Well that's a new one... (Seized Locknut)

[lottafreaks]

Picked up a Dec '72 Schwinn Varsity for $20. I've been tearing it apart to get at the 40 year old internals and make sure it's riding ready for a buddy of mine. First I overhauled the whole front end of the bike. That went by quickly and smoothly. OK, time to move on to the back... but I can't get at the bottom bracket--the LOCKNUT won't budge! I've attacked it with PB Blaster and brute force over the course of a week--nothing. And yes, I'm turning it the right way, though I've even tried the other way around just to make sure I'm not losing my mind. Maybe I am anyway, because I've never had this problem! What's going on? Am I missing something obvious here? Did someone put Loctite on the threads?! What can I do to get the darn thing off? I was confident I could get this bike up to spec after just a day or two of free time but Old Yeller obviously has other plans for me.

EDIT: I got the locknut off by combining pretty much every piece of advice in this thread. I just realized I never gave an update back when I actually freed the darn thing. I borrowed a torch, set the bike up in a work bench, and went to town with my adjustable wrench. It still took a day or two and a lot of treatments with the torch but I finally got that sucker loose.

 

[Walker]

probably the cups were installed when the paint wasn't 100% dry so that's pretty much like loc-tite. Also moisture settles in the bb shell rusting things together. Can you clamp the locknut in a vise and turn the bike. usually works..

 

[user 135]

Can you try applying heat with a propane torch?

 

[motu]

I agree with the heat... But use a heat gun before the blow torch..

Sent from my Nexus 7 using Tapatalk 2

 

[Wildcat]

If you have a big wrench large enough for the locknut, secure the cranks and give it a couple taps with a hammer. A big pipe wrench may do the trick also. It should turn clockwise to loosen.

 

[B607]

It should turn clockwise to loosen.

Left hand thread. Maybe that's the problem. Gary

 

[lottafreaks]

Thanks for the responses guys, I'm going to get my hands on a torch later this week and see if that does the trick. And yes, I know they're left-hand threads!!

 

[Bicycle808]

Good luck using the heat. Get some kroil, too, if you can. Gun shops seems to carry it. I think that's the best penetrating oil available to the general public. I've yet to see a seized locknut on a set of OPCs, but it doesn't really surprise me. Someone might've put that on without lube back in like 1976, and time/neglect did the rest.... You'll get it off, though.

 

[mikeeebikey]

Left hand thread. Maybe that's the problem. Gary

Another thing i have done is using a flat punch(dull chisl) and a hammer, tighten the cone. It will probably toast the bottom bracket.
As was said, left hand threads, turning the nut clockwise looking at it loosens.

 

[mikeeebikey]

And if that didn't work, sharpen the chisel and split the nut.

 

[Wildcat]

I've had them rusted on the crank and they break free with a few hits of the hammer. It's a thin lock nut is why they usually break free. The ones I've seen overtightened have been the toughest to get loose.

 

[jerrykr]

If you get a good wrench on it, use a cabinet clamp to clamp the wrench on so it can't slip off. put a block under the crank so that it can't move, they hit the wrench with a brass hammer. In other words set things up so that the only thing that can move is the lock nut, and wail away.