disassembled gearbox(part assesment)
Turbo Mini Forums

hi guys..

just got my gear box disassembled, only thing left is the selector forks etc...cant get the roll pin out.::( for my first try it did not go to bad. lost a couple of springs and balls though:S

any way i took some pictures and was hoping you guys could help me deciding what needs to be replaced.

i check all the gears and all are fine, no marks, no pieces missing look pretty dam good to me.

the lay shaft and main shaft do have some marks, which seem fine to me, but what do you guys think?







lay shaft





also two of the needle bearings look like this, split in the middle? they dont seem broken but i found it strange that they were split and the other one is a complete circle. is this right?



also, dump question but which of these synchro hubs is for 1/2 gear and which is for 3/4, i assume the larger one(the one on the right) is for 3/4 gear. is this correct?





thanks;D

Edited by c2_mad on 4th Aug, 2011.

yes they appear to be all servisable and in decent fettle .............. just shows how regular oil and filter changes work ........i have stripped many a gearbox to find out all the lots goosed through tight previouse skimpy owners of the engine in the past

Edited by BENROSS on 4th Aug, 2011.

Thanks for the reply Mr benross, thats exactly what i wanted to hear

another quick question are these the two bearings i need for the main shaft?:
http://www.minispares.com/Product.aspx?ty=...id=35662&title=

and

http://www.minispares.com/Product.aspx?ty=...id=34555&title=

the reason i ask is becouse i see they have one specific for the turbo, but i thought all 1275 gearboxes were the same.

here is the link for the turbo one.

http://www.minispares.com/Product.aspx?ty=...id=32830&title=

ps: its an a+ box

cheers

There are actually three bearings - two large ones in the main casing and the smaller one that supports the overhanging end of the input shaft and locates in the transfer housing. It's the one you would have taken off first (belongs on the very end of the shaft, right hand side of your third photo).

It is this one (only) that is a larger size for the turbo box (or more technically, the transfer housing that belongs with a turbo box).

The two bigger ones inside the main casing are the same for any 4 synchro boxes.

The bearing you missed is this one

http://www.minispares.com/Product.aspx?ty=...id=37976&title=

Schrödinger's cat - so which one am I ???

now im confused...:S

there is the double roller bearing, which sits in the middle of the gearbox, then there is the one in the link you showed me. thats all i took out form the geabox. 2 of these "big bearings one from each side...

am I missing something?

i think i have figuered it out... the one in your link Rod S, is that the one that would be plastic with small rollers? that sits on the very to tip of picture 3, where the groove is?

Yes, if you intend to attach it to an engine.....

In your third photo is the bit of the mainshaft normally called the first (or 1st) motion shaft.

Once it's back in the gearbox with the big bearing I linked, the input (bottom drop) gear goes on, then the nut/locktab then, on that last remaining bit of plain shaft belongs the smaller "nose" or "support" bearing. You can see the circlip groove for holding it on in your photo.

What you actually fit is just the inner race and rollers of said bearing, the outer race is fitted to the transfer housing - have a look at your transfer housing and you will most likely see the old outer race of the old bearing.

I'll see if I've got a photo somewhere...

Schrödinger's cat - so which one am I ???

The one I added the link for is the one in the gearbox... the one (and the turbo alternative) that you linked to are the small one, plastic cage (normally) and small rollers.

The photos in Minispares catalogue are deceptive over the sizes.

Schrödinger's cat - so which one am I ???

Make sure you try your baulk rings on the gears. they should slide up the gears and lock around 1mm from the face/teath on the gear. As a minimum you should be able to see a gap.

Try them on different gears and see which ones give the best gaps on each gear when reassembling.

i see Rod

so let me see if i have got this now(links to what i need)

http://www.minispares.com/Product.aspx?ty=...id=35662&title=

http://www.minispares.com/Product.aspx?ty=...id=37976&title=

http://www.minispares.com/Product.aspx?ty=...id=32830&title=

is it worth getting the "turbo" one? or will the normal one be up to the job?

correct?

thanks for the tip apbellamy, as for the baulk rings i was going to get these
http://www.minispares.com/Product.aspx?ty=...id=37304&title=

better to use original Rover/BL baulk rings where possible. The reproduction ones vary in quality

Edited by apbellamy on 5th Aug, 2011.

In the order you have now listed the links it is the correct three BUT the last only for the turbo transfer housing.

I'm afraid it isn't a case of whether the turbo support bearing is worth it, it's whether it will physically fit. They are both the same internal diameter so both fit on the end of the shaft but the outer race of the turbo one is larger so only fits into the turbo transfer housing.

You basically need to know which transfer housing you have (was the whole assembly a genuine original Metro turbo one?) and buy the bearing that fits it.

Schrödinger's cat - so which one am I ???

i just noticed that the price is for one baulk ring....:S:S:S this gearbox business is dam expensive.

i bought it as a turbo unit, and every part so far has proved this to be the case. so i would imagine it is a turbo transfer housing.

will measure it to make sure as it says on the mini spares site its 42.98mm o/d

Edited by c2_mad on 5th Aug, 2011.

Also very carefully check all the little 'dog teeth' on the gears and on the synchro hubs! They'r often worn out, especially on 2nd gear... Should look like this:




And NOT like this, as they do so often...




And that's where it gets expensive when you need new gears... :(

Ignore this post if you allready did & know - it's just too important to not mention it :)

The last gearbox I build I used 3 non-genuine baulk rings (MS) on 1st, 3rd & 4th and a genuine one on 2nd gear. With 4 gen rings I had trouble in the past (gearbox binding and not spinning freely)... Though I'm yet not 100% what the problem was. Either they are concentric or too smal in the inner dia. In my current gearbox I use 4 good used rings - no troubles either. 3rd and 4th are often still very good and don't need replacing anyway....

[X] nail here for new monitor

hi asphalt have checked the dog teath, all seems ok in that departement. thanks for the heads up anyway

as for the baulk rings, would it be ok to use the old ones then? all the gears went in fine with no crunching etc so i assume that they are fine... or would it be best to get new ones for peice of mind?

Check the baulk rings as I described, if they are OK re-use them. No point spending money you don't need to

Schrödinger's cat - so which one am I ???

well go out and do so in a moment thanks for all the tips

I would be lost with out this forum

Edited by c2_mad on 5th Aug, 2011.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

just confirmed i have a turbo transfer housing... how important is this bearing, as mine was in pretty good nic. or should i just replace it anyway?

apbellamy, any chance you have a pic of what you mean as i tried to check the clearance you were talking about but couldnt figure it out. sorry:S first gearbox rebuild so not 100% sure how everything works

benny thats with straght cut items etc.. right? the day you bought that stuff must have been painfull..lol

The gap between the baulk ring and the gear should at least be 1mm. If the ring travells all the way up on the cone or the gap issmaller, it should be replaced.



^that one's fooked

Edited by Asphalt on 5th Aug, 2011.

[X] nail here for new monitor

double post...

Edited by Asphalt on 5th Aug, 2011.

[X] nail here for new monitor

Schrödinger's cat - so which one am I ???

thanks for that asphalt will have a look at mine, hopefully they are fine.

Rod, i see what you mean. mine were prety tight as i struggled to get them of the plastic cage. so i think it will go again no problem. will put a big blob of grease for good measure also thanks for the help mate

Edited by c2_mad on 5th Aug, 2011.