Output shaft bearings

I am fitting new output shafts bearing the manual specified a special tool to reload to 0.5nm however I have had no luck finding a suitable tool or adapter. I’ve found some online blogs where the advice is to tighten by feel until there is no free play. Obviously due to the crush washer there is no going back! I’ve done this but it was nowhere near as tight as others have suggested also the oil seal does not look very seated - picture below. Grateful for any advice.

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If a ‘crushable’ is used, James; there is no alternative but the preload. Which really is just a measure of the torque required to initially start the shaft turning. Which means incremental torquing followed by preload measuring - and the shaft must be reset back to allow the measuring of the preload rather than the force required to turn the shaft rather than the whole assembly…

A makeshift measuring assembly would be an arm with a suitable weight attached - computed to give the desired preload…?

That said; preload is usually associated with conic bearings…so…?

Frank
xj6 85 Sov Europe (UK/NZ)

I presume you have the version with tapered bearings.
Did you install a new crash sleeve and seal?
As Frank said, the preload is determined by the amount of torque needed to turn the shaft.

No it’s not, the seal should be flash with the housing.

Yes I fitted new crush washers so it should just be a case of tightening and using that gauge in your picture?

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Bear in mind when using ‘crushers’ (collapsible spacers), James; the nut torque reflects the force required to compress the spacer and that torque increases as the spacer compresses. It does not reflect the ‘preload’ required, which is a measure of the bearing play - which is correct when the collapsed spacer has the correct thickness.

In an ideal world; the torque required to collapse the spacer to the correct thickness would be the same in all situations - but, due to variables, it is not. Hence the procedure of torque, test preload - repeated until spec preload is reached…

As an aside; ‘collapsibles’ are used where using shims, repeated trial and error, requires inconvenient dismantling - and axial bearing play cannot be directly and accurately measured.

Frank
xj6 85 Sov Europe (UK/NZ)

Yes. It will take quite a lot of force to start the sleeve crushing, but then it’s a bit easier.
When it has just bit of play measure the force/torque required to turn the shaft, cause of the friction of the seal (what I called the Seal torque).
If you measure at the flange hole you will need about 5 lbs.in more.

I was gonna say, the way those crush sleeves are configured, I’d expect the torque required to begin crushing them to be considerably higher than the torque required to continue crushing them once they have begun to deform.

I have never liked those things. I can see how they’re just wonderful on a production line for putting something together once and being done with it, but I prefer a shim stack so I can torque the nut down snug without worrying about overcrushing.

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Whatever, Kirbert - the main point is that nut torque is not a measure of bearing play…:slight_smile:

I sure agree with you on crushable sleeves, but on the factory floor, torquing with preload reading is easier than repeated dismantling to get the right shim stack? And the same procedure if bearings are to be replaced - sleeve as a substitute for better quality control…? :slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)

Thanks for all the advice finally got some garage time this weekend and got them reassembled!