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MG Midget and Sprite Technical - Frog master cylinder
currently overhauling my master cylinder and I have eventually freed the final piston and additional gubbings...
Question - the many books and parts list seem to indicate that the secondary cup sits behind the boot fixing plate and in-front of the actual piston. In the attached picture (red circles) mine seems to have a seal / boot on the actual piston shaft, it actually locates on the step just down from the end of the piston. Can anyone shed any light on this - ie are mine just wrong? do the replacements come in a different arrangement?
The yellow circles are highlighting the main boot on both pistons. I'm assuming these should both be the same size? one of mine looks quite a bit bigger and is less "stiff" than the other. Im assuming this is just aged rubber and they should in fact be the same? Slipped in a second question there.
|Hi Alan are both the bores the same size? In the photo one of the pistons looks bigger?|
|Hi Bob, think that's down to my lack of photography skills, both pistons are the same diameter and the bores are original - no sleeve.|
Your photos look correct to me. To the best of my recollection my frogeye master cylinder has the seals in the same positions.
|Thanks Simon - so to replace they just need a really good stretching to get them over the piston end?|
|Yes they are tight. Plenty of brake fluid as lubricant will help.|
This thread was discussed between 02/11/2015 and 03/11/2015
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