Cyclical binding sensation

[sparkywig]

Hello hive mind, me again.
I've just installed a new gearbox with short axle conversion and disc kit.
I'm now getting a cyclical binding feeling and periodic noise from the nearside rear hub. We've stripped, checked and re-assembled both hubs but the noise and sensation is still there.
When rotating the n/s rear wheel there is no bearing play until you get to a certain point, it then goes as you rotate the wheel further.
Is this the symptom of a bent axle shaft?
It's the only explanation I can think of.

[purplepeter]

Have a look at the alignment of Torsion Tube & drive shaft.. Are they absolutely parallel?/is the gearbox absolutely central?
There was a tool for doing that, with a U shaped bracket to go over the torsion tube & A L shaped one at t'other end with a turnbuckle in between, But a sash clamp works just as well
I know that doesn't entirely answer the binding, but it's a starting point
Beyond that, You've got the inner & outer bearings the right way around? & the Hubnut properly torqued?

[purplepeter]

Substitute Axle tube for driveshaft! I was thinking IRS!
Might also be worth pulling the brake pads out to eliminate brake binding from the equation

[sparkywig]

Done that Peter, tried it without pads. But then discovered the offside disc runs out as well. Eliminated this from the current problem, but next on the list.

Somebody else has suggested one of the fulcrum plates may have become dislodged in the diff.

[937carrera]

How old are the bearings ?

If roller bearings, is it possible that one of the rollers has developed a flat spot ?

Someone advised me recently that use of molybdenum disulphide grease can cause this (it's too slippery and the roller stays in one place wearing instead of rotating)

[sparkywig]

If it's the bearing, wouldn't there be play at all wheel positions rather than just the one place?
I would prefer it to be a bearing issue rather than have to drop the engine and 'box again.

[broady_6]

If its as david has suggested and just one roller has a flat then the issue would only appear at one point. Rather than a uniform failure all the way around the bearing

[937carrera]

If all the rollers are round then no play.

If one of the rollers has a flat then there will be play on that axis

That was the theory anyway, I'm not necessarily convinced, but better to mention it for you to consider, here's a link

https://www.machinerylubrication.com/Re ... ght-grease

[broady_6]

Would it be woth disconnecting the driveshaft at one end and then spinning the hub in isolation of the rest of the drive train?

[sparkywig]

It's swing axle Jim, the only way of isolating the drive shaft is to remove it from the diff.
I wish it were IRS, so much easier to work on.

[broady_6]

That'll learn me. I need to pay more attention!

[sparkywig]

I’m now wondering whether the runout on the offside disc is causing the binding effect, and it’s the n/s wheel bearing causing the noise.

[937carrera]

Put the car on axle stands at the rear, wheels off (just to reduce weight and rotating mass on the drooping wheel), pads in/out and see what you can hear when the wheels are being driven

2nd / 3rd on tickover should be plenty

[sparkywig]

Yes, going to use the 4 post wheel free ramp at Nick’s. But giving him a break from my vehicles for a few weeks.