Gearbox Output Flange Removal

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Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Gearbox Output Flange Removal

Post by Nourish »

I can't get the output flange off my gearbox.
I first made up a plate to fit over the flange and used a 3 legged puller on that - tapping it with a lump hammer- no joy.
I've heated up the flange, I've heated up the flange and quenched it, left it under tension fo a qouple of days - no joy.
So I've machined up a copy of the bmw tool (Thank you Jorg - http://jhau.maliwi.de/mot/gear BMWTransOutputPuller.pdf)
and using an old fork stanchion and a long knuckle bar - no joy - how do I get the bloody thing off?
Kurt in S.A.
Posts: 1647
Joined: Tue Aug 03, 2010 12:08 pm

Re: Gearbox Output Flange Removal

Post by Kurt in S.A. »

This is a mo-fo to get off. I've seen at least two people needed to remove the flange at the recent MOA National rally. Matt Parkhouse was nearly stumped...and he's done hundreds of these. It's on with some serious torque...over 150 ft-lbs. Hopefully the PO didn't use Loctite red on it.

Using that tool from Jorg's site, I recall they thumped the center stud to add some shock to it.

Kurt in S.A.
Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Re: Gearbox Output Flange Removal

Post by Nourish »

Yes - have been hitting it
Duane Ausherman
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Re: Gearbox Output Flange Removal

Post by Duane Ausherman »

It may sound like a 30-06 when it comes free. Yes, they can be very hard to remove.
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ME 109
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Location: Albury, Australia

Re: Gearbox Output Flange Removal

Post by ME 109 »

Heating and quenching should nicely shrink fit the output flange to the output shaft.

Difficult to heat the flange with the tool in the way, but every bit helps. Pointless heating the flange and then trying to bolt up the tool.

Did you use a fine thread for the removal tool's centre hole? I think a fine thread will allow a lot more pressure to be applied?
Lord of the Bings
Duane Ausherman
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Re: Gearbox Output Flange Removal

Post by Duane Ausherman »

Thanks ME 109, I meant to warn against the quenching, but forgot and hit Submit too soon.
Ask the Indians what happens when you don't control immigration.
Ray from Indiana
Posts: 129
Joined: Fri Sep 03, 2010 6:37 pm

Re: Gearbox Output Flange Removal

Post by Ray from Indiana »

I was able get mine off using two lengths of pipe, 1'dia x 4ft long.
One pipe on the bar for the "bmw" tool and one against my chest, pulling the one with the bar toward me. Chest was sore for a few days after but it popped off and put a slight bend in that ~5/8" dia bar...but I straightened out before returning to my friend. But I didn't have any help. If you can have another guy help you it would be safer.
ME 109
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Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: Gearbox Output Flange Removal

Post by ME 109 »

Thunderbirds are GO!

Got an electric heat gun to heat the cover plate? This method of heating is quite OK.
Lord of the Bings
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: Gearbox Output Flange Removal

Post by chasbmw »

Nourish,

A quick plug for the UK BMW club, the club has almost all BMW special tools available to hire for a nominal sum (£5) tomembers and the guy who runs the scheme is very helpful.

I find that my club fees is just about covered by the discount I get from the insurance company for being a member of the club and the western section has negotiated various discounts from local supplier including a 10% discount from Pro Tyre in Bristol. Win win in my book.

We are looking for members to join the join the vintage and classic register, that all BMWs over 25 years old.

Hope to see you in Bristol
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
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jagarra
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Joined: Mon Dec 26, 2011 12:42 pm
Location: Reno, Nevada

Re: Gearbox Output Flange Removal

Post by jagarra »

You may have to take it to a shop that has a press remove.
You mentioned you made a plate to go on the back of the flange, do you also have a small hydraulic bottle type jack. If you threads the plate and made a base plate to go on the bottom of the jack, also threaded and used large threaded rod between to connect the two you could use hydraulic pressure to pull it apart.
1974 R90/6 built 9/73
1987 BMW K75S
1994 BMW R1100RS
1964 T100SR Triumph
1986 Honda XL600R
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