steve200TDi

Torque setting for diff pinion nut

22 posts in this topic

Hi everyone,

I'm new on here and this is my first post.

I have a defender 90 200TDi

I need to change the diff pinion oil seal on my rear diff because it's leaking!, I've been reading the handy tech articles by Les Hanson which has helped.

What I want to know is the torque setting for the large nut (is it 30mm?) on the diff when you take the drive shaft off? I've heard that it's pretty tight!

And any advice or tips for changing the oil seal.

Thanks in advance

Steve

Share this post


Link to post
Share on other sites

If you assume that the nut is tight enough anyway, then make a mark on the nut and threaded bit it screws on and count how many turn to undo it. As long as you do the nut up until the marks are aligned - it'll be the same. Of course, some people just put a breaker bar on it and wind it on until the veins on their foreheads stick out!

Les. :)

Share this post


Link to post
Share on other sites

Steve,

The rover type diff has shims to set the the preload on the pinion bearings and a torque value for the pinion/flange nut of 130Nm which is 96lb/ft. That is the tightening torque, so to undo it will require a fair bit more.

Si,

110s with the Salisbury type rear axle, don't have a specific touque value for the nut. Here is part of an explanation on refitting the flange nut that I wrote for someone else which may help you:

Unfortunately there isn't a set torque figure for the flange nut. The idea is that the preload on the pinion bearings is set whilst the main part of the diff is removed from the axle casing.

When the axle is set up during initial building, the pinion/flange nut is tightened until the resistance required to turn the flange is 30 to 40 lbs inch without the crownwheel assembly fitted. This is NOT the torque setting for the nut.

Basically, when the nut is tightened it gradually crushes a special spacer between the bearings. A spring balance is attached to one of the propshaft bolt holes in the diff flange and the resistance to turning should be 30 to 40 lbs for new bearings, or 15 to 30 lbs for when reusing the existing bearings.

The actual torque wrench figure for the nut may vary from vehicle to vehicle to achieve the same preload on the bearings.

As you can appreciate, when changing the oil seal, it is a bit impractical to remove the whole crownwheel diff assembly from the back of the axle in order to check the bearing preload with a spring balance.

So, provided the axle is otherwise good and you can't detect any play within the pinion bearings before you undo the flange nut, you should do your best to ensure that the relationship between the nut and the shaft is exactly the same when you put it back together.

That is why you need to mark the nut and the end of the pinion shaft (as accurately as you can)before removing the nut and flange. When refitting the nut after changing the seal you should tighten the nut to the point where the marks are exactly the same. The flange should also be marked in relation to the pinion shaft too, just to eliminate any possible discrepancies which might occur if you refit it on a different spline.

Hope this helps,

Regards,

Diff

Share this post


Link to post
Share on other sites

Blimey!!

OK, will try to do that. Thanks!!

And there's me thinking Les's reply was taking the wee-wee.

Share this post


Link to post
Share on other sites
Blimey!!

OK, will try to do that. Thanks!!

And there's me thinking Les's reply was taking the wee-wee.

By the way, before you change the oil seal, make sure that the axle breather pipe, and its fitting on the axle case are completely clear of obstructions. The axle air expands as it heats up, particularly on a long run, and if the breather is blocked it can cause the pinion seal or one or both of the hub seals to leak. Sometimes if you clear a blocked breather, the pinion or hub seal stop leaking.

Regards,

Diff

Share this post


Link to post
Share on other sites

Thanks for the info Diff.

I think I have all the info and resources (spanners, sockets etc) now to complete the job.

All I need now is the oil seal and a nice dry weekend to complete the job!

Steve

Share this post


Link to post
Share on other sites

How do you check the breather pipe?

That ocurred to me too, but I don't know how to check it.

Sorry, Steve, for the mild hijack.

Share this post


Link to post
Share on other sites

That's alright!

What I did was take the breather pipe off by undoing the banjo connection. Then blow some air down it, using an air compressor or a tyre inflater. if you feel air coming out the other end, then your fine!

