Help (again)!!! - rear input shaft seal removal IMPOSSIBLE

jpod

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Here we are again. I posted at the weekend for help removing the gearbox. Now it's off, thanks Haynes manual for lying to me.

The rear input shaft seal needs replacing (the seal that separates the clutch slave cylinder from the gearbox) and I cannot get it out.

I was told to get some hooks to pull it. Tried that, no chance.

I did what I was told not to do: I drilled some small holes and inserted self tapping screws. I used vice grips to pull on the screw and it would not budge. When I say I pulled, I have the gearbox out on the floor, and I'm pulling on the vice grips while standing on the box... not quite full strength yet, but with quite a lot of force.

I read somewhere that there is a bearing right behind the seal and I'm worried that the screw might be catching that... so I don't want to pull like a madman just yet.

Does anyone have some wisdom to pass on? PLEASE :bow

While you're at it, any advice on how to put a new seal in will be appreciated.
 
I have a couple of quality right angled picks. Very strong and they don't bend.

I insert them down in the inside part of the seal. Twist 45 degrees and pull.

To insert new seal use a long socket the same diameter as the seal and tap it into place..
 
Thanks Steptoe. I can try that, I just bought something that might work as you say.

I am still concerned at the amount of force required; does it sound right that I have two screws in, 180 degrees apart, and pulling with two sets of vice grips with my back arms and legs into it and nothing moves at all?

I would have thought that if the seal doesn't move, I would at least be ripping it appart and blowing out the screws.

any idea how much space there is between the seal and the bearing?

Edit: I have just ripped a screw out, but the seal didn't move. The top of it is starting to look damaged, but no movement.
 
can sometimes help if the screws are attached to a slide hammer :nenau

i had a stuck rear crankshaft oil seal on a guzzi that i nearly ran out of room to drill more holes once :eek:
 
Cookie, That doesn't sound promising...

I've been probing around in there at this point and I'm getting a bit concerned. I've pretty well ripped up the rubber bits on top, but since the new seal hasen't arrived yet I don't know how thick the seal is or what it is made of. f When I use a metal pick to tap through where the rubber is damaged, I hit something hard. I hope the seal has a hard component to it, because otherwise, I'm afraid I've been drilling into something in the gearbox :eek:

And, I have a hard time believing I'm doing this right, when Steptoe suggests that a couple of right angle picks and a tug should do the job...

For now I'm going back to the Haynes manual to see what's involved in opening the gearbox :tears
 
Cookie, That doesn't sound promising...

I've been probing around in there at this point and I'm getting a bit concerned. I've pretty well ripped up the rubber bits on top, but since the new seal hasen't arrived yet I don't know how thick the seal is or what it is made of. f When I use a metal pick to tap through where the rubber is damaged, I hit something hard. I hope the seal has a hard component to it, because otherwise, I'm afraid I've been drilling into something in the gearbox :eek:

And, I have a hard time believing I'm doing this right, when Steptoe suggests that a couple of right angle picks and a tug should do the job...

For now I'm going back to the Haynes manual to see what's involved in opening the gearbox :tears

Haynes manuals have two good uses, lighting fires and holding open doors. Get the proper manual, at least you will be working from correct info. If you can't get the seal out I think it would be better to take the box to someone who can rather than stripping the whole lot down

John
 
can sometimes help if the screws are attached to a slide hammer :nenau

i had a stuck rear crankshaft oil seal on a guzzi that i nearly ran out of room to drill more holes once :eek:
This is a small thin seal
I think you are in too deep!
 
I've got the BMW repair manual, which is useful in a high level sort of way - it assumes a lot of knowledge on the part of the user (logical since the intended reader is a BMW mechanic). However, I am not a BMW mechanic or even close to that level, so the tips, tricks and in depth explanations of the Haynes manual help, even if they get it wrong sometimes. Just have to think it through and double check that what is written makes sense.
 
I think I agree with the Welshman.

I just saw this:
0003.JPG

http://lh5.ggpht.com/_nvRconY-y0U/Sn3tIFtLa8I/AAAAAAAAAfE/Mlrq1yZ-o0I/s800/0003.JPG

from this thread:
http://www.advrider.com/forums/showthread.php?t=491635

From the above photo, the seal appears to be flush with the end of the input shaft (the shiny metal rod sticking out is the push rod). My seal is a bit further down the shaft and I'm starting to wonder if it is in fact the seal or if I've been drilling into a bearing :blast

I suppose it could be that the seal got pushed down at some point and because it's thin, it's up against the bearing. Either way, bad news.

Not sure what to do next... I will post a photo of my box and see if anyone has an idea of what I'm looking at.
 
