So I've got these spare bits...

[Multiphonikks]

Hey folks,

I picked up an entire free transmission at the weekend so have plans to take the free bits and rebuild them.

I'll need a new clutch in the next few thousand miles, but I'm probably going to try and get the gearbox sorted and also fix this U/J problem (and the diff which is getting noisy)


First thing I'm thinking of tackling is the gearbox. Any tips?

Secondly, does anyone know if transmission places would do exchanges on a standard diff to a better ratio one?

[bmcecosse]

By transmission - do you mean gearbox ? Best bet - go get a Haynes - read it, and read it again. Then clean the box thoroughly, drain the oil - and follow the Haynes. Minor box is easy - easier than a Mini !

[Multiphonikks]

The book of lies?

Surely not?!

My book of lies has all the gearbox pages in reverse print. Someone managed to get the printing plates the wrong way around

But yeah... Transmission = full gearbox, propshaft, rear axle,

[bmcecosse]

Yes indeed - HBOL. The very best version for a Mini gearbox strip description is actually the Metro HBOL - I picked one up for £1 at Scout sale - the box is virtually the same as the Minor. As for diff ratios - well a Wolseley 1500 diff sold last week on ebay for £50 I think - just stick with what you have.

[rayofleamington]

First thing I'm thinking of tackling is the gearbox. Any tips?

Yeah - don't do it unless you really have to.
If the box is already noisy in 1st gear then it is often much easier just to find a good gearbox instead. If it jumps out of gear then you really need to know the box design well to find out what to fix (jumping out of gear gearboxes are normally just thrown away)
The minimum you want to do is check for any slop in the bush (plain bearing) where the propshaft fits. If it has more than a miniscule amount of play then this need to be replaced.
This involves removing seal, then pushing out the old bush. The new bush (about a fiver) needs to be pressed (carefully hammered) into place and then reamed to the correct size (sliding fit with the propshaft nose). This isn't a 'standard' reamer size so you need to phone around to find a machine shop with an adjustable reamer and some skill too....
A new rear bush will help prevent any run-out of the prop. This run out makes a lot of vibrations which tends to wreck things. In combination with a new spigot bush for the input shaft to sit in, and some fresh oil, you are going to give the box the best chance of longeivity short of a complete rebuild.

[Multiphonikks]

First thing I'm thinking of tackling is the gearbox. Any tips?

Yeah - don't do it unless you really have to.
If the box is already noisy in 1st gear then it is often much easier just to find a good gearbox instead. If it jumps out of gear then you really need to know the box design well to find out what to fix (jumping out of gear gearboxes are normally just thrown away)
The minimum you want to do is check for any slop in the bush (plain bearing) where the propshaft fits. If it has more than a miniscule amount of play then this need to be replaced.
This involves removing seal, then pushing out the old bush. The new bush (about a fiver) needs to be pressed (carefully hammered) into place and then reamed to the correct size (sliding fit with the propshaft nose). This isn't a 'standard' reamer size so you need to phone around to find a machine shop with an adjustable reamer and some skill too....
A new rear bush will help prevent any run-out of the prop. This run out makes a lot of vibrations which tends to wreck things. In combination with a new spigot bush for the input shaft to sit in, and some fresh oil, you are going to give the box the best chance of longeivity short of a complete rebuild.

See, while I'm no longer a student I am still in that wonderful area which inabits 'employed and paying taxes' and 'savings, what are savings?'

So erm yes... See, gearboxes are expensive. I have a spare one just sitting there looking like it needs opening up and a seeing to. It says "Fix me Nikki, Fix me!"

So while I know it's a tough job I figure that I'll never learn if I don't actually have a go. Besides, I think it'll keep me busy ;)

[Stig]

Go on, have a go. It's not that bad a job really, takes a while and a full set of bearings and synchro rings does cost more than a secondhand box but at least you know everythings sorted.

I did mine a few years ago after it ran low (OK, empty) on oil. You know how it is, you check levels every week to start with and they're always fine, get kinda complacent after a while and then an oil seal starts leaking and you don't notice as the engine spreads a lot of the stuff over the gearbox anyway. Then you think "Hmm, seems to be rather noisy these days", check the gearbox oil, swear, then decide you'd better rebuild it rather than just topping it up. Ho hum.

[bmcecosse]

It's easy - you should have it done by now !

[Multiphonikks]

... nah, we were too busy stripping Kate's 1275 engine ;)