10 replies to this topic

[The Otter]

Hi guys

Swapping over gearboxes at the moment and I need to know what to check for when looking at a second hand gearbox. I've sourced one from a pre A+ 1098 engine, but I want to be as sure as possible that it's good before I put it in the car and find it's scrap. So, what I was wondering is what is there to look for in terms of wear in a gearbox, apart from the obvious (teeth missing/damaged, etc). It's been full of oil whilst it's been in storage (still attached to the engine) and only drained this morning to get it off the block.

I took a few pictures to get some idea of whether the box is sensibly useable or not. I don't have any experience at all with gearboxes, and I don't know exactly what some bits are called, so you may have to give a little explanation if something specific looks bad... also, please forgive/correct me if I give some things the wrong names

I think this is the first gear baulk ring which looks quite worn:





I think these are the synchro/dog teeth on one of the gears, you can see a chunk missing from one of the teeth:



Some general views:





I particularly need to know whether the diff is okay, as that's the reason why I'm switching boxes - there's a terrible whining/whirring noise that's started in my car and we 'think' it's the diff. The driver's side pot joint on my current gearbox moves in and out of the diff casing by at least 5 or 6mm, and these pot joints don't move in and out at all, so I'm assuming that's something gone/excessively worn in the diff - hence the whirring noise.

Here's a couple of pictures of the diff internals, if there's anything obvious to tell from these...



You can just about make out that there's a small chunk missing from one of the teeth in this shot.



Also, I've been told that swapping between A and A+ boxes is a straight swap with no changes required - is this true? The box (pre A+) will be going on my A+ 998.

If there's anything obvious I can do to check for play/wear in any areas, then please let me know so I can do any checks tomorrow before we get further through engine out/gearbox swap process. I must stress that I don't expect this 'box to be perfect, it just needs to work and drive me around for another 4 months or so at least, so if anything is seriously on it's way out then I obviously don't want to use it.

Any advice/comments will be appreciated.

Many thanks

Sven

[OfMini&Men]

No difference I got a Pre a+ on a A+ engine just made sure my drop gear where a set.

[Guess-Works.com]

From the condition of the lug on the 1st baulkring, which along with the damage to the dog teeth, I suspect that this gearbox has been used HARD. The damage is consistent with it being dropped into 1st at speed, the lugs on the baulkrings are heat hardened that those are absolutely mullered, in fact I think probably the worst I've seen in a long time, and that includes 'grasser boxes which really do see some aggressive driving.

Likewise 2nd gear is showing signs of wear on the dog teeth, the chip is not so bad it's the fact that they should be pointed on the front, and most have been worn round.

The diff pin is a very old one with the cross hatching to allow oil into where the planet gear runs, this will need replacing...

Finally, yes you can put an A series box on an A+ engine, that's not a problem, but you need to get the right transfer gears, in this case you will need an A series idler and primary gear and also an A series transfer case or conversion bearing for your A+ case.

Long and short, probably cheaper to get your A+ gearbox reconditioned.

[jaydee]

This box has seen better days, you'd need to inspect the bearings too.
I think you can swap the A+ box with the older A series box as long as you're fitting the complete box (you cant mix gears, bearings and shafts)

[The Otter]

Cheers for the replies guys, particularly Guessworks. I'm doing the swap at a mini specialist that has a few engines lying around, he's letting us have a gearbox from one of them and this just happened to be the first one we pulled out. We'll have to see if there are any better engines/'boxes in his shed! At least I'll have a better idea of what to look out for on the others, hopefully there's a good enough one in there somewhere.

I would get mine refurbished, but I really am on a tight budget at the moment and this is the cheapest and quickest option for me with the car being a daily driver.

Sven

[Guess-Works.com]

1. don't put a gearbox on the bottom of your engine which has been open to the elements or at risk of things being dropped into it
2. don't put an unknown gearbox on your engine, unless your 'specialist' is ready to fix/replace it without charge if it does not work.
3. don't jet/steam wash out a gearbox and then hope it'll be ok, the shafts and bearings will probably go rusty before you put the oil in.

[The Otter]

Cheers for the concern Guessworks,

1. Don't worry, all the gearboxes I could use are still attached to the rest of the engines, so they'd have been well protected and hopefully submersed in oil whilst in storage like this one was.

2. Me and a mate are doing all the work, we're only at the specialist to borrow his tools and workspace (he's a very kind chap), and with a bit of advice like this from you I'm confident enough in myself to decide whether it's worth the risk or not to use a gearbox. I'm doing a Motorsport Engineering degree at uni at the moment, so I'll need to get experience of this sort of stuff sooner or later - no point knowing how to design a gearbox if I don't know how they work!

3. I would never dream of doing anything like that, I'd only wipe out any nasty sludge with a rag and be very careful not to get any fibres caught on the casing/gears.

Any more advice would be most welcome

[jaydee]

2. Me and a mate are doing all the work, we're only at the specialist to borrow his tools and workspace (he's a very kind chap), and with a bit of advice like this from you I'm confident enough in myself to decide whether it's worth the risk or not to use a gearbox. I'm doing a Motorsport Engineering degree at uni at the moment, so I'll need to get experience of this sort of stuff sooner or later - no point knowing how to design a gearbox if I don't know how they work!

So this would be a good chance to rebuild your own engine and box and learn a lot things. Plenty of helpfull experts on here that can give you advice.

[The Otter]

2. Me and a mate are doing all the work, we're only at the specialist to borrow his tools and workspace (he's a very kind chap), and with a bit of advice like this from you I'm confident enough in myself to decide whether it's worth the risk or not to use a gearbox. I'm doing a Motorsport Engineering degree at uni at the moment, so I'll need to get experience of this sort of stuff sooner or later - no point knowing how to design a gearbox if I don't know how they work!

So this would be a good chance to rebuild your own engine and box and learn a lot things. Plenty of helpfull experts on here that can give you advice.

I would love to right now, but the car is a daily driver, I need it back on the road as soon as possible and (at the moment) as cheaply as possible.

Ironically, I only bought a 1275 engine a week ago, with plans to do a light re-build over easter and do this engine out stuff then at my leisure! The plan was to then get the 998 out and learn all about re-building it fully in the summer whilst I use the 1275 to run around in. That's still the plan, so whatever 'box goes in now will only be a temporary fix until then.

I'm sure some of you will understand this is a sensible option for me right now, I like doing things as properly as possible, but at least I was sensible enough to check on here first as to whether that knackered box was any good or not.

[Badboytunes]

Listen to Guessworks. This guy knows his stuff !

[cal844]

Listen to Guessworks. This guy knows his stuff !

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