Freehub freezing?

[Nebulous]

Its very very cold here this morning, with a thin skimmering of snow. I went out for a quick blast and the circulation in my hands shut down quite painfully.

However the main reason I gave up was my freehub was slipping quite dramatically. At one point it was spinning as freely forwards as it usually does backwards. I was wondering if it might have frozen? I guess that would be a bad sign, as there really shouldn't be water in it, should there?

I've never dismantled it - so that will probably be my task this afternoon. I suppose with a year and about 4000 miles in it probably needs it. I'm kind of working on the if it's doing okay leave it alone principle, but I am beginning to need some repairs.

 

[gbb]

Definately frozen, once it thaws it'll almost certainly be ok. But, it may reccur, it may be the freehub is on its way out anyway at 4000 miles.
No clear answer...i think if it were mine, i'd be preparing to replace it.

 

[Nebulous]

Well I'm stuck at pretty much the first hurdle.

I've removed the wheel, QR, cassette and now I can't get into the axle. Both ends have a smooth aluminium cap, which I presume is pressed on, with a small hole in the side, but I can't remove it. Freehup seems pretty rough.

 

[Will1985]

Try a 5mm allen key in each end.

 

[Ian H]

Are there not nuts both end of the axle? It might be useful to post a photo.
Roughness probably indicates worn bearings. Easy to replace, especially if they're cassette. You might get away with cleaning and relubricating the pawls.

 

[Zoiders]

You can't get it apart to get at the pawls if it's Shimano, you would have to fabricate a two pronged tool from a steel tube as Shimano stopped making them.

What you can do though is have the freehub body off and soak it in oil to thin the grease back out again if it's gummed up, some people have drilled ports to pump grease in with as well.

The other option is a new one, this however does not rule out the problem of grease thickening in the cold and making the pawls stick, urinating on the cassette has been known to be a quick roadside fix though.

 

[Nebulous]

Hi guys - thanks very much

I've had the wheel on its side, and dripped oil through from the end of the freehub. Lots of brown gunk came out of both the bottom of the freehub and the other end of the axle and the freehub seems much smoother now. Here are a couple of photos of the end of the axle to show what I mean. There are no nuts, and the end of the axle doesn't take a 5mm Allen key. Wheels are from a specialized allez elite with unnamed hubs and mavic cxp22 rim.

 

[ColinJ]

Pee on it ... Seriously, if you get absolutely stuck somewhere with that problem, it's worth a go to try and thaw it out!

 

[Ian H]

if the oil went through that easily then the seals are obviously not terribly efficient. Regular lubrication of the kind you describe will keep the hub going for a while, but it might be worth thinking about rebuilding the wheel with a nicer hub.

 

[steve52]

move to warmer regions? i would if i could

 

[baznav]

To get the end caps off you have to undo the grub screws in the picture and the end caps will pull of and then the freehub will pull off, however when they do the grub screws up in the factory they burr the axle and that can make getting the end caps off a bit tricky but they will go.

 

[Tynan]

how cold was it exactly?

surely moving metal, with even some grease/oil is going to have to get pretty bloody cold to be affected

surely it's just knackered?

 

[Nebulous]

It wasn't that cold minus 4 maybe. Clearly the metal wouldn't freeze, but frozen water around moving parts could make them stick. I did about 25 miles on Sunday and its running better than it has done for a while, so you could be right that its knackered. I'm quite happy to change it, but I need to get the bloody thing off first!

I'd also like to replace the bearings, but I'd rather not buy new wheels at this point. I have a vehicle MOT issue that makes this appear rather insignificant and that will need fixing first.