Converting to rear discs on a 110

[western]

90/110 have always had 4 pot calipers up front with drum brakes or 2 pot rear calipers at the back, IIRC RRC has 4 pot from the first one too, as does Discovery.

[bluehaze]

OK - thanks

Are all 110 rear calipers the same with the exception of ABS? As they are differing prices on fleabay.

[Retroanaconda]

I know nothing of ABS and it's variations, but I doubt it affected the calipers.

I think in later Td5 models they increased the rear pad thickness to address premature wear concerns - so I would expect the calipers to get wider as a result of that. But in terms of fitment it wouldn't affect it I don't think, so long as you order the earlier/later pads as appropriate for the calipers you end up with.

[western]

I don't know about the latest Defenders with ABS, but AFAIK from caliper pictures on the net they look the same, still single fluid line in.

[UdderlyOffroad]

I couldn't make post 1991 Disco calipers fit - good job they were free to collector really...bought 110 rears from Bearmach in the end. Sticking with 'stock' setup has to be the easiest way to go.

[western]

looking at the part numbers 2 of the Disco 1 rear caliper part numbers are the same as mine [correct 110 rear calipers] there's 8 numbers for D 1 rear calipers, obviously 4 per side as LH & RH have different numbers,some of the numbers match 90 rear calipers too

[Aragorn]

Western: I cant really tell from the pic, but are those hubs the later style with thin drive flanges? or the earlier style with thick flanges?

If they're the earlier style, you'll presumably need to fit a spacer to the caliper bracket?

[western]

they have their matching thick drive members on, same as my 110 has from new, the spacer I can make with help of a friend, I'm sure if I take the brackets with me, 2 spacers can be made fairly quickly.

I've got the mudshield & brackets to fit to.

made enquires with a localish general engineering co, to make 2 spacers for me, dependent on their price, I may get more made to help others out.

Edited March 26, 2013 by western

[western]

more info about my spacers, I'm having a pair laser or waterjet cut, the price is I think extremely good at £18.61 inc VAT,

if any body needs a set to convert a pre 300tdi 110 drum braked rear axle to rear disc & need a set of spacers send me a PM.

[Somethingwitty]

Not quite a thread hijack but... I'm a little way ahead of some of you - yet behind in one aspect!

I've been running a rear disc conversion on my 110 since 2008 with few problems (save for eating pads - I think inboard pads suffer from increased wear due lack of mud guards). However, I recently changed discs (due to the aforementioned pad eating) and noted that the inner races of the outer bearings do not fully bear on the stub axle bearing lands - i.e. the reduced stub axle diameter for the threaded / plain portion extends to nearly half the depth of the inner race! I roughly remember noting this as unsat some time ago but time was short so I've just kept an eye on it since.

I bring this up now due to the significant (!) play found which required some significant 'nipping up' of the adjusting nut. The conversion uses (I am pretty sure) FRC6139 hubs (ie early 110 front) and the original spec Salisbury drum (FRC8540) stub axles (I am pretty sure - replaced them at some point...) Although not likely to be pertinent I retained the old early halfshafts and flange and used a 6mm spacer for the calipers.

The hubs are pretty impossible to confuse with FTC942 (no 'slash' on studs, distinctly different casting on rear face - like Western's photos on Post #93); I also think If I'd inadvertantly fitted FTC1740 (300Tdi) stubs then I'd have been unable to get the locknut on through lack of stub like UdderlyOffRoad's blue hub on post #58 (but I don't know this for sure).

I am about to order another stub (FRC8540) on the assumption that I've somehow got the wrong one fitted. However, can anyone shed any light on my predicament please? Is the early 110 hub easy to confuse with another, say RR, with even wider bearing spacer? Is there a similar stub axle to the FRC8540?

EDIT: - Or does everyone else run a half-supported outer bearing?!

Ralph, I am glad someone else is nearly as slow as me at getting jobs done!

[western]

this thread about stub axles for this conversion might help http://forums.lr4x4.com/index.php?showtopic=59339&hl= IIRC the 300tdi stub/hub bearings are closer together than our anceint drum braked stub/hub bearings.

mine are/will be 110 fronts on the existing fitted stub axles.

AFAIK & can find the FRC8540 are only used on 110/127/130 vehicles.

[Somethingwitty]

Hmmmm.... the plot thickens!

