9 replies to this topic

[danie garry]

hi all, just getting round to fitting the 8.4" to 7.5" brake conversion to the car and iv hit a bit of a problem.

when im fitting the disc and drive flange to the hub its binding and locking up on the hub, even with the hub nut only hand tight! has there been any discs where the bore is too small to fit over the hubs or anything or am i being a bit simple and missing something?

also the tapered washer for the hub nut is sitting proud against the drive flange? im guessing it will tighten in when the nut is torqued up?

cheers

 

Edited by danie garry, 23 April 2014 - 10:12 AM.

[Dan]

Late 8.4" hub uprights are not machined exactly the same as they were for 7.5" discs, despite being made from the same casting. The nose section where the outer oil seal fits was originally wasted down very thin in a step, allowing more space inside the disc bell when the 7.5" disc is fitted. When fitting 7.5" discs to a later hub you can get this problem but it's a result of stacking tolerances so there isn't a hard and fast rule about what will fit and what won't. Simply put some discs will clear some hubs and others won't. You can either swap discs and hope that the new ones have more clearance, or take the hubs to have the outside taken down on a lathe to match the earlier design,

[RawlinsGTR]

I had the same issue with my conversion.

 

I took them back to minispares who measured them with some calipers against another pair, and they were both the same, so it was obviously my hubs.

 

What I did was file down the outside of the hubs to get all the old rust and dirt off, which mostly solved the problem, but there was still some binding, so I just had to file them down a little more where it was rubbing.

 

So you could try that first before you do anything drastic.

 

As for the tapered washer, mine uses the split ones (FAM9270A) :

 

 

Is your mini a pre 1984? If not then I'd be assuming that you should have the split tapered washers to, which fit flush.

 

Simon

Edited by Dog., 23 April 2014 - 11:48 AM.

[geoff-d]

I had the same problem two weeks ago on the offside only. I cleaned all the rusty crusty bits off the outside of the hub using a wirebrush on a grinder worked problem fixed . Have used them for over 1000mls no problems.

[The Principal]

I have had this problem before, make sure you have the correct drive flange before making any costly mistakes with a grinder. The confusuion comes with the standard Disc Drive flange and the Metro NAM6450F.

[danie garry]

think its going to take a bit of hub work, its binding with the nut finger tight! fairly sure the right flanges came in the kit so il get to work on the bearings now and get the hub trimmed down! was thinkin as much with the washer, cheers

cheers lads, onwards n upwards!

[RawlinsGTR]

Mine started to bind finger tight to, by the time it was nearly tightened the disc wouldn't rotate at all.

 

The place it binded the most was on the edge of the step on the circumference hub, so that's where I focused my attention. Give it a try before getting them trimmed down, might save you a lot of time and money!

Simon

[danie garry]

Mine started to bind finger tight to, by the time it was nearly tightened the disc wouldn't rotate at all.

 

The place it binded the most was on the edge of the step on the circumference hub, so that's where I focused my attention. Give it a try before getting them trimmed down, might save you a lot of time and money!

Simon

 

letting the hubs soak so il b able to see what needs grinding off, cheers for the heads up!

annoying when all i wanted to do was change discs n calipers! now escalated to hub,  bearings, ball joints and cv's! 

[The Principal]

out of curiosity where is binding? is it the bearing carrier (round hub part) or on the steering arm? or somewhere else

[danie garry]

out of curiosity where is binding? is it the bearing carrier (round hub part) or on the steering arm? or somewhere else

 

on the bearing carrier, as if the hub is too big or the bore on the disc is too small!

you can see in the pic in the first post where its catching