Discovery Rust - Boot, Sills and Wings

FRONT DIFF REBUILD

Yes today I started the job that I was putting off for a bit however, needs must and last week it became apparent that I needed to replace the pinion bearings in the front diff.

WHAT LEAD ME TO THIS? I hear you cry with excitement ish type cries, well I had noticed that the steering was becoming stiff when just off centre but when I was stationary, it seemed fine.

Also as I had just replaced the rear diff, the really loud noise at the rear had disappeared only to allow me to hear the front hum and whine. Well actually I hear a whine from the front most of the time BUT this time I could still hear it even when the misses wasn't sitting in the front seat

Also, yes there is more, I noticed that as I was coming to a halt, there was a discernible rumbling and vibration at the front.

Finally on drawing underneath I noticed the same amount of play in the front flange as I had noticed before in the rear just before the rear went for a burton.

So it was time to whip it out and once I had jumped the misses I went out to play with the car

Firstly I cracked the wheel nuts to the front wheels, jacked up the front and placed axles stands under the axle so the front was secure.



Then I removed the steering bar and the drag link. Both of which are heavy duty but I was surprised to see a bend in the Drag Link.



Wth the steering disconnected and the wheels off and to one side, I set about removing the hubs. If you have more time I would recommend removing the brake calipers and setting them to one side. This way once you have unbolted the swivels from the axle casing you can fully withdraw the half shafts. I on the other hand simply undid the bolts and left the whole assembly in tact.

The six bolts



Nearside removed and secured







Then I went and repeated the process at the offside.

Once both hubs were secured I then removed the diff guard and set about undoing the front propshaft from the drive flange.

He you can see the traces of oil around the flange which has been thrown out and spread about.



The prop shaft was then secured out of the way by tie wrapping it to the clutch slave cylinder bracket



It was now that I noticed that in the last week not only has the gearbox drain plug started to weep, but the front drive flange on the transfer box has started to also.this seems quite bad so today I ordered another bearing and oil seal along with a drain plug washer for the gearbox. Keep tuned for me replacing the bearing on the drive flange.



So time to unbolt the diff (or more accurately the Pinion Housing)

Here you can see the nuts around the perimeter.mthese are all 9/16" and were easily undone as the axle isn't that old. Probably replaced just before I got it.



Once all the bolts were removed, a few minutes manipulating the diff out was all it took and tadaa






As you can see the diff is in really clean condition and despite a fresh oil change there are signs of muddy ness after just a couple of wading sessions.

Here's the inside of the axle casing



Once the bearings arrive I will replace them, taking photos and then put it back together. Fingers crossed it all works as it should.

Stay tuned.......

What a exellent thread!! Thanks for taking the time to take pics whilst working, people forget what a pain in the ass it is, then to upload them ect ect so yer many many thanks, wil be invaluable when I come to do mine!!! All best....clive

You been pushing "lesser" cars out the way with your drag link..?

Cheers discocheese

JonnyP,

Yes mate I have lol. Seriously though I can't honestly remember any tough hits that could have done this. Regardless of what she is built for, I am careful off road so I'm very surprised.

I may change my mind about a steering guard arrangement now.

So this morning ally bearings and seals arrived. Now there was a bit of confusion on my part and a little delay on theirs but I must say that I was really pleased with what I received.

I used BRITISH PARTS UK (Jaguar Parts | Land Rover & Range Rover Parts | British Parts UK) and not only are they the most reasonably priced company out there, but they are excellent with customer service.

When I received my package, as a thank you and an apology for a little delay, they included a few goodies PLUS two bearings FOC that I tried to add online but failed.

So I will start on this this afternoon and post pics as its being out together.

Did you get some shims to set the pinion?

Matt Baxter said:

Did you get some shims to set the pinion?

Click to expand...

No I didn't, I can always grab some shim steel if I need it but as I haven't a dial gauge.....................

TIME TO REBUILD THE FRONT DIFF

So now that the bearings have arrived I went into the garage to replace the bearings. The first problem I have is that I have no vice and no real tools other than the normal stuff you would have. So holding the bloody thing whilst undoing the pinion castle nut was interesting and called for some ingenuity.

Firstly here's all my bearings I purchased from British Parts. Enough for both diffs, the front plus a spare and the odds and sods for the wheel bearings and transfer box.