Why not take it to your local independent bike shop and get them to remove it, probably take them 2 minutes and a fiver to buy the mech a drink:beer:

May as well take the new seal and get them to install that at the same time, job done:thumb2
 
Well, I was considering taking it to someone but who? I split my time between London and Durham, and normally I would take it to Steptoe, but at the moment I'm in Durham.

Any GSers in or around Durham who might know a good independent mechanic in the area?
 
The seal is a fairly deep one, around 6-7mm IIRC. I have one in the garage somewhere so will take a look. There is a gearbox bearing behind it, but you have to go fairly deep to get it.
The main thing is not to scratch the inner shaft trying to remove it.
The seal has a metal outer ring encased in rubber. The outside of the rubber is ribbed (to allow for heat expansion of the gearbox when in use). This can make it tricky to pull.
With mine it was quite reluctant to move at first. I destroyed most of the seal in fact. This actually made it easier to get out in the end.
First off I would get the little spring that lives around the edge of the seal out of harms way.
If you have no joy with picks, get a long flat blade screwdriver and round the end off. You can then use this to lever against the outer edge of the seal. Move around the seal edge as you do it. It takes a fair bit of pressure, but should suddenly start to move.
Heres a link to show you the depth of the seal:
http://www.ukgser.com/forums/showthread.php?t=149381&highlight=clutch+slave+cylinder+seal
This is the new seal. Maybe an upgraded part as mine was a black seal like yours. I used the little device in the pic to set my seal depth.
 
If it doesn't want to come out, push it in further for a few mm, that will brake the bond, take depth measurements first.

Then insert a longer screw and use a claw-hammer to lever the seal out.

Works a charm on stubborn seals. :D

Paul.
 
Well, I was considering taking it to someone but who? I split my time between London and Durham, and normally I would take it to Steptoe, but at the moment I'm in Durham.

Any GSers in or around Durham who might know a good independent mechanic in the area?

How do. Been following your thread with interest. I'm Durham.
Call mick Kendrick on 07828 281003, he's your man.

Good luck
 
fatnfast, thanks for the detailed post; that's exactly the information I was after. I will get hold of a suitable screwdriver and grind it bit and try your method.

I just tried PaulRS's very logical suggestion of breaking the seal by hammering it in a couple of mm. The seal moved very, satisfying after watching it stubbornly stay put for two days. Unfortunately, it is still taking too much force and my screws are ripping out of the seal. Oh well. I will get screw driver now and grind it into the right shape.

Michael, thanks for letting me know about Mick Kendrick. I will continue to abuse my gear box for a bit longer, safe in the knowledge that there is backup at hand.

Thanks to everyone for their help so far. I will report back in a bit. :beerjug:
 
fatnfast, thanks for the detailed post; that's exactly the information I was after. I will get hold of a suitable screwdriver and grind it bit and try your method.

I just tried PaulRS's very logical suggestion of breaking the seal by hammering it in a couple of mm. The seal moved very, satisfying after watching it stubbornly stay put for two days. Unfortunately, it is still taking too much force and my screws are ripping out of the seal. Oh well. I will get screw driver now and grind it into the right shape.

Michael, thanks for letting me know about Mick Kendrick. I will continue to abuse my gear box for a bit longer, safe in the knowledge that there is backup at hand.

Thanks to everyone for their help so far. I will report back in a bit. :beerjug:

Just be careful of the mounting face, it's easy for people to get carried away with levering the seal out and end up using the gearbox case as a fulcrum. Damage here can be difficult to sort.

Good luck

John
 
If it doesn't want to come out, push it in further for a few mm, that will brake the bond, take depth measurements first.

Then insert a longer screw and use a claw-hammer to lever the seal out.

Works a charm on stubborn seals. :D

Paul.

Claw hammer :rolleyes:

You've obviously never had to remove this particular seal. If you had you'd know you'd be working in a deep recess about the size of a thumb. :blast
 
Under correction, I reckon the 'claw hammer' idea would work in conjunction with the "longer screw'... if the screw protrudes from the cavity, then you can use the claw hammer, levering on the face where the slave cylinder mates with the greabox case (protecting the mating face, of course).
 
VICTORY

I finally got it. What a pain in the ass. I ended up fashioning a tool as suggested by fatnfast using a grinder wheel and file, being very carful to round off all edges.

IMG_1670.JPG

Here is the result:

This is the outside face that I mangled in my attempts at extraction

IMG_1673.JPG

This is the inside face, which also holds the metal spring you see in the photo

IMG_1672.JPG

I inspected the inside surface and it seems fine, with no significant scoring. Hopefully, the new seal will do it's job better than the last one; I'm not looking forward to doing this again any time soon.

Thanks everyone for your help... now to put it all back together. :thumby::thumby:
 


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