Struggling to separate the two halves of the drive shaft

[Molly]

I now have my swingarm on the bench but I'm struggling to separate the drive shaft halves so as to remove it. I imagined the two halves would telescope easily in and out of each other but not so. 

Have I misunderstood something here? Any advice appreciated. 

Apologies if this has been previously covered. I did look but unsuccessfully. 

[docc]

Yes, they should slide freely apart. Yours has, evidently, rusted together. A good find and important to address!

Perhaps an overnight with a penetrating product, then heat and some tapping with a persuader? 
Otherwise, penetrating oil-> heat-> hydraulic pressure pumping grease into the center Zerk?

[Molly]

  On 10/31/2024 at 5:11 PM, docc said:

Yes, they should slide freely apart. Yours has, evidently, rusted together. A good find and important to address!

Perhaps an overnight with a penetrating product, then heat and some tapping with a persuader? 
Otherwise, penetrating oil-> heat-> hydraulic pressure pumping grease into the center Zerk?

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Thanks Docc. I had the same with a BMW drive shaft last year. Was a pig to get it to release but got there in the end. 

This started-out with me just wanting to grease the front UJ. Next thing I've half the bike on my bench and am busy getting parts vapor blasted and changing bearings. I don't mind. It all needed doing and we're heading into winter so it's a good time to be doing it. 

Thanks again. 

[docc]

Just a reminder if too much grease is left in the shaft cavity, the halves will not go back together or there will be restricted movement interfering with suspension travel.

Nice to hear you enjoy "the process." 
Your spineframe will love you back!   

[docc]

  On 10/31/2024 at 7:00 PM, Molly said:

Thanks Docc. I had the same with a BMW drive shaft last year. Was a pig to get it to release but got there in the end. 

This started-out with me just wanting to grease the front UJ. Next thing I've half the bike on my bench and am busy getting parts vapor blasted and changing bearings. I don't mind. It all needed doing and we're heading into winter so it's a good time to be doing it. 

Thanks again. 

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Ah, yes, greasing the front Uni-joint can lead one to desperate measures . . .

[Molly]

  On 10/31/2024 at 11:11 PM, docc said:

Ah, yes, greasing the front Uni-joint can lead one to desperate measures . . .

 

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LOL. I can see I'm treading for the first time down a well-worn path. The swingarm itself needs a good clean-up. The powder coat is flaking all over the place. I guess I'll get it blasted and recoated. I've a 2000 Cali arriving next week too so there'll no doubt be more to do there. I just want to retire and spend all day on this stuff but my Mrs said something about bills.... 

[Molly]

Just in from the garage. No way I can get those two shaft halves separated whilst it's stuck in the swingarm. Decided to disassemble a UJ. It wasn't keen.... Don't seem to be able to press one side in far enough for the cap on the other side to protrude sufficiently to get a grip on it. 

It's battling me but that's OK. Any tips on taking apart the UJ. Haven't done it before but I've watched a ten minute YouTube video.. ;-) 

[Molly]

I think this is stuck....

 

 

[audiomick]

Doesn't look all that good...

[docc]

I read somewhere that a mix of 1/2 acetone + 1/2 automatic transmission fluid is a potent penetrating oil. Drizzle, heat, wait, repeat (maybe add a little vibration/percussion) while leaving the contraption in that tension state . . . perhaps, alternate with striking it into compression . . .

Once apart, there is an O-ring in there that will need renewing.

[Lucky Phil]

Heat and working it back and forth and some penetrating oil/concoction of your choice. Two things. You need to destroy the oring in the sliding section so the penetrating oil can access the splines and the heat needs to be applied to the bevel box end of the shaft as the female end is just a shield over the splined portion. 

[Molly]

  On 11/1/2024 at 10:32 PM, docc said:

I read somewhere that a mix of 1/2 acetone + 1/2 automatic transmission fluid is a potent penetrating oil. Drizzle, heat, wait, repeat (maybe add a little vibration/percussion) while leaving the contraption in that tension state . . . perhaps, alternate with striking it into compression . . .

Once apart, there is an O-ring in there that will need renewing.

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Thanks Docc. I'm leaving it overnight to see if there's any movement. I'm left wondering how I didn't notice this when riding... 

[Molly]

  On 11/1/2024 at 11:25 PM, Lucky Phil said:

Heat and working it back and forth and some penetrating oil/concoction of your choice. Two things. You need to destroy the oring in the sliding section so the penetrating oil can access the splines and the heat needs to be applied to the bevel box end of the shaft as the female end is just a shield over the splined portion. 

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Thanks to you too Phil. I'm heating with a paint stripping gun. Might have to get a butane torch. 

[gstallons]

Uhhhh , have you greased the grease fitting at the slip yoke to push it apart ?

[Lucky Phil]

  On 11/2/2024 at 12:55 AM, gstallons said:

Uhhhh , have you greased the grease fitting at the slip yoke to push it apart ?

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Worth a try but if it's rusted together it's unlikely to work. A grease gun can only exert so much pressure, certainly less than a pair of hydraulic jacks plus my brand new shaft assy isn't totally sealed. When you slide it apart you can feel air escaping. There's a bleed hole somewhere.

Phil 

Edited November 2, 2024 by Lucky Phil