 29, 2008 12:14 PM
> To: tigers at autox.team.net
> Subject: [Tigers] MC bore
>
> I'm not sure on the master cylinder size off of the top of my head, but
> anyone with this problem should verify the master and slave cylinders are
> the correct size.   My wheel alignment guy once told me 'It takes two men
> and a boy to work that clutch'.   I was 20 years old and thought nothing of
> it, it was what it was.   Years later, the bolts in the pressure plate broke
> due to over-actuating the clutch (MC too big, or slave too small).   When I
> fixed both the hydraulics and the pressure plate, the car was much easier to
> drive, even with a stiffer than stock pressure plate.   Sometime in the cars
> life a previous owner or shop had put on the wrong part.
>
>  
>
> --Bob