Seized Pedal Arms

Author
Discussion

chrisj

Original Poster:

517 posts

262 months

Thursday 26th July 2007
quotequote all
I'm busy rebuilding my old Kona to be used for commuting.
The pedal arms simply refuse to come off the bb axle.
This wouldn't really be a problem, as the bike is pretty much worthless and won't see anything other than light road use.
The problem I have is that the bb, a cartridge bearing type, has decided to unscrew itself from the frame.
The only way to get the tool in to tighten the cups is to remove the immovable pedal arms.

I've tried pentrating oil brute force to no avail.
Any pearls of wisdom for this?
I've stripped the removal threads on pedals on old bikes, so I don't want to do that again.
Would applying heat from a blow torch help?

Greendubber

13,807 posts

210 months

Thursday 26th July 2007
quotequote all
chrisj said:
I'm busy rebuilding my old Kona to be used for commuting.
The pedal arms simply refuse to come off the bb axle.
This wouldn't really be a problem, as the bike is pretty much worthless and won't see anything other than light road use.
The problem I have is that the bb, a cartridge bearing type, has decided to unscrew itself from the frame.
The only way to get the tool in to tighten the cups is to remove the immovable pedal arms.

I've tried pentrating oil brute force to no avail.
Any pearls of wisdom for this?
I've stripped the removal threads on pedals on old bikes, so I don't want to do that again.
Would applying heat from a blow torch help?
You could try heating it up, however being as the crank arms aluminium I'd be a bit carefull about that.

I had the same problem a few years back and ended up having to trash the cranks to get them off. Just keep soaking with pentrating oil and see that happens. I presume you're using a crank extractor by the way?

T

chrisj

Original Poster:

517 posts

262 months

Thursday 26th July 2007
quotequote all
Yes, I'm using my trusty crank extractor.

Oh well, I'll keep plugging away.

Cheers.

groomi

9,323 posts

250 months

Thursday 26th July 2007
quotequote all
Have you got something like a ball-joint seperator?

With the bike upside down, put a protective rag around the frame and crank, then in the gap between (assuming is is big enough) position the seperator so that each 'fork' is either side of the BB spindle. Give it a good thwack with a lump hammer and retrieve the crank from the broken patio door window. smile

mat205125

17,790 posts

220 months

Thursday 26th July 2007
quotequote all
Are the cranks and the BB junk, and you just want them off of your frame?

72twink

963 posts

249 months

Thursday 26th July 2007
quotequote all
Have you tried putting the bolts back in but not tight and then having a gentle ride outside your house, that might budge them. The most elegant solution and the one I use is to get a crank puller it never fails but then you say you've stripped the threads in the past so if the puller looks like it's not going to work alone wind it up tight and then use a soft faced mallet to tap the hub of the crank at 90 degrees to the line of the BB axle (remember though that any shock will feed into the BB so don't go mad) - I've seen this done on stuck hubs on Salsbury car axles. As with any taper lock you may be in for a wait and may have to wind up the puller and keep tapping over a period of time until it un-seizes.

Ideal opportunity to replace the BB too !!

Tony

sjwb

550 posts

215 months

Thursday 26th July 2007
quotequote all
Apply extractor to pedal arm and apply load.
Evenly heat around the pedal boss, to about 150 celsius.
Smartly tap the head of the extractor bolt.

chrisj

Original Poster:

517 posts

262 months

Friday 27th July 2007
quotequote all
Crank, pedal arm and bb are all good, I only need to remove them to tighten the bb which has come loose for some unknown reason!

I'll give some of these alternatives a go over the weekend.
Fingers crossed.

Cheers.

Parrot of Doom

23,075 posts

241 months

Saturday 28th July 2007
quotequote all
If you have a crank extractor it shouldn't be a problem. You just screw the tool as deep into the crank as it will go, and then screw the extractor part against the bottom bracket with a big spanner. It should come off no problem, if it doesn't I'd start looking at hacksaws....

mk1fan

10,648 posts

232 months

Monday 30th July 2007
quotequote all
I think the 'gentle ride' option is the best one.

groomi

9,323 posts

250 months

Monday 30th July 2007
quotequote all
Any success then?

Rico

7,916 posts

262 months

Monday 30th July 2007
quotequote all
I had a similar problem once and it was due to there being a spacer left in the crank (that the bolt tightened down onto) that made it impossible to remove.

Removed the spacer... and the crank came off easily banghead

If all fails, ask to borrow a bike shop's crank extractor. It'll have a long arm and be easy.

chrisj

Original Poster:

517 posts

262 months

Wednesday 1st August 2007
quotequote all
I managed to get the pedal arm off last night using a 3 arm hub puller.
Didn't work for the cranks though, I couldn't get the puller to stay still.
Tried heat, no luck.
More oil, still no luck.
I think I'll probably bring it to work and try and press it out.
A 50Te ram should have enough capacity to either pop them apart, or obliterate both items.
I'm at that 'nothin to loose' stage now anyway, so may aswell give it a try.

chrisj

Original Poster:

517 posts

262 months

Friday 3rd August 2007
quotequote all
Got the crank off this morning.
Only took a 1.1Te push to do it.