Thanks for the link Ralph, had a look and nothing conclusive but useful nonetheless - I'd always assumed all flanges were equal save for thickness...

Looking back through Diesel_Jim's conversion LINK I found that, as far as I can see, he also has the same issue. I've tried to attach a close up photo but it may not work - however the image in question can be found by...

Scroll down to the photo of the inboard face of the disc / hub combo (off axle).

Beneath this is a sequence of three phots of the hub / stub / bearing, lock washer and nuts. The first of those three best illustrates the issue - a partially unsupported inner race. (admittedly I do not know if his hub / bearing was fully home on the stub).

Have you encountered a similar situation yet? I'd get a phot of mine but it's bloody cold and I've just put it back together!

[western]

Haven't begun my conversion yet,

I know that axle in the linked thread was fitted to V8Freaks red 110, which has now moved on to another owner, I believe there was no problem with the bearings,

[Somethingwitty]

You haven't? Further support for my incredibly slow progress on projects :-)

Thanks anyway, I've nipped it up, will give it some abuse, investigate and report back.

[Snagger]

FAO Somethingwitty - that sounds peculiar and worrisome. I did the conversion on a 110 Salisbury axle, and Gremlin did it on a 109 Salisbury axle. In both cases, the outboard bearing needed spacer washers for the nuts to get the correct pre-load, and these on the 109 axle needed to be thicker than original. I tried using 109 spacer washers on my 109 axle and had to bevel the inner edges to get them to fit over the ends of the smooth section of stub axle, as did Grem, quite the opposite of your problem. I later found the original 110 spacer washers with the integrated rubber seals, and that made life easier. I suspect your bearing races might not be fitted correctly in the hubs. You haven't got two outer races on the outboard side of the hubs, have you? It would result in roughly the bearing spacing you describe...

[rekab69]

That axle is still working very well under my truck !!!

Neil

Neil, your old axle is still going strong under my truck, converted to disc too.. Dave.

[western]

picked up my spacers today, nicely made & cut, just need to open up the bolt holes a bit to allow easier bolt alignment I should have asked for 11 or 12mm bolt holes to be done, but not to worry a quick run through with the pillar drill at work will sort them. hoping to do the fit soon.

[Adam001]

Sounds good.

Stupid thing is, I started this post, have done the conversion...but I don't remember what parts I ended up using! haha

[bluehaze]

Quickly strip them down!!!!!!!!!!!

[western]

Made a start on converting the rear drum brakes to disc, now I have [or thought] all the parts required, started on the left rear, stripping off the old drum & hub I found the seal was giving up, lots of black greasey oil & brake dust inside the drum, next was the brake pipe which end up being twisted off once the end fitting unsecrewed from the brake cylinder,

new disc & hub went on OK, but had to use the front hub tag spacer & a D shaped hole lock washer between the inner adjuster nut & the outer bearing just to eliminate unwanted play, another D lock washers & outer nut & the hub is safely secure.

getting the new 6mm spacer [measured & confirmed as 6mm thick] & caliper bracket in place & the mudshield went fairly well, I need to either cut the bolt threads down or get some 50mmm long bolts, the 55mm long bolts stick out a bit to much but not enough to fit a full nyloc nut on.

offered up the new caliper & got the 2 bolts in place & nipped up,

then found the caliper inner face [inboard pad/piston area] was touching the disc so tight I couldn't rotate the disc,

a bit if trial with various washers, I ended up with the need for a 5mm washers/spacers at each caliper bolt location as well as the 6mm thick caliper bracket spacers I had made, so at the moment I'm not overly happy

so I don't know how Diesel JIm & others have got past this point, as in the various threads there is no mention of this little hiccup, can't do anymore until I can get either 4 x 5mm M12 washers/spacers or 8 x 2.5mm washers or similar to make the caliper sit in the correct place as in the 2 photo's

Edited May 6, 2013 by western

[Snagger]

I found two alignment problems, both mentioned already, but for clarification:

1) The 90/110 front hubs are slightly wider than the Salisbury drum braked hubs, so you can't use the thick spacer washer from the Salisbury under its bearing nuts. I used Discovery spacer washers to press the wheel bearings back against the stub axle, with the inner edge bevelled with a file to allow it sit over the beginning of the smooth section of the stub axle - if you don't bevel the washer, it won't press against the bearings and you'll have way too much end float;

