Master cylinders

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fosworth
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Master cylinders

Post by fosworth » Wed Oct 24, 2018 4:46 pm

Please can someone confirm what size the brake and clutch master cylinders should be. The ones on the car I am rebuilding are 5/8 Brake ( large unit ) and 3/4 Clutch ( small unit ). Its a 64 L/C and my research suggests the brakes should be 3/4.
John

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Keith Halstead
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Re: Master cylinders

Post by Keith Halstead » Wed Oct 24, 2018 7:17 pm

For the P14 calipers brake master cyl should be 0.7"

Clutch is 5/8" I think.

fosworth
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Re: Master cylinders

Post by fosworth » Wed Oct 24, 2018 7:58 pm

Thanks Keith, that confirms my thoughts and makes the job much easier due to availability of suitable master cylinders.

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tommy
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Re: Master cylinders

Post by tommy » Wed Oct 24, 2018 9:43 pm

64 car brake master cylinder should be 0.7" and clutch master cylinder 5/8"

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Peter Meyer
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Re: Master cylinders

Post by Peter Meyer » Thu Oct 25, 2018 8:31 pm

I think the .7 are hard to find. There is an old factory service bulletin about this and the wrong size can give you lock up problems I'm lead to believe.

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tommy
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Re: Master cylinders

Post by tommy » Thu Oct 25, 2018 11:22 pm

Very early cars had 0.75" brake master cylinder and 0.75" rear wheel cylinders, but this was changed to 0.7" brake master cylinder and 0.7" rear wheel cylinders. I believe this was due to rear brake locking problems, but even with the correct 0.7" master and wheel cylinders fitted, my car had too much rear brakes and was prone to end up sideways in heavy braking situations.
Tommy

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Peter Meyer
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Re: Master cylinders

Post by Peter Meyer » Fri Oct 26, 2018 3:44 am

That's what I hear.....

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Michael Winstock
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Re: Master cylinders

Post by Michael Winstock » Fri Oct 26, 2018 8:58 am

Peter...you must have very good hearing.....10000 miles to Northern Ireland?
There I go again Keith.....getting way off the original subject!

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Peter Meyer
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Re: Master cylinders

Post by Peter Meyer » Fri Oct 26, 2018 8:31 pm

The internet is an amazing thing Michael. They even post old Lotus Cortina factory bulletins. Even in Australia!

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