110 diff oil seal

[dodgy 110sw]

hi

I wonder if anyone can help me, i am trying to replace the oil seal on a 1990 110 station wagon and after looking at the dodgy workshop manual i downloaded it does not look the same on the vehicle,

i have taken the prop and flange off the back diff and the oil seal appears to be inside the diff cassing,

and the one in workshop manual is externally, so how easy is it to replace an internal seal.

If anyone can point me in the right direction it will be much appreciated.

[Diff]

hi

I wonder if anyone can help me, i am trying to replace the oil seal on a 1990 110 station wagon and after looking at the dodgy workshop manual i downloaded it does not look the same on the vehicle,

i have taken the prop and flange off the back diff and the oil seal appears to be inside the diff cassing,

and the one in workshop manual is externally, so how easy is it to replace an internal seal.

If anyone can point me in the right direction it will be much appreciated.

Hi Dodgy,

I suspect the confusion comes from the type of seal you are looking at. The oil seal commonly fitted to the Salisbury axle on the back of your 110 has a metal casing with a rubber centre. This means that the front face of the seal is metal and it may look to you as though it is part of the diff housing and that the rubber seal part is fitted from inside the diff housing. This isn't the case and the seal can be levered out in the normal way. The replacement seal you have might be the wrong one (possibly for a Rover type diff - like your front one), or it could be a different type but the same dimensions as the original.

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

[dodgy 110sw]

Cheer's diff will try that, just hope the weather gets a bit better, dont fancy crawling under in this weather.