Removing a knackered bottom bracket

[Dogtrousers]

Let us know how it goes.

Or doesn't go.

 

[fossyant]

I binned a Raleigh 531c for this reason - stuck in, but the bike was too big. Excellent opportunity to buy a 653 at the time. Wished I'd kept the frame and bought new now......

Quality tube sets are fetching silly money.

 

[Gravity Aided]

Another for the nut and bolt method. I've never had it fail me, and I've seen some really stuck BBs working on cast off bikes for the redevelopment project.

 

[Globalti]

It's good but don't waste your time spraying penetrating oil all over it then waiting; it makes no difference at all until the piece has started to move and you've broken the bond. Then it's useful. I write as the former owner of a Land Rover, which was built in such a way that it seemed to rely on rust for preventing the hundreds of fastenngs from coming unscrewed. You could soak something in penetrating oil for hours then cut it off with the angle grinder and discover that the threads were bone dry and no oil had ever penetrated.

 

[Tim Hall]

Another for the nut and bolt method. I've never had it fail me, and I've seen some really stuck BBs working on cast off bikes for the redevelopment project.

What I love about the nut and bolt method is the elegant simplicity of it.

 

[Globalti]

Isn't that the beauty of engineering? There's always an elegant way of doing things if somebody can think it through. Read Zen and the Art of Motorcycle Maintenence for more on that.

 

[DRM]

It's good but don't waste your time spraying penetrating oil all over it then waiting; it makes no difference at all until the piece has started to move and you've broken the bond. Then it's useful. I write as the former owner of a Land Rover, which was built in such a way that it seemed to rely on rust for preventing the hundreds of fastenngs from coming unscrewed. You could soak something in penetrating oil for hours then cut it off with the angle grinder and discover that the threads were bone dry and no oil had ever penetrated.

I beg to differ, I use the stuff at work on rusted in nuts, bolts securing pins & rollers etc and it does work on things as shown on the op's photo, as the former owner of an old Land Rover as well, the fixings on them are usually beyond redemption and have be cut off, years of farm crap is a really good feeder for tin worm, as I said spray it on over a couple of days and the capillary action will work down into the threads.

 

[Globalti]

Well I also beg to differ! When a nut is solidly rusted onto a bolt no amount of penetrating fluid will get into the threads and even if it does, it can't magically dissolve iron or aluminum oxide. It takes a physical effort to break that bond and once the bond is broken and the nut is moving, some penetrating oil can sometimes help it on its way along the bolt. However I've also had nuts and bolts that actually tighten up as the nut reaches the exposed part of the bolt, which was rusting freely and the thread "eats" yet more oxide, jamming up the threads to the extent that you end up shearing the bolt. That was why I always went and bought a replacement part before attempting to remove the old one. Typically, if I did manage to get the nut off the bolt intact, I would find the part of the bolt occupied by the nut bone dry with no sign of oil penetration.

So penetrating oil was not often in my Land Rover tool kit but this was my preferred tool:

 

[Gravity Aided]

Angle grinder works when all other methods do not. And the Dremel.