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Hi,
I have a totally spannered bottom bracket.
It was stuck last time i had a look at it (2005). The the plastic non drive side came out when i had a go at ie last time but the actual bottom bracket was stuck fast.
Tonight the plastic side has smashed when I tried to take it out.
Its got half the teeth left and has moved about 2 turns.
Its been soaked in gt40 for the last week.
Steel frame and the original square taper bottom bracket from 2001- its never been out of the frame.
I'd prefer to avoid heating the frame if possible, even if I did heat the frame how could i get the half smashed bottom bracket shell out?
Any suggestions?
how are you holding the bottom bracket tool in? I normally use a QR through the hole in the middle to clamp the tool into the BB and then use a socket in a long wrench on the tool while I stand on the frame. Or if you don't have a socket and long wrench then clamp the tool to a solid object and turn the frame.
Might work on the remaining plastic bit as well as the metal part. Make sure the QR has a bit of give so it can actually undo when doing the plastic bit and then keep backing it off a bit. For the metal part no need as it's all part of the same unit.
GSF do a really good penetrating oil with colloidal graphite which I have found works very well on seized parts as it keeps to lubricate as it comes undone.
Hi,
Its a solid axel on square taper- being able to stick a qr through would have been ace.
I'll have a look at the penetrating oil, theres a gsf round the corner:)
crank bolt to hold the tool on with some washers.
vice/long tool.
No point in getting plastic out until drive side is out.
Cynic-al,
Pity I didn't think of the crank bolt to hold the bb tool on, that might have stopped it cracking.
Whats the vice for- holding the frame?
I thought it would be best to get the plastic bit out first as it would make it easier to get the other side out?
vice for tool, hold and twist frame.
It's always the steel side that seizes, the plastic bit isn't holding it in significantly and will come out easily afterwards.
You are turning it the right way?
I'm very sure I'm turning the right way- I got it wrong installing a bb in a brand new frame once. Not an experience i want ot repeat
I'd take the plastic side out so you can fill the frames BB shell with penetrating oil for a few days prior to your next attempt.
did you saw plastic?
If so then heat is your friend, you can pour out the fitting with a blow torch (Some old bb's had plastic fittings)
The plastic part is tapered IIRC and thus can act to wedge the BB in place - you can try removing the other side but IMO taking the plastic side out first is best. Wahtever works for you tho
ahh I did wonder if you had a hole all the way through. I just remembered my BB was an Octalink so had a hole through. In which case yes the crank bolts or a bolt with the same thread if you need longer.
Getting some heat/cold involved might help to loosen things up too - some rag tightly wrapped around the frame metalwork (heat this up with a kettle of boiling water to get the frame part to expand), then a blast from a freezer spray (the sort of thing used by plumbers to freeze pipes) on the bottom bracket bits inside to get them to contract and hopefully loosen.
Also worth a "all else has failed" try - if you've got a power drill with a hammer-only facility put a chisel or point tool in and try and get some tangential blows onto the bottom bracket shell - similar has worked for me getting well-stuck-in-frame steel seatposts moving.
Pour a kettle of boiling water on the BB shell. This has worked for me in the past.
[url= http://www.ribblecycles.co.uk/sp/mtb-bmx-bike/tools-Tacx-T4415-Bottom-Bracket-Cartridge-Shimano-Nonspline/TACXTOOL420000000000 ]One of these[/url] and a foot long 32mm spanner did the trick for me when I needed to shift a square-taper BB that had been in situ for a decade.