Over-ambitious AP11 stripdown 1993 (with Park)

[pebbles]

Hi there, I am a dreadfully ambitious but novice spanner man.
So why am I going in deep where angles fear to tread. Sorry cant answer that except that I like a challenge and have a thirst for knowledge and a desire not to be beaten.

So here it is...

I have a broken Auto (with Park) that I need to get back on the road soon cos my other mini's manual gearbox is sounding like it will brake too.

So the car is a 1275 and has 75K on it and has been for the last 4.5 years (26K miles) as good a gold and daily used but died two weeks ago.
Since then I got the lump out and decided to go against popular opinion and leave it as an auto. But after a couple of quotes over £2K I thought it best to take stock and try a way before giving up and going with the manual conversion.

Anyway heres a photo of the conservatory dining table and the reverse brake band.

Attachments:

[limby2000]

Nice one Pebbles, i think most of us on here have the same conviction regarding auto,s. It appears you,ve done all the hard part (strip down), virtually all parts are availiable either jpats or Martin(mra), the latter even makes stuff. Good luck and will be following this thread. Terry.

[chrismhall]

I've just rebuilt an early gear box, get as much degreaser as you think you need and double it, and take lots and lots of photos, put every nut and bolt in its own little storage box ( plastic take away boxes are good), and label it, it's not nearly as bad as you think

[wimfournier]

Well done,
I mean, you have 'well done' to dive in the deep; and the brake band is well done too.
When I'm not wrong I've read somewhere that there is some one that 'relines' this kind of brake bands.
I've opened up a automatic Mini box just out of curiousity and have the inner parts lying on a table in my sleeping room.
When I can't sleep I can work on it. My wife and I use seperated bedrooms. She sits behind her sewing machine when she can't sleep. Quite busy at night sometimes.

Go on with the good work!

[joe11]

Hi, Joe Knight here, Ive repaired one so far and modified the box some-what, Ive worked part time as a mechanic,  I want to say Just watch working on Engines and gearboxes if your in a tired state, As it can be the worst time for some of us to complete some hours of the important work without making mistakes.  Some people are better at it when tired but i dont recommend hours of assembly or much at all to be honest.   Its ok to do small chapters of dismantling and working things out but thats about it on a job like this if you are like many of us, an amature.

I have found while reading up on auto box rebuilding a few tips which i want to share with you at this point. 

Ive read somewhere to get a bit more grip on the drum surfaces you can give them a polish up with some wet n dry  220 grit  or finer sand paper lubed with wd40 or similar.
just on where the brake bands work, basic polishing method can be done like on the journals on a  crank, 

While your there its a good idea to de-edge the sharp edges around the top pressure plates in both clutch drums as both are prone to breaking in 1275 boxes and i suspect due to the sharp edges left from manufacturing.
Ive seen them in a couple of 1275 gearboxes  professionally de-edged, and this can be replicated by  using a wire wheel in a drill, Its done on the inner castle gear edge as well.  Some of the plain edges can be done by hand or similar fashion.
I would check all steels on a flat surface for bowing. or put them together but watch out as they can give false reading if both are bowed, Ive seen reconditioned ones surface ground to make them completely flat as reconditioning process.
There must be a tolerance allowed but i dont know what that is,  Most are very slightly bowed and it is soon flattened when the oil loading is on them, But i do wonder if too much bowing has an effect on timing of the clutch slip and a promotion for flare in some cases,  as once slip occurs its difficult to stop it.
The thickest most  top steel plates in both clutch drums  flex when oil pressure is applied, so over many cycles if they are a bit more bowed they will suffer more flexing and i think this may shorten the cast Top pressure plates life in a high mileage box if they have the sharp edges around them.
The thinner plates are not cast and they can flex in use and not suffer the same cracking problem.

[pebbles]

Any idea what this is and where it goes?



It fell out of the valve block (I think) but I have no idea where it goes for sure.

Help!

