Sierra Hub - wheel bearing play

[Peterx]

I have replaced the bearings in my front hubs which are from a 1992 Sierra Sapphire donor.
I used a good quality aftermarket supplier and the new bearings seemed to be identical to the ones I removed.(diameter and depth of bearing shells)
I have tightened the hub nuts to the specified torque but I still have noticeable play in the bearings. (Each hub has a pair of tapered roller bearings)
When rocking the wheel, I'm getting about 2-3mm play at the edge of the tyre.

What have I done wrong or is this normal on the Ford Sierra hubs?? The bearings were changed on the bench and everything was meticulously cleaned.

thanks for any ideas or suggestions.... (at the price of new bearings I don't really want to try fitting another set without understanding the root cause)

Has anyone else experienced the same type of issue?


...peter

[Robert in Cumbria]

Re: Sierra Hub - wheel bearing play

Not familiar with the Sierra hubs but how tight a fit were the bearings on the hub shaft? I had the same issue with my roadster on Triumph hubs, adjusted the bearings up perfectly and a load of slack at the rim. My bearing inner tracks were a slack fit on the axle shaft. My answer was to apply a little Locktight 'Bearing fit' on the inner of the bearing and the shaft before I finally assembled them, then adjust the bearings and leave overnight. Next day all was perfect.

Bearing fit doesn't set rock hard so it will all come apart when it has to.

[Peterx]

Re: Sierra Hub - wheel bearing play

Not familiar with the Sierra hubs but how tight a fit were the bearings on the hub shaft? I had the same issue with my roadster on Triumph hubs, adjusted the bearings up perfectly and a load of slack at the rim. My bearing inner tracks were a slack fit on the axle shaft. My answer was to apply a little Locktight 'Bearing fit' on the inner of the bearing and the shaft before I finally assembled them, then adjust the bearings and leave overnight. Next day all was perfect.

Bearing fit doesn't set rock hard so it will all come apart when it has to.

Thanks for the suggestion, Robert, but the bearings were a snug fit on the hub shaft.
It's as if the out bearing shells are not being drawn together enough? There was evidence that the bearings have been changed by a previous owner/builder so it's possible that I have a washer missing.
Does anyone know if there should be a 'splined washer' between the ABS toothed ring and the hub nut?

The Haynes manual shows a 'splined washer' but doesn't show the ABS ring?

[CABRIOBOB]

Re: Sierra Hub - wheel bearing play

Peterx

Was there a problem with the old bearings before you changed them ? as I have seen a similar problem before and it was not the bearings, but was the top suspension arm bush to the chassis bolt loose. If you are sure the new bearings are ok and the washer behind the nut is ok then tighten the nut up untill no side to side movment them back off slightly ensuring the wheel hub rotates freely.

[Peterx]

Re: Sierra Hub - wheel bearing play

Peterx

Was there a problem with the old bearings before you changed them ? as I have seen a similar problem before and it was not the bearings, but was the top suspension arm bush to the chassis bolt loose. If you are sure the new bearings are ok and the washer behind the nut is ok then tighten the nut up untill no side to side movment them back off slightly ensuring the wheel hub rotates freely.

Hi Bob,
It is definitely the bearings, since I can see the hub nut move when I wiggle the wheel. According to the Haynes manual, these are 'self setting on assembly' and you are supposed to just tighten the hub nut to 310-350Nm and not back them off.
Except in my case they have not 'self-set' !
.....peter

[cameronfurnival]

Re: Sierra Hub - wheel bearing play

That sounds bizarre Peter...I dug out a pic of the hub assembly for a cossie and will try to scan in the sapphire when I get home if its any different.
Capture.JPG

[Peterx]

Re: Sierra Hub - wheel bearing play

That sounds bizarre Peter...I dug out a pic of the hub assembly for a cossie and will try to scan in the sapphire when I get home if its any different.
[ATTACH]3038[/ATTACH]

Thanks, Cameron.

That is exactly what I've got and is the same diagram in the Haynes manual.
I have the splined washer (C) which on mine is an ABS toothed wheel. But I didn't inspect it closely to see if it makes any difference which way round to put it on the shaft.

