15 mm Brembo master cylinder - rebuild question

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Peter Tourin
Cucciolo - the Lil Pup
Posts: 16
Joined: Sun Nov 13, 2005 6:05 pm
Location: Jericho Center, VT USA

15 mm Brembo master cylinder - rebuild question

Post by Peter Tourin »

I've got an assembly question about the 15 mm front brake master cylinder rebuild kit. On the piston end nearest the lever, there's a washer and a rubber ring surrounded by a metal ring. They're supposed to stay down in the bore, but as the piston moves, they ride out towards the brake lever and finally come off the end of the piston. What's the trick to make them stay in place? It doesn't seem to be a press fit - when I press the metal ring into place it comes loose and rides up.

Thanks - Peter Tourin
'73 Volvo 1800ES
'74 750GT
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BevHevSteve
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special tool

Post by BevHevSteve »

http://www.shop.bevelheaven.com/detail.aspx?ID=42

Peter - it IS a press fit - and easily done with the tool I made and stock [click the link above]
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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Peter Tourin
Cucciolo - the Lil Pup
Posts: 16
Joined: Sun Nov 13, 2005 6:05 pm
Location: Jericho Center, VT USA

Post by Peter Tourin »

If it's a press fit, does the washer that comes with the kit go under the rubber and metal rings, as in the parts manual? When I disassembled, I didn't have one, so I want to make sure before I reassemble.

Thanks - Peter
'73 Volvo 1800ES
'74 750GT
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BevHevSteve
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master cylinder

Post by BevHevSteve »

From the banjo bolt to the lever you go:

*plastic plug
*spring
*piston
*flat washer
*rubber seal with flat part up against washer
*crush washer thing [widest part towards seal]

If you look down inside the master cylinder, youi will notice you see an open bore where nothing touches, then a slightly smaller bore that the 'crush' washer fits into that is only maybe 1 cm deep, then the bore of the master cylinder that the piston rides in.

The crush washer actually presses OUT not in to secure the piston. Using my special tool pushes the crush washer in the direction it needs to go, but doesn;t allow the rubber to get torn etc. Pay attention to how deep the bore is where the crush washer sits, to get an idea of how deep everything must be.
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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
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