A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Need advice on bottom bracket repair



 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #10  
Old January 9th 17, 12:31 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 4,018
Default Need advice on bottom bracket repair

On Sun, 8 Jan 2017 17:27:33 -0500, Frank Krygowski
wrote:

I too have had much better luck with PB Blaster or old-style Liquid
Wrench than with WD-40.


Same here. WD-40 may have 2,000 uses but it's only good at what it
was originally designed to do; displace water.
https://wd40.com/img/WD-40_2000_uses.pdf

I hate suggesting ideas that I haven't tried, but if you're willing to
take the risk (and not sue me), this might actually work.

Better living through chemistry. In this case, we have a steel cup
and an aluminum frame and bottom bracket. My guess(tm) is the threads
are clogged with iron oxide (rust) and aluminum oxide (white crud).
The trick is to find a chemical that will attack both without trashing
the base metals. One thing *NOT* to use is CLR or various household
calcium/lime/rust removers. The acid will attack the two oxides, but
will also destroy the base aluminum threads. It may come apart, but
you probably won't have any threads left in the aluminum.

So, what to do. Oxalic acid and water mix will attack both the rust
and the white crud. It's a rather large molecule, so it may take some
soaking of the bottom bracket in the oxalic acid solution to get some
penetration. If you feel ambitious, heat up the bottom bracket
slightly, slop on the oxalic acid, and get out of the way. Tiny air
spaces in the threads will produce a partial vacuum as it cools, and
suck in the liquid. It won't suck much but it might be enough to
soften whatever is jamming the threads, especially if you can move the
steel cup with the now broken bottom bracket wrench. Oxalic acid will
bleach anything it touches, especially your clothes, so please wear
gloves and protective clothing.

When you put it back together, I suggest a little Never Seize:
http://www.neverseezproducts.com/neverseez.htm
http://www.neverseezproducts.com/antiseize.htm
to prevent a repetition of this exercise. However, if you do use some
kind of anti-seize or grease, be careful not to over tighten the cups.

Good luck.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
bottom bracket advice [email protected] UK 0 November 12th 07 02:36 PM
bottom bracket advice Ben Fitzgerald UK 12 December 9th 05 09:45 AM
Bottom bracket advice [email protected] Techniques 0 June 28th 05 03:41 PM
Bottom Bracket/General Frustration advice please? Saint UK 9 April 12th 04 12:11 AM
advice sought on bottom bracket NC UK 7 August 8th 03 06:48 PM


All times are GMT +1. The time now is 12:17 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
Copyright 2004-2022 CycleBanter.com.
The comments are property of their posters.