diff stripping

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Big_M_
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Sat Oct 01, 2005 7:27 pm

lads,

i want to strip and re-build a diff on me e30 325i sport.
anyone have a good link or better still have experience of re-building one.
as there is not many people around my area who speicalise in this type of work.
and i don't want to give it to a chancer who will f**k it up you know.

it can't be that difficult can it???????????
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Brianmoooore
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Sat Oct 01, 2005 9:20 pm

The main problem is torqueing up the pinion flange nut correctly,as this crushes a deformable sleeve as its tightens qnd sets the clearance, I assume, between the crown wheel and the pinion.
Big_M_
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Sat Oct 01, 2005 9:34 pm

well thats more than i knew about it brian, any other idea's links with pictures or something would be great as i'm sure alot of zoners have come across this problem and if were able to repair their diffs it could save alot of pain from having to try and source a replacement. the clutch pack for the diffs are i think about 180euro's, that's what i've been told that only about 120 pounds and your diff ia A1 afterwards, hopefully!!!!!
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Brianmoooore
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Sat Oct 01, 2005 9:48 pm

If it's LSD's your rebuilding, then it might be possible (I'm only guessing) to remove the crown wheel/ diff without disturbing the pinion assembly.
No experience of LSDs, but I've read on here, that the clutch packs to use are those for, IIRC, a Ford Atlas unit.
You can either use just part of the replacement bits, or have your LSD housing machined to accept the other bits as well, and end up with an improved unit.
E30BeemerLad
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Sat Oct 01, 2005 9:51 pm

i think the problem with rebuilding a diff yourself, even if you know what you're doing is that half the time, the cost of the bearing kit and then the seal kit and any other bits n pieces equal the cost of sourcing a second hand unit, maybe's not quite the same figures for LSD boys, but for anyont with an open diff that is noisy, you are better off buying a quiet diff from a breaker.
Templ8e30
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Sat Oct 01, 2005 10:53 pm

It's an arse of a job best left to a pro.

For starters the inner pinion bearing must be warmed up and the pinion shaft frozen to get the bearing on, it's that tight a fit :?

Secondly it's very difficult to set-up the pinion/crownwheel backlash and mesh pattern without lots of shims and the right tools.

I tried and spent countless hours doing it, I wouldn't attempt it again.

Cheers,

Iain T
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Brianmoooore
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Sat Oct 01, 2005 10:56 pm

Templ8e30 wrote:It's an arse of a job best left to a pro.

For starters the inner pinion bearing must be warmed up and the pinion shaft frozen to get the bearing on, it's that tight a fit :?

Secondly it's very difficult to set-up the pinion/crownwheel backlash and mesh pattern without lots of shims and the right tools.

I tried and spent countless hours doing it, I wouldn't attempt it again.

Cheers,

Iain T
Is it possible to get the crown wheel and diff unit out and in without disturbing any of this though?
Demlotcrew
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Sat Oct 01, 2005 10:58 pm

^ yeah i think so!

Andrew
Templ8e30
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Sun Oct 02, 2005 8:59 am

It Is possible to remove the crown wheel out yes but the crownwheel/pinion are a matched pair and shouldn't be mixed with other crownwheel/pinions even of the same ratio.

If you were to swap the clutch unit for example, the bearings will need reshimming to ensure the correct load on the bearings and keep the mesh in spec.

It's a complex thing to set up :(

Cheers,

Iain T
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M3Compact
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Sun Oct 02, 2005 9:06 am

All the Crown wheel and LSD etc can be removed/reset, without disturbing the pinion.

Agreed, pinion bearing replacement can be a pita. :evil:
Big_M_
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Sun Oct 02, 2005 7:43 pm

but if you only remove the diff unit, and the pinion is not removed the no need to adjust the backlash as it is already set up from before. the part i would be worried about is going into the diff, there is not much info to be got on the web either. it can't be too difficult thought couple of gears, clutchs and some gear marking compound to see if your backlash is set correctly and gears are engaging enough. its only the clutch pack i want to replace as the there is no whining from the diff.
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Big_M_
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Mon Oct 03, 2005 12:18 pm

Brianmoooore wrote:.
No experience of LSDs, but I've read on here, that the clutch packs to use are those for, IIRC, a Ford Atlas unit.
You can either use just part of the replacement bits, or have your LSD housing machined to accept the other bits as well, and end up with an improved unit.
IIRC, would this be available form any ford dealer, any model ATLAS or specific model
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Brianmoooore
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Mon Oct 03, 2005 2:49 pm

Big_M_ wrote:
Brianmoooore wrote:.
No experience of LSDs, but I've read on here, that the clutch packs to use are those for, IIRC, a Ford Atlas unit.
You can either use just part of the replacement bits, or have your LSD housing machined to accept the other bits as well, and end up with an improved unit.
IIRC, would this be available form any ford dealer, any model ATLAS or specific model
Don't know. This is stuff I dimly(and probably incorrectly) remember from a previous thread on the forum.
slideways
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Mon Oct 03, 2005 6:53 pm

i've done this clutch replacement thingy and it handy enough if thats all ya have to do. no need to take down diff casing even.
just remove the mounting bolts from the back of the diff. disconnect the two drives. reomve the bolts from the plates that are around the drives and the back plate on the diff. with the crown wheel supportted wit a timber wedge work the two bearing supports out of either side of the casing. mark their positions first. once out the whole assy willl clear betwen the diff casing and wheel well. then into a vice undo the ring of allen blots, tappy tappy and out the whole assy will come.
i have a half set of clutches in sligo if you are local.
slideways
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Mon Oct 03, 2005 6:53 pm

sorry. told me post wasn't workin, some bug thingy and i kept tryin
Last edited by slideways on Mon Oct 03, 2005 6:57 pm, edited 1 time in total.
slideways
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Mon Oct 03, 2005 6:55 pm

:oops:
Last edited by slideways on Mon Oct 03, 2005 6:58 pm, edited 1 time in total.
Big_M_
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Mon Oct 03, 2005 6:57 pm

done some enquiring today and yas the atlas is a back axle used by ford on the mexico etc,etc. the clutch packs will do, i just have to strip the diff now measure the thickness of the of the floaters and i'll be able to get the required pack made up. diff here i come, but before i do i was advised to check for wear on the front and rear anti-roll bars and to check that the rear shock are adjusted to the same stiffness.

thanks for the help lads. :)
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