shimano Bottom Bracket seals 2

[[email protected]]

shimano BB seals?

The question of what to use for seals when the ball and cone shimano BB
seals fail from mechanical ignorance received no response.

But a length of common 5/8" radiator or fuel hose flew into the
garage and this fits the sugino axle/spindle OD.

I cut the hose mounted on a snug ID fit copper pipe with a socket as
outer guide.

The width was cut oversized 3/16"?. Check the crank arms inner
surface for depression depth. The inner crank squeezes the hose just so
against the cup. Lube with waterproof silicone before mounting.

Cutting goes well with a serrated knife: saw with a slight rocking
motion.

The seals worked on the left side but not on the right. The right CR
side hose disintegrated. Reason for disintegration is unknown-does
valvo synthetic gear lube dissolve fuel or more likely rad hoses? Or
was the disappearance mechanical abrasion? Not much over flow from CR
to axle...?

The BB was repacked and adjusted twice after the hose seal and grease
cleanliness was good. Did castrol marine grease ease out and eat the
seal?

Tweak! The hose (and mil spec hoses or nuke hoses are desirabbble)can
be bearinged by cutting a plastic flat washer(doughnut) to fit over the
spindle for inboard and outboard sides getting pressed up against the
cup and/or crank if this shape is acceptable. Fine roundness and
accuracy of the sugino spindle/axle hole cut is not required-just flat
sealing here

Better! The left side rubber seal from shimano rear MTB hubs, cut with
forms as with the rad or fuel hose, slips over the hose assembly. When
dimensionally eyeballed adequately then squooze between crank and cup,
the MTB seal section diaphragms, seals over the hose.

is the MTB rear hub seal an available part?

On the hose, what are shimano seals made from? A hose from shimano seal
material is the ideal choice.

 

[Nick Payne]

Just cut some sponge into about a 1" diameter circle, punch a hole through
the middle of it, impregnate it with grease, and slide it onto the axle
before installing the crank. With that on the outside, a plastic sleeve on
the inside, and a drain hole in the BB shell, I've had good quality cup and
cone bottom brackets that have lasted for years with the bearings in perfect
condition.

Nick

<[email protected]> wrote in message
news:[email protected]...
> shimano BB seals?
>
> The question of what to use for seals when the ball and cone shimano BB
> seals fail from mechanical ignorance received no response.

 

[[email protected]]

another seal method is oil/gease/alien impervious o-ring plus similar
material shaped into a large flat washer held off course by the HD
o-ring. the flat washer-possible NAPA or industrial supply has it in
stock-is o cut by selecting a pipe (copper?) from floor stock and
grinding the outside to a round knife, and hammering a ring into the
impervious flat washer material.

 

[A Muzi]

[email protected] wrote:
> shimano BB seals?
> The question of what to use for seals when the ball and cone shimano BB
> seals fail from mechanical ignorance received no response.
> But a length of common 5/8" radiator or fuel hose flew into the
> garage and this fits the sugino axle/spindle OD.

-snip-
> Better! The left side rubber seal from shimano rear MTB hubs, cut with
> forms as with the rad or fuel hose, slips over the hose assembly. When
> dimensionally eyeballed adequately then squooze between crank and cup,
> the MTB seal section diaphragms, seals over the hose.
> is the MTB rear hub seal an available part?
> On the hose, what are shimano seals made from? A hose from shimano seal
> material is the ideal choice.

Can't help with replacement Shimano cup seals. New cups with
that type of seal are available from Tange, YST, etc - even
vintage Shimano - next time you need cups. Yes the Shimano
left side rubber covers are readily available and cheap - in
may shapes and styles.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971