Here is the pinion housing ready for stripping the diff out



Firstly I had to undo the pinion shaft castle nut. No vice so I clamped a piece of steel box section to the flange and sat it on the garage floor. It worked!!socket is 26mm



Then before removing the nut I removed the diff from the carrier housing. Firstly mark each side of the diff carrier bearing caps and then remove the split pin on their top. I kept them half way in so I didn't loose them






Then take out the locking tab and undo the bearing cap bolts. Don't loosen them right off. You have to count how many revolutions the bearing preload screw turns before coming out. This is the castellated item at the top of the above picture.

Once these screws are removed I took off the bearing caps and removed the diff, placing it somewhere safe





Then I removed the pinion shaft and here you can see the bearing races.whilst they are not damaged or overly worn, there was a lot of play in the inner bearing



Here's the pinion shaft with the inner bearing still attached.



Here it is just before I removed it



Here is the pinion shaft arrangement. Oil seal, spacer (which is only on the front diff apparently but my rear has one too???) outer pinion bearing, shims, more shims to the inner bearing outer race, shaft and then the inner bearing inner race.



Unfortunately at this point my phone ran out of battery so no more photos but to build it back together is the reverse.

However........
When building the pinion shaft back into the carrier the new bearing preload is only 3nm which is just more than finger tight. Seems strange but it does feel right when turning it.

In rebuilding the unit, the preload screw on one side stripped its threads so I have had to use another and set the backlash by feel as I have no dials etc. the backlash between the crown wheel and the pinion should be 0.10mm to 0.17mm which is very little. I have done this by feel and see how we go. It's not rocket science is it?

Again I used the old outer races to drift in the new bearings. Now I have a small selection of these which are coming in really handy as time goes by.

S with the unit rebuilt, I just need to put it back into the Disco and then put the hubs back together and see how she is. Should be done tomorrow...

Well I spent a couple of hours, well three actually putting the diff back in. It was simple enough to do, but the rain and snow made it very depressing.

Well test drive over and I can report that the drone in fourth and fifth has disappeared completely leaving a silent cabin, (yeah), but the steering is still stiff so guess the steering box is next on my list of jobs to do.

if your still looking at beadlocks WestMids4x4

Well hello guys,

Yes it's been while but I have had the old girl parked up for summer and I have had my hands full with the Lotus 7 rep, which I'm glad to report is terrorising the locals around the nearby lanes and roundabouts!!!!!

Not sure what to do next to the disco but I have a few little bits to fettle so will be back posting pics and descriptions if you're interested.

Definitely interested. Should be starting my own project & thread soon. Been inspired by yours, Mr Noisy's and Drizz to name a few. Keep the updates and pics coming.

GreenHornet said:

Well hello guys,

Yes it's been while but I have had the old girl parked up for summer and I have had my hands full with the Lotus 7 rep, which I'm glad to report is terrorising the locals around the nearby lanes and roundabouts!!!!!

Not sure what to do next to the disco but I have a few little bits to fettle so will be back posting pics and descriptions if you're interested.

Click to expand...

any pics of your Lotus as an update!!

Hey Ian, good to hear an update, just dragged mine out today too

godzilla84 said:

Definitely interested. Should be starting my own project & thread soon. Been inspired by yours, Mr Noisy's and Drizz to name a few. Keep the updates and pics coming.

Click to expand...

............but not mine.

:mooning::mooning::mooning:

auf_wiedersehen_pet said:

............but not mine.

:mooning::mooning::mooning:

Click to expand...

Maybe it's a mud deficiency issue??

auf_wiedersehen_pet said:

............but not mine.

:mooning::mooning::mooning:

Click to expand...

Yes, yours as well, i did say "to name a few"

Mr Noisy said:

Maybe it's a mud deficiency issue??

Click to expand...

:screaming_bug_eye_f:screaming_bug_eye_f

Mr Noisy said:

mate, dont worry about it, yours isnt looking that bad.

ok so its a fair amount of work but:

its a huge relief when its all done

yours doesnt need that much work

its so much easier when the car is fully stripped.

and luckily it doesnt look anything like this:

as you can see there is a general lack of crossmember, various deficiencies in wheel arch and a serious case of repeat boot floor AIDS.

BUT it wasnt long before this

then a test fit like this

then some panels like this

then some paint like this

a new floor like this

and a very happy moment like this

go forth and weld!

Click to expand...

What colour is that? Nato green?

drab olive I think