[limby2000]

Yes its fallen out of the valve block when you split it.

[limby2000]

[limby2000]

Hope that helps, tbh you was a bit brave tackling a breakdown without having a back up of literature.

[pebbles]

Thanks for that. That's a right relief.
Much abliged.

As for fear... I'm a old fashioned C&G trained mechanical engineer (a machinist) that has had a long career (still going, still learning) spread over many subie firms manufacturing stuff from RR airo, Dowty, Westlands, back in the old days thru toolmaking then vacuum chamber work now back to pump manufacturers. The whole saga has left me with a knowledge of the parts making assemblies and therefore a disregard for paperwork due to the (irrational) confidence to attack anything and everything.
Of course something's a Dad can't mend but that don't stop me trying.
When all else fails the forum is a wonderful ressorce and help to the over confident with a mountain to climb.
Thanks for the leg up.

[firept]

My dad always used to say that if man made it then man can repair it, and I have used that philosophy  (not always successfully though ).
A friend of mine who is Jordanian had his old Mercedes car repaired by his brother when in Jordan. when my friend collected his car he noticed that there was a box with nuts, screws etc in it . He asked what they were for and the reply was 'Oh its European they always add extra screws etc that are not needed!' 

Best of luck 

[limby2000]

Dads always know!, i agree ,sometime,s reverse engineering is the best way to learn, even if it means getting left with loads of nuts and bolt left over,lol.

[pebbles]

I was told a similar quote always told to me by a wise old boss (Tony) and it was always when I looked old fashioned at him when he asked me to do something nearly impossible...'what man has made man can make again'
Another boss said (about German 30's racing car engines) that we have now got better machines than they had in their day and "we" (me) can make it again. Referring to amazingly well made parts of Auto Unions (Silver Arrows) we had to replace.
It's all in the mind.
However...
Limby2000 if you have more book led info the gearbox I would be mich abliged. That is how to set the nut length on the selector bar in the darkest corner of the box? I have withdrawn it without working out the method of its replacement. Silly me; Again! It's the one with the plate fixing (with the hex hole etc.) any ideas?
Also, what is the book you have to refer to? Is there a PDF somewhere?
Thsnks for all your replies peeps, it's a real help.

[firept]

Hi Look in the "How To" section on the Home page, lots of downloads there or have a look at the sites below.
I managed to get hold of a Austin Rover genuine Austin Mini Manual for 1976 onwards at a auto jumble for £5....very useful.

www.austinamericausa.com/
www.austinmemories.com/styled-105/index.html
www.youtube.com/watch?v=ieraaVfUs4Q&feature=youtu.be&t=7

[limby2000]

Hi pebbles, do you mean the selector rod that goes through the gearbox, or the cable nut adjustment?, ive got various books/literature your welcome to borrow at return postage cost to you, although some is availiable on here. Hows your rebuild going?.

[pebbles]

My state of play is 'quiet' at them.
Because the other mini, the manual, is now the biggest worry I have a different priority order now.
The manual gearbox is failing and this is now the main concern so that I can give myself more time to dither and chip away at the Auto box. So as you can imaging I will be lifting another engine and with luck getting that up to speed and back on the road first.

As for the Auto box project; I am stumped by the immense cost of the resurrection care pack for it. The brake bands seem to be the only visibly worn part but foresee that if they are worn the clutch plate will be of a similar wornitude. This cost has made me rethink the auto manual balance. I want to keep it Auto in my heart of hearts.

Thanks Limby for the offer of literature, you're a star. I will take you up on that if necessary. I have just purchased an AD015 manual which may help. But will look out for more if I knew what to look out for. Is there a 'best' A+ auto gearbox manual/service sheet?

Thanks for the reply :-)

[pebbles]

Oct 6, 2017 20:24:24 GMT limby2000 said:

Hi pebbles, do you mean the selector rod that goes through the gearbox, or the cable nut adjustment?, ive got various books/literature your welcome to borrow at return postage cost to you, although some is availiable on here. Hows your rebuild going?.