I think I will have dismantle one of the hubs and inspect it closely which probably means another new oil seal

...peter

[cameronfurnival]

Re: Sierra Hub - wheel bearing play

the only thing I can think Peter is maybe one of the bearing cups didnt seat properly?

[Robert in Cumbria]

Re: Sierra Hub - wheel bearing play

the only thing I can think Peter is maybe one of the bearing cups didnt seat properly?

But wouldn't that make the bearing tight?

What about the spline washer hasn't seated properly? Or the torque wrench is telling lies? What's 350Nm in English... According to my calculator, 258Ft Lbs, in Anglo Saxon, bloody tight. Needs a heavy bolted down vice and a very strong wrench to go that tight. In fact It's just beyond the range a normal 1/2" torque wrench will click off at, should be a 3/4" drive really.

[Peterx]

Re: Sierra Hub - wheel bearing play

But wouldn't that make the bearing tight?

What about the spline washer hasn't seated properly? Or the torque wrench is telling lies? What's 350Nm in English... According to my calculator, 258Ft Lbs, in Anglo Saxon, bloody tight. Needs a heavy bolted down vice and a very strong wrench to go that tight. In fact It's just beyond the range a normal 1/2" torque wrench will click off at, should be a 3/4" drive really.

I'm with you Robert, if the bearing shells were not seated fully, I think the bearings would be tight.

Your also right that 350Nm is bloody tight. I mounted the hubs back on the car, replaced the wheels, lowered the car to the ground and then stood with both feet on the end of my 2ft long breaker bar. I'm about 150lbs, so I reckon that should give me about 300lb/ft. It was at the limit of my 1/2" breaker bar so maybe I need get a 3/4" bar and a length of scaffold pole. But I also think the tightness is to stop the hub nuts coming undone rather than squashing the bearings into submission

I think I'll have to take one apart and take some measurements to understand what is going on and take another look at the splined washer to see if it is free to move.
One theory in my head, ......could the grease create a kind of 'hydraulic lock'. There would have been grease between the two inner bearing cases which would have to be squeezed out and it is pretty cold in my unheated lock up garage? Maybe I should 'warm up' the hub shaft and try tightening again?

But that will have to be another day as there is a few inches of snow outside today.

[b_caswell]

Re: Sierra Hub - wheel bearing play

It would seem the nut is bottoming out before its taking up the play in the taper bearing but normally that would then require a split pin or locking tab on the nut ?? just thinking out loud

[Robert in Cumbria]

Re: Sierra Hub - wheel bearing play

I remember back in my Mini days there were two tight bolts, the flywheel and the gearbox mainshaft nut, they were both 1 1/2" I had a SnapOn 3/4" drive single hex deep socket specially for that job. I found that although a 1/2" drive should do the job, the greater rigidity of the 3/4" drive gave much better results, I could struggle with 1/2" drive and then try the 3/4" and it would come undone with apparently little effort.

However I think there must be more to this than JUST tightness. Either the bearings are wrong or that splined washer was displaced when you assembled it. On the face of it you need a shim behind one of the fixed cones or the assembly isn't being pulled together properly.

[cameronfurnival]

Re: Sierra Hub - wheel bearing play

yep that makes sense - if the cups aren't in far enough it will be over tight. Peter, you measured the bearings for width of both housing and shaft - what about height? I agree with the torque - its about locking it up tight -there isn't any compression in these like in more ordinary bearings (you know nip up and back off a bit) - that doesn't apply. Let us know what you find when its back on the bench??

[dogoncrazy]

Re: Sierra Hub - wheel bearing play

If the securing nut is bottoming out on the thread before all play is taken up then you'll be able to get a feeler gauge between the nut and serrated washer which must mean that the bearings/cups are not of the required dimensions. Are the cups/bearings in the right way round, though I doubt you'd be able to assemble the unit at all.

[cabrioman]

Re: Sierra Hub - wheel bearing play

Peter

The sierra brg race and brg outer cup are supplied as a machined matched pair, are you sure the brgs didn't get mixed side to side and end up as unmatched?

John