Removing stuck crank arm; heat?

[Daddy Pig]

Evening everyone.
I'm in the process of trying to remove a stuck non-drive side crank arm from a square taper axle. Threads are all ok. No amount of leverage seems to move the crank, even though I gave it a soak in some GT85 overnight. So as it's an alloy crank on steel axle, my next plan is to apply some heat with a blowtorch and try the standard removal method again when it's good and hot.
Question is, if this works, will the crank be ok to re-use afterwards if it's been well heated? Or anyone have any other solutions? Help would be much appreciated...thanks in advance

 

[marc two tone]

Re:

One day i'll do a walkthrough on this subject, just need a stuck arm....


Heat is an option but you have get it really hot and work quick bearing in mind you may have hold the arm for at some point, take care...

Ive seen some beat-the -hell -out -of -it methods that are ok if you are repainting etc...

For me, if you can waste the arm and replace it, then cut it off.
Start with a hacksaw just outside the visible axle end running parallel with BB axle, keep going until you are 90% through, hold arm at peddle end and press toward the chainstay and back, it should give, if not keep chopping and try again. It's the least suspense ridden way of getting it off and a one tool job. Not many(if any fluids will help here). Try track the blade 2-3 mm from bb axle.
And you are not ordering stuff that may/may not work.

If it's a posh arm, race face, L and M, then i'll shut up and leave the room

 

[Daddy Pig]

Thanks Marc

It's certainly nothing special, but a nice Ridgeback 24" wheel / alu frame for my daughter. I didn't want to go too mad with the heavy tools for fear of damaging the frame or stripping threads etc. I probably could lose and replace the arm; I guess that's worse-case scenario, so not too bad really.
I might still have a go with the blowtorch (and a pair of thick rigger gloves); will let you know how it goes

 

[Skyfarmer]

I'd say you don't need to get it that hot. Hot air paint stripper heat is more than enough.

Are you using a pullet tool or just trying to tap it off? If yo are just tapping it...get the proper tool, you won't regret it.

If you could get some...try some of that freeze spray that freezes water in pipes for plumbing repairs. Freeze the axle ...get it really cold while heating the crank...apply heat at the pedal end or half way along and allow the heat to travel down.

 

[old_coyote_pedaller]

Re:

I used a car ball-joint splitter to remove a stuck non-drive arm. There's the usual type with bolt that I used but there's also the type shaped similar to a tuning fork that you hammer in to gap. If you use this type you could put thin alloy sheet in between it and BB/crank arm to minimise damage.

 

[coomber]

Re:

You can buy a v or u shaped thing to slide it off. Can't think what they are called.

GT85 or wd40 won't do anything. Need thick.penetrating oil.

I would just cut it accross the top by the bottom bracket with a hacks and once cut prize It off.

 

[Daddy Pig]

I actually broke the 14mm socket on my old remover tool just trying to get the bolt out! Got that out with a socket & big wrench, but the arm is staying put. For now...

 

[Westfailure]

Re:

This may sound really dense but have you removed the central securing bolt?

I know, I know, I know who could be that dense? Well I was that soldier. Managed to get the bugger off as well but mullered the crank arm.

 

[Skyfarmer]

Well if you do have the proper puller then the next thing to do is just wait.

Soak for a few days with penetrating oil.
Fit puller and tension it up as tight as you can.
Add a load of heat to the crank arm, then walk away. Maybe then come back in a few hours and try again.

The combo of oil, pressure from puller and differential expansion of alloy and steel will eventually let it loose.

 

[xxnick1975]

if bolt is out ride it up hill in a high gear a few times, then over some bumpy tracks, ideally far from home without tools - bound to fall off then.

one of the few benefits of bulleye cranks - they never get stuck!