I forgot to reply; It is the rod going thru the gearbox behind the manifold to the corner on the RHS (looking thru the large front inspection plate hole) 
It has a shim-steel folded plate orienting it with a hexagon hole.
Sorry I'm no good with proper names for things.

[limby2000]

I have several, most mainstream manual,s only broach on automatic,s saying "seek professionap help", The best of mine is the Leyland mini manual No AK4935 (9th edition) or AK4886 which is an Austin 1100 automtic workshop manual supplement (very rare). There is a book called The Foulis AP automatic overhaul manual, ive not seen this book book ,and i have tried to get it, but unless your really lucky with a random ebay find, there the thick end of 90 quid,..The box to get is from about 1992 onward,s as they have better component,s. The bands and the plates tend to be the main wear parts,although you will want to be changing all "o" rings whilst dismantled. I know there,s a member called Albannach (spelling might be wrong), who has a fully rebuilt autobox sitting on his shelf, he imports mini,s back from japan , he had it a while back, worth a try. Bought a few bits from him,nice bloke, up in scotland though.May be a cheaper worthwhile option. As for the rod, it screws all the way in, the bit that adjust,s is for the park lock claw which grabs the forward cluch drum. I agree the price for parts is immense with only jpats and Martin (mra) your only option,s. Parts do come up on ebay but are gold dust. Sounds like you come from an engineering background so should be a piece of cake for you.

[hennasxi]

Are all the gearboxes from 1992 until 2000 the same?  I am contemplating buying a cheap write off 1993 car which has a good AP2 in it just for the gearbox, but my car is a Jap spec 1999 built car, so not 100% sure its the same gearbox wise - the engine is certainly different.

[limby2000]

As far as i know, from 92 onwards should all be the same. If your after a box, There,s a member on here called Albanach, although i may have spelt his name wrong. He imports Jap mini,s back to the uk and i know he did have a fully reconditioned auto box sitting on the shelf in his workshop in Scotland. Drop him a line he may still have it.

[clarko]

Hi Pebbles,
I have a similar “If somebody else can do it, then I can” attitude! My 1978 Clubman Estate Auto Gearbox did a similar thing, I ended up getting a low mileage replacement for mine, touch wood, it’s never missed a beat since, a nice engine/Gearbox. I also stripped my Gearbox that I removed, picturing, labelling and boxing everything as I went along, so hopefully it will go back together!! This is maybe a question for Limby2000, but I work in a shipyard and get various clutch bands re-lined with Ferrodo, would this be ok to re-line the mini clutch bands? I think previously you’ve said they are paper lined? Do you think this would be long term alternative? Thanks John

[limby2000]

Hi not sure about the band re-lining, i know jpats have old bands relined too, although not too sure on the materials, brake materials may be too course and cut into the bevel gear drums. I know there are firms that specialise in motorcycle (wet) clutch relining but have not had to. I think bands are about 50 quid uk exchange from jpats.

[pebbles]

Oct 6, 2017 20:24:24 GMT limby2000 said:

Hi pebbles, do you mean the selector rod that goes through the gearbox, or the cable nut adjustment?, ive got various books/literature your welcome to borrow at return postage cost to you, although some is availiable on here. Hows your rebuild going?.

If you're still out there limby2000 in reply to your question How's the rebuild going? it is going well but in a very different direction...

While I mulled over what to do I had to get the car back on the road. Thus I decided to abandon any quick automatic G/box fix and borrow a mates 1275 manual for a replacement then figure out what to do about the Auto.

That was then. Now I have made my mind up to get over myself and my over-confidence (thinking I could handle an Auto refurb) and stay with the Manual. 

The only issue is getting rid of the Auto gearbox parts now surplus to requirements.

Sorry for the appalling delay in this reply but thanks to all the suggestions and help given.