Is it possible to soften up old, hardened rubber?

Mark Wright

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Aug 13, 2001, 2:08:32 AM8/13/01

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I've just replaced the carbs on my '81 gs1100 and now I find that I can't
get the air box back on. The left-most rubber boot has hardened to the
point where it is more like plastic than rubber. It no longer stretches
enough to fit over the carb's intake.

I assume the rubber has hardened because of long contact with fuel (the
previous owner left the fuel valve on prime for 3 years, and the left carb
is the one that overflows when the bike is on the sidestand). Is there a
way to restore 'suppleness' to hard rubber, or should I start looking for a
new airbox?

--
---
Mark Wright
mwr...@pro-ns.net

Kaybearjr

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Aug 13, 2001, 9:10:24 AM8/13/01

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>From: "Mark Wright" mwr...@pro-ns.net

> Is there a way to restore 'suppleness' to hard rubber, or should I start
looking for a new airbox?

Solvents present in carburetor cleaner (xylene, for instance) will soften
rubber temporarily...

Ray Curry

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Aug 13, 2001, 11:20:14 AM8/13/01

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In article <A9Kd7.3901$5d4.1...@monger.newsread.com>,
"Mark Wright" <mwr...@pro-ns.net> wrote:

I find glycerin does a pretty good job. There was an Armour All
competitor available in Auto Parts Stores that was mostly glycerin,
advertised itself as the rubber preservative that was clear, not cloudy.
I haven't looked for a long while but if you can find some, try that.

--
Advice is free... and worth every penny.

<F.D.S.>

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Aug 13, 2001, 9:18:38 PM8/13/01

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also, try putting a light coat vaseline on the rubber to make it slide in
easier onto the carb. worked for me. hth.

fernan
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Lee Carkenord

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Aug 13, 2001, 11:48:23 PM8/13/01

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Is there a
> >way to restore 'suppleness' to hard rubber, or should I start looking for a
> >new airbox?

My friend says that Auto. Tranny Fluid softens rubber coarb boots. I
have not tried it, but he warned me to NOT apply too much, or the
rubber will actually get mushy. He says to just wipe a film of the
ATF on....let it soak in for a bit.........

Lee Carkenord

chainsaw willie!

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Aug 17, 2001, 12:35:35 AM8/17/01

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I have boiled carb boots before. It makes them soft enough to install
if you do it before they cool down too much.

"Mark Wright" <mwr...@pro-ns.net> wrote in message news:<A9Kd7.3901$5d4.1...@monger.newsread.com>...

Michael Sloan

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Aug 17, 2001, 8:07:24 AM8/17/01

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There is a product called "rubber renew" (and other brand names) that
softens and renews rubber. It is available at many electronics
stores.

MBillybalfour

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Aug 19, 2001, 12:42:52 PM8/19/01

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I've also heard that tent proofing spray does the trick,leave the rubbers in a
bag with some of the stuff,let it soak in

Pete

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Aug 19, 2001, 6:31:38 PM8/19/01

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Try silicon spray........
Pete
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The Cat

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Sep 2, 2001, 4:10:24 PM9/2/01

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The beets are not rubber to start with. They are PVC and the petrol from the
carbs removes the softening oils from them with exposure. There is all sorts
of ways to overcome this problem but the only way to ensure a good seal to
ensure that no dirt gets into your motor is to fit new ones. They are not
very expensive (Australian $20 each approx.) but it is really good insurance

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