2) The position of the calliper relative to the disc is way off, needing either spacing to move the calliper and its bracket inboard, or milling of the bracket to move them outboard, depending on the choice of calliper and disc. I used 110 rear/RRC and Discovery front discs, with Discovery/RRC rear callipers. It's not an ideal set up as the disc is a bit thick and has a larger radius, so clearance is tight in the calliper, and when the rim of the disc gets rusty, it'll have to be cleaned up to maintain that calliper clearance, but it clears at the moment. I used a 6 or 8mm shim on the mounting brackets. With Defender callipers, the offset will probably be much thicker - the thinner hubs would put the discs further inboard. That is where Western has had to use washers in addition to his spacers.

[Aragorn]

Wouldnt it be better to have a thicker caliper bracket spacer made? Rather than spacing both the bracket and the caliper?

[Snagger]

Wouldnt it be better to have a thicker caliper bracket spacer made? Rather than spacing both the bracket and the caliper?

It would, but I suspect Western may have used the dimensions used by Gremlin and me, who both used the same solution, and not realised the different dimensions of the Defender callipers until final fitting. You'd have to ask him, though. I did use washers during the initial build up to see what would work, but once I had worked out the plan, I went for a rigid spacer as I think it will be less likely to bend the mounting bolts. Washers should be OK, but in Western's position, I'd probably make up new thicker shims or a second shim to add to the first, which would work just fine.

[Snagger]

Hmmmm.... the plot thickens!

Thanks for the link Ralph, had a look and nothing conclusive but useful nonetheless - I'd always assumed all flanges were equal save for thickness...

Looking back through Diesel_Jim's conversion LINK I found that, as far as I can see, he also has the same issue. I've tried to attach a close up photo but it may not work - however the image in question can be found by...

Scroll down to the photo of the inboard face of the disc / hub combo (off axle).

Beneath this is a sequence of three phots of the hub / stub / bearing, lock washer and nuts. The first of those three best illustrates the issue - a partially unsupported inner race. (admittedly I do not know if his hub / bearing was fully home on the stub).

Have you encountered a similar situation yet? I'd get a phot of mine but it's bloody cold and I've just put it back together!

I had a look at those photos, and it looks to me like he used 300 stub axles with the 110 hubs. This means the shorter stub axle is not seating the outer race on the smooth section of stub, so is not supported properly, and the whole lot is only shown as secured by one nut, not the two required. I don't think that's a safe installation if the photos are showing the hub fully pressed on.

As I said before, and as Grem did on his, you retain the original stub axles and shafts, all you change is the hubs and the spacer washer that goes behind the first hub nut, replacing the original very thick washer with incorporated rubber seals used on the 110 axle originally with a Discovery equivalent, filled a little to press up over the nose of the smooth section of the stub against the wheel bearings.

[western]

It would, but I suspect Western may have used the dimensions used by Gremlin and me, who both used the same solution, and not realised the different dimensions of the Defender callipers until final fitting. You'd have to ask him, though. I did use washers during the initial build up to see what would work, but once I had worked out the plan, I went for a rigid spacer as I think it will be less likely to bend the mounting bolts. Washers should be OK, but in Western's position, I'd probably make up new thicker shims or a second shim to add to the first, which would work just fine.

Correct, I wasn't aware of the different diemensions as no-one had mentioned these before, ideally I would use new thicker caliper spacers, I can get some made but don't know how long it would take & the place that made the last set is 6 miles away & my 110 is my only vehicle, I'm on holiday this week, so need a quick solution, hence using thick washers, [got to get more today]

the stubs are the existing salisbury drum braked stubs, not from another vehicle, I know this becuase my 110 has been with me since 1993.

as to the bearing/hub fit on mine, I used the inner outer nuts, the key spacer as in the front hub fit & a D hole lock washer against the spacer & another D lock washer between the 2 nuts, hub is on & rotates easily without any excess in/out movement.

got to go out anyway today [by bus] will also ring the place that made my spacers & find out how quick they can cut a new set of thicker spacers.

spoken to my spacer makers, they are going to make me another set 10mm thick with 12mm bolt holes, but it'll be 7 days before I get them, so I need to use washers in the meantime.I'll report back later on progress.

Edited July 10, 2015 by western