Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Roger on 26 March 2012, 14:00:44

Title: changed main diff seal
Post by: Roger on 26 March 2012, 14:00:44
Hi dont know what ive done wrong but after changing the prop diff seal and building it all back up took it for a run, gave off a cluncking sound from back end, put it back on ramps to look and now there's movement on the drive into the diff has something come loose inside and if so is the diff now buggered? :'(
Title: Re: changed main diff seal
Post by: Andy B on 26 March 2012, 14:11:17
Hi dont know what ive done wrong but after changing the prop diff seal and building it all back up took it for a run, gave off a cluncking sound from back end, put it back on ramps to look and now there's movement on the drive into the diff has something come loose inside and if so is the diff now buggered? :'(

Sounds like you've not tighened the nut up enough to give the correct 'pre-load' on the taper bearing on the input shaft to the diff. On the guide, Mark marks the nut relative to the casing so that you can tighten it up to something like it was before.
Mr Haynes gives a rolling torque figure, which is only quite low, but without a rolling torque meter all you can do is a best guess. Tighten the nut untill only just tight ie all the movement of the input shaft is gone & then back off very slightly. As said, all you can achieve is a best guess.
Title: Re: changed main diff seal
Post by: Kevin Wood on 26 March 2012, 14:55:14
How did you tighten the flange bolt?

There's a crush washer between the bearing races which allows setting of the bearing preload on initial assembly. The trick is to tighten the flange bolt to exactly the position it was previously in without leaving it loose or crushing the washer any further and messing up the bearing preload.

The chances are that one of two things has happened:

1) In returning it to the previous position, the bolt wasn't tight enough and it has loosened slightly. The play you now have is because the bearing has insufficient preload or the flange has come loose.

2) It was tightened a bit too much and the noise and play you now have are due to the bearing having disintegrated.

I think you are going to have to unbolt the propshaft again and check the flange bolt for tightness. Try to find your original marks and see if it has moved. If so, return it to the marked position and see if the play goes and the bearing rotates smoothly.