If not, I guess you could try flushing it out with water or poking some welding rod down the pipe.

These are a few ideas that I would use, but I haven't tried either of these as I have not had a blocked breather.... yet!

Steve

Share this post


Link to post
Share on other sites

Si you can't do the rear Salisbury diff pinion like an Rover diff.

Here's the diff post of mine with the Rover diff torque setting.

--------------------------------------------------------------------------------

If your diff pinion is leaking,before changing the seal check......

That the oil level is at the bottom of the level plug threads.

Remove the breather from the axle and check that the pipe is clear.

Either of those problems will push the oil out through the seal.

Only after you have checked these two things,wiped the diff nose clean and run the car for a good test and find the seal still leaking should you change the seal.

Now for the diff info....

--------------------------------------------------------------------------------

I'm only going to deal with the two most popular diffs here.

The Rover type.

The Salisbury found on the rear of the 110.

Removeing the prop.

Not an difficult job,just fiddly.You can use the special tool from Difflock or as I do some ordinary spanners.

The bolts SHOULD be fitted into the pinion from the back.Don't worry if they aren't.

Should you forget the bolts and you fit them from the propshaft PLEASE check that they clear the diff housing.

There's a reason fot this which dates back to the series one.In those days BSF bolts were used.On the back of the pionon flange was and still is a machined ring.That ring was to hold the bolt head in place while you undid the nut.Now that UNF bolts are used the head of the bolt no longer is held by that flange.

So.

Undo the nuts that you can get at with a long ring spanner.

Starting with the nut that the angle of the shaft allows you to get a spanner on.That nut is generally at the bottom of the prop at the diff end.I use two combination spanners.the open ended end to hold the bolt head and eithe the ring end or the open end as suits you.

When you have this nut off turn the prop so that another nut is easy to get at!!

Prop off

Rover diff.......

Undo the nut.

Remove the diff flange.

Remove the oil seal your favourite way.

Fit a new oil seal.

Check that the diff flange hasn't been damaged by any previously fitted oil seal,if damaged renew.

Run a smear of oil either onto the oil seal lip or on the diff flange where the oil seal fits.

Fit the diff flange.

Refit the nut and tighten to the correct torque as per the book.85lbf ft.

Salisbury Diff.

The Salisbury Diff has a measured spacer between the diff pinion bearings to achive the correct bearing pre-load.Any removal of the diff pinion nut upsets that pre-load.You are supposed to use a special collapsable spacer then measure that spacer every time you remove the pinion nut.

This way helps you to change the diff pinion seal without the resort to those special tools.

Remove the prop shaft.

Take either a center pop or a small drill and mark the pinion shaft near the outside of the shaft by the nut.Mark the nut so that BOTH the marks line up.

Remove the pinion nut,counting the turns as you do so.

Change the oil seal as the above information.

Refit the nut counting the number of turns until the two pop marks line up.

Refit everything.

Check the breather pipe tho see that it is clear.

Check the level of the diff oil.

The level should be JUST BELOW the threads of the level plug.

Get out bit.....

I've given yuo this information to help youto keep your pride and joy in good condition,to the beat of my ability.

It is you that are doing the job.DO IT RIGHT!!It's your fault if you ****** the job up........ Article Tools

Report Post

Show Printable Version

Email this Page

Subscribe to this Article

HTH

mike

Share this post


Link to post
Share on other sites
Thanks Mike!!

Print it off and keep. It's my work.

mike

ps

I could have made a lot of money changing seals where the breather was blocked.

Share this post


Link to post
Share on other sites

I'm still a bit concerned with changing it myself.

Has anyone had any problems torqueing it up to the said 130Nm, problems with it being too tight or too loose.

Does anyone know the part number for the pinion oil seal on 200TDi 1993 defender and any places locally (West Sussex) or websites (i.e. paddocks) to get the seals

Is this the correct one?

http://www.paddockspares.com/pp/DEFENDER/A...m_VA102733.html

Also is the torque setting the same for the pinion nut of the transfer box hand brake end?

