<VV> Loose axle

[William Hubbell]

Hugo,

Think about it - the weight of the car is resting on the tires, which are lateral to (outboard) the wheel bearing.  The wheel bearing is acting as the fulcrum of a lever, with the wheel and tire at one end and the u-joint yoke at the other end.  Because the bearing allows angular movement, when the weight of the car is on the tires, that end of the lever is forced upwards, when in turn will force the yoke end downwards.

This is easily demonstrated by noticing the change in camber of the wheel from when it is raised off the ground to when the weight of the car is resting on it. 

Bill

> On Mar 5, 2020, at 10:54 AM, Hugo Miller via VirtualVairs <virtualvairs at corvair.org> wrote:
> 

Yes indeed - I'm with you. As soon as I gave this some serious thought, I realised this set-up would only work with a self-aligning bearing. BUT ... if - IF - the weight of the car sits directly over the bearing (as it should, pretty much) there won't be any force acting on the shaft. I guess it is probably off by a bit, but I still don't reckon it should be by much. What I'm going to do is stick a big lever in there & see if I can get any movement at the inboard end of the shaft.
Having said all that, however, my initial reason for checking the shafts was to see if they might be the cause of, or contributing to, my wheel wobble that goes in & out of phase. If indeed there IS a load on the axle shaft coming from the weight of the car, then it isn't going to wobble anyway! It may run slightly out of line, but it will at least run true.

> On 2020-03-05 09:53, Doug Mackintosh wrote:
> Hugo, the wheel bearing allows angular movement since the suspension
> arm/bearing mount does not stay in alignment with the axle shaft as
> the suspension arm moves. As a result, when the tire is pushed upward
> (e.g. when the car is resting on the tires) the axle assembly can
> rotate about the wheel bearing which will push down the differential
> end of the axle. So I think when you rest the car on the ground it may
> push down at the differential end and make the slop disappear. Not
> sure how much force there would be at the differential end, but likely
> enough that you would not be able to push it with your hand.
> 
> <<Date: Thu, 05 Mar 2020 00:51:04 -0500
> 
> From: Hugo Miller <hugo at aruncoaches.co.uk [1]>
> 
> To: Jim Becker <mr.jebecker at gmail.com [2]>
> 
> Cc: <virtualvairs at corvair.org [3]>
> 
> Subject: Re: <VV> Loose axle
> 
> Message-ID: <9999202a7456d0bb32d4528e718c4e5e at aruncoaches.co.uk [4]>
> 
> Content-Type: text/plain; charset=UTF-8; format=flowed
> 
> Alignment? What alignment? Are you saying thew rear wheel alignment
> 
> will change if there is no engine or drivetrain in the car? Because
> the
> 
> weight of the car will push upwards on the outer end of the axle
> shaft
> 
> and downwards on the inboard end? Is that your point? I see what you
> 
> mean, but there's a double taper roller bearing at the outer end,
> isn't
> 
> there, that I would have expected to hold the whole lot in alignment.
> 
> Why doesn't it? Or is it a self-aligning bearing? That might explain
> why
> 
> the tapers look the wrong way round? But then again, if it's
> 
> self-aligning, it shouldn't be exerting any force in ANY direction.
> This
> 
> all seemed so simple till I started thinking about it!
> 
> But when I grabbed it earlier, I was pushing more forwards and
> 
> backwards rather than up & down, as I was reaching under the car to
> do
> 
> it. I'll try it again tomorrow with more force & see if I can get
> 
> anything to move.>>
> 
> -- Doug Mackintosh Corsa member since 1996 Corsa/NC member since
> 1996, Virtual Vairs member Corvair owner 1969-1971 and 1996-on
> 
> Links:
> ------
> [1] mailto:hugo at aruncoaches.co.uk
> [2] mailto:mr.jebecker at gmail.com
> [3] mailto:virtualvairs at corvair.org
> [4] mailto:9999202a7456d0bb32d4528e718c4e5e at aruncoaches.co.uk

_______________________________________________
This message was sent by the VirtualVairs mailing list, all copyrights are the property
of the writer, please attribute properly. For help, mailto:vv-help at corvair.org
This list sponsored by the Corvair Society of America, http://www.corvair.org/
Post messages to: VirtualVairs at corvair.org
Change your options: http://www.vv.corvair.org/mailman/options/virtualvairs
Archives: http://www.vv.corvair.org/archive.htm
_______________________________________________