Wheel bearing adjustment - hole A or hole B?

[Mjit]

Hi,
Got a question on one or my personal deamons - front wheel bearing adjustment.

My d/s wheel's fine.  Rocking the wheel off the ground gives a little movement that you can hear/feel but not so much you can see it.

The p/s wheel on the other hand gives me a choice of no movement you can either hear or feel with the split pin through one hole or, if you back it off to the next possible hole/castellation pair so much movement you can not only hear and feel it you can clearly see it.

Should I go for the "my god that seems like a lot of movement" slot of the "according to the book this is too tight" one?

 

Having had a friendly MOT station 'just nip them up' as they were too lose to pass the test in the past, resulting in them being over-tightened, the outer bearing friction welding itself up/to the tip of the stub axle and fracturing the stub axle while on the motorway I'm a bit paranoid about the front bearings.  On the other hand I'm amazed by the strength of the disks/calipers, as they were all that kept the wheel on the car!

[Clive]

Just checking, but you do know there is more than one hole drilled through the stub axle? So rather than adjustments being 6, there are 12 positions. I don't like a lot of play, just enough I can feel it, no more. Modern bearings are just done up TIGHT and that causes the issues.

[Pete Lewis]

yes the basic spec is end float 0.002" to 0.008"  

at 0.008" it gives about 3/8" rock at the tyre /rim    ....we all take that as excessive and you get pad push back ...

one flat back from a hand light nip is generally about all you need ,  Clive's on the ball  have a clean and find the other hole 

you certainly dont want it pre loaded ....££££££s  will follow that idea 

if new felts have been fitted  recheck after a few miles.

dont pack the hub space with grease , this can cause over heating and wont lube anything , just wastes grease 

just deep grease the bearings 

 

Pete

[Mjit]

Yep, I know about the multiple holes through the nose of the stub axle.  This is the difference I'm getting between one hole/castellation and the next possible hole/castellation pair.  Maybe 10-15 degrees tighter.

How do you actually DO "hand light nip" tightness?  Is that just with fingers (very loose for me as the castellations tend to cut in to your fingers long before tightness) or is that with a socket on the nut, but only tightened with a hand around the socket (i.e. no wrench attached to the socket)?

 

Off to Le Mans in 2 weeks for the 24hrs so going through the usual per-trip worry phase

[Clive]

Know what you mean about sharp bits. I use a socket and bar, do up tight, then back off a tad. If I get significant movement I tighten up a bit. I am surprised the the combo of holes/slots doesn't give you what you want though. But I thick as long as the bearings are not done up hard and have even a tiny bit of movement you are OK. Works for me....

(And I know what you mean about CLM. Before than 2 weeks family holiday. And yesterday I had a few hiccups at an autosolo. Broke a bespoke brake cable, clutch cable sheared but fixed, and then had an off and think I have a bent lower wishbone. And I want to swap the diff too....)

[Nick Jones]

1 hour ago, Pete Lewis said:

 

dont pack the hub space with grease , this can cause over heating and wont lube anything , just wastes grease 

just deep grease the bearings 

Pete

Amen to that - just stripped the two front hubs from my project GT6, which had about half a tub each in them.  All blackened and nasty around the bearings but untouched everywhere else.  Plus, if you do use the car hard heat from the brakes will melt the grease until it runs out - and then no more brakes 

Nick

[Mad4classics]

7 minutes ago, clive said:

Know what you mean about sharp bits. I use a socket and bar, do up tight, then back off a tad. If I get significant movement I tighten up a bit. I am surprised the the combo of holes/slots doesn't give you what you want though. But I thick as long as the bearings are not done up hard and have even a tiny bit of movement you are OK. Works for me....

I always deliberate over this one too - loose is bad but too tight is worse.

I think the procedure for hand tight is for new bearing fitment and is with the bearings lightly oiled, caliper removed and rotating the hub by hand in the same direction as you tighten. Back to the next split pin hole, mark and then disasemble to pack bearings with grease.

For end float adjustment where the bearing is already packed with grease, my book says remove caliper and apply torque of not more than 5lb/ft while rotating in the same direction. Slacken to nearest split pin hole.

I think the nut is 1/2unf so should give approx 4thou difference per split pin / hole combination.

David

 

[daverclasper]

Just to add. My stub axle has worn a bit more at the bottom (though still very smooth), so gives a bit more play when rocking with hands at 12/6 o'clock. so if yours are like this, make sure there is still some play when rocking at 3/9 o'clock.

Dave