Thanks for your help

Steve

Share this post


Link to post
Share on other sites

:angry:

Unfortunately, being unaware of the intricacies of the diff flange nut replacement I removed the nut when I was investigating the clunk in my transmission some time ago. It took me a lot of effort to remove it, so I tried to put a comparable effort when I was putting it back.

Now, is there any way to set the pinion bearings back to the correct preload? Provided I didn't overtighten the collapsible spacer, can't I just remove it and try to tighten it till the required resistance to rotation is achieved?

As I understand it, the spec applies to the bearings only; since I have a complete diff, can't I try to measure the resistance to rotation on the pinion free play?

Not sure if I'm making any sense here.

Jaroslav

Share this post


Link to post
Share on other sites

Yes I did the same. I changed the oil seal on my front diff (110). The flange was rattling around when I took off the prop shaft. I removed the castle nut, and flange, replaced oil seal then refitted flange and tightened nut up by hand til the flange felt light it wasn't loose.

Oil seal still leaks and breather pipe is clear. Me thinks I might need to tighten the castle nut up but not sure how tight to do it??

anyone know? I've read through the thread and it's looking like 130Nm but wanted to check.

Cheers

DAvid

Share this post


Link to post
Share on other sites

Hi David and Jaroslav,

From what you saying you both seem to have a 110 - am I right. If so then you probably have a sailsbury axle which has a crush tube. Tighten the flange back up on this axle is a lot more difficult that a 90 rear axle as it just has washer.

Hopefully someone will be along to explain more about completing the job on a 110.

Hope this helps

Steve

Edit: Sorry david just re-read, front diff!

Share this post


Link to post
Share on other sites

Hi Steve,

yeah it is the front diff. Do you know what the torque should be on the font diff castle nut?

cheers

david

Share this post


Link to post
Share on other sites

Hi David,

I changed my rear diff oil seal. What I did was to mark where the nut was and count the turns it took to take it off. Change the oil seal and then tighten it back up to the mark I made previously. Touch wood it hasn't leaked to this day. It only needs to be nipped up as it is on a spline and so it can't rotate.

I have found this torque value in the defender workshop manual, I think it describes it correctly

Differential drive flange to drive shaft ......................................................... 47Nm

Hope this helps.

Steve

Share this post


Link to post
Share on other sites

There is a lot of confusion going on here which has the potential to cause problems. It isn't helped by misleading descriptions in some manuals.

I suggest people re read my earlier post #4 near the top of this thread.

Some re capping: Standard Rover type diffs are fitted to the front AND rear axles of 90s, but ONLY to the FRONT axle of 110s.

The rear axle of a 110 (up until approx the middle of TD5 110 production, after which they changed to a Heavy Duty type Rover Diff) is a Salisbury Axle and is visually very different from the front axle.

A Rover type diff has the pinion bearings set up using shims and NO crushable spacer. So if you change the pinion oil seal you can re tighten the pinion nut to its Specified torque setting of 130 Nm or 95lbft.

A Salisbury Diff has the pinion bearings set up by a crushable spacer, so there is NO specified torque setting for the nut if you change the pinion oil seal. See my earlier post #4 for detail.

The nuts and bolts holding the propshafts to the pinion drive flanges have a torque setting of 47 Nm or 35 lb/ft.(in previous posts this has been confused with the pinion nut setting).

Hope this helps,

Regards,

Diff

Share this post


Link to post
Share on other sites

It does seem a little confusing especially with 110's.

It's strange, I thought Western posted up just before you about the torque setting?

Steve

Share this post


Link to post
Share on other sites
It does seem a little confusing especially with 110's.

It's strange, I thought Western posted up just before you about the torque setting?

Steve

I did but the info was wrong, so rather than have it cause confusion, I deleted it.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now