Rear Hub movement.

[rob needs]

I've had the rear hub off and cleaned it all up and tightened it up good.Still the same amount of movement.The end of the shaft doesn't look that good.

I have another axle which looks like its never been used!It had black tape around the ends of the half shafts ,and the drain plugs look as though they haven't been out.The oil in the diff (whats left) has gone muddy but it feels smooth when turned.

I'm thinking of maybe putting the whole thing in,or whats needed to get rid of this movement, a new half shaft,a new brake drum.Its movement when holding the wheel top and bottom and each side.

Another thing,the bush at the top of the axle bracket needs to come out.The middle part is off centre,any tips on how to remove these?

[David Morris]

Hi Rob,

Oh dear! I've had this problem before, but on a hydro-mechanical rear axle. These are considerably weaker and smaller at the tapers than the full hydraulic axles. Which sort do you have? The full hydraulic axles are tough old birds and almost bomb proof.

Unfortunately, wear on the tapers seems to stem from the axle nuts not being fully tightened in the past and that wears the tapers, the keys and the slots. It should all look nice and sharp, but you do mention that it does look a bit dodgy.

However, are you sure it isn't wear in the outer bearings? Wear here can feel exactly the same as the movement that you mention. I suggest that you lock-up the brakes hard temporarily with the adjusters and then try again. If the movement is still there, it might be the bearings. There should be 0.006" to 0.008" end float in the bearings anyway, which are taper bearings and can be adjusted with shims.

So, it might not be as bad as you think!

If it proves to be the tapers and you have the same type of axle and it is as good as you say, then changing the half shafts will remove some of the wear. Is the 'new' axle complete with brake drums, as these will probably need to be changed as well?

I haven't had to change the bush you mention but on similar bushes, I have removed the pin and carefully sawn with a hacksaw down through the metal centre, through the rubber and then the outer shell of the bush, but carefully stopping when through the metal shell and before you meet the axle bracket itself. This usually allows some penetrating oil into the outer bush area and then it's out with the hammer and punch!

Hope this is useful.

All the best,

David

[rob needs]

Hi David, i have the full hydraulic brakes,i'll give the locking of the wheel trick a go.When you say outer bearing i take it you mean axle shaft bearing?Whats the form changing this one,would i need a puller.

I didn't really want to start striping bits off the other axle,thats why i was thinking of putting the whole thing in.Mind you i'd rather not,this one has no drums on it.



rob.

[Mike Allfrey]

Dear Rob,

With respect to the taper fit at the brake drum. All surface area of taper, drum and half shaft, must be spotlessly clean, no oil or grease, and of good fit. the axle nut should be tightened dead tight, the plain washer given a solid thump with a heavy hammer and hollow drift, and then the nut should be re-tightened until the split pin can be installed. DO NOT back off the nut to fit the split pin! This is basic trade knowledge.

Using this procedure, 200 hp can be transmitted via the taper match up without a key!

I would venture to guess that all Javelins and Jupiters have worn rear axle shaft bearings. The full hydraulic Salisbury axle uses a common Timken bearing. You will not need a puller, you will need a press! I have written up some technical notes on the rear axle shaft bearing adjustment procedure. Give me your E-mail address and I will send a copy.

Good luck,

Mike Allfrey.

[rob needs]

I removed the hub in question today and took away one thin shim.It was still loose when i put it back together,felt good at rocking the wheel at 1/4 to 3,but movement at the 6 0'clock position.I'm not talking massive movement,but movement all the same.

[rob needs]

I've put the thin shim back on and removed the thickest one,and this seems to have done the trick.Cant feel any end float,but i couldn't before i striped it down.

[Forumadmin]

Check the taper and see if it is shiny. If it is, then the hub has been moving on the taper. It is then likely that the fitting is worn. It may be possible to fix this with some 1 or 2 thou shim stock although there is a danger that this will cause some runout or misalignment. It may also be fixed by filing or grinding the shoulder on the shaft so that the hub goes further on the taper. Both of these are bodges and are no substitute for replacement or proper reconditioning.

[David Morris]

Hi Rob,

Glad that you have solved the hub movement problem. Good news!

I do have a few of these shims of different thicknesses, if you ever need them.

All the best,

David

[rob needs]

Thanks David,keep it in mind.
rob.