27 replies to this topic

[minivanman8]

Just replaced circlips in my diff output shafts before dropping he engine back in.

Only problem is the r/h output shaft has quite a bit of wobble.

Should I be concerned?

I assume it's these at fault?

http://www.minispare...ck to catalogue

[ACDodd]

Nope the ball bearing has nothing to do with it. Its the diff cage/crown wheel bronze bush. Its a machine shop activity to replace them. As a result they are not usually replaced when gearboxes are rebuilt as this add a chunk of Chang to the cost.

Ac

[minivanman8]

Hi AC,
Doesn't the bronze bush stop the pot joint from wobbling? Pot joints are still on the driveshafts (still in the car) rather than diff output shafts at the minute.

[minivanman8]

See video

[minivanman8]

[cian]

Way to much wobble

[minivanman8]

That's what I was thinking, just not sure what to replace to rectify...

[Ethel]

I wouldn't say so, that's what the bushes in the covers are for. You're quite a way from the bearing there, which exaggerates the play in the bearing. The bearings are really working as a pair to support the diff, the planet gears  balance the torque on either side of the output shaft so it can't create the side loads you are in the vid.

[minivanman8]

But it appears as though the bronze bush exclusively supports the pot joint:

Attached Files

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[Ethel]

It does, again there isn't much for it do because the pot joint and driveshaft is pretty well centred. Bushes are stronger than bearings because they have more contact area, a bearing would need more running clearance (as you've discovered) to wouldn't centre as well - not good for the oil seals.

 

The diff bushes are similar to the crank mains bearings in how they work.

[minivanman8]

Ok, so it's the bronze bushes that need replacing. If I'm not mistaken, they're part of the diff side case, so I could rob one off one of the spare boxes I have laying about right?

[minivanman8]

Just compared with my spare box with no pot joints installed.....it's the same, and upon removal of the side cover, it's clear the bush won't engage with the output shaft without the pot joint being installed, by which time it's the pot joint exclusively in contact with the bush.

Is that amount of movement to be of concern if it's only a product of the bearing itself?

[ACDodd]

Ok the shaft waggle is the cage bush as I mentioned earlier. The larger side plate bush supports the pot joint. Both need replacing to eliminate play. Both require machining operations to ensure concentricity and a precise fit.

Ac

[minivanman8]

Ok, so just to be clear, that's item 2 in this:

http://www.minispare...l.aspx?2~14~127

And the large bearing as per my original post is ok?

[Spider]

As well as the bushes, it'll also be the thrusts in the diff itself. They are fibre material these days, but many moons ago were bronze.

 

Until I started using Quaifes, I would either find an old Bronze set or cut new ones from a sheet.

 

This is the current thrust here

 

http://www.minispare...ck to catalogue