hi guys,

trying to work out the correct sequence to tighten the hub nut on my mk 1 vrs.

ive read a few variations - but this one comes up a few time -

Stage 1: 225NM or 166lbft

Stage 2: Turn wheel Hub at Least 90'

Stage 3: Apply a further 50NM or 37lbft

Stage 4: Angle tighten a further 60 degrees. (equivalant to 2 points on a 12-point nut)

but ive read some posts that say between stage 1 and 3 - you loosen the nut 1/2 a turn.

Now this all makes quite a difference, i tightened mine without backing it off half a turn and now about 100 miles later the bearing is gone...

can anyone confirm the correct way to do things

Taken from workshop manual - for info

If the wheel bearings are loaded through the vehicle's own weight, the wheel bearing will be initially damaged. This shortens the life of the wheel bearing.

– Depress brake pedal (assistance of second mechanic required).

– Tighten new twelve-point nut to 225 Nm and release by 1/2 a turn.

– Torque wheel hub a further min. 90°.

– Tighten twelve-point nut:

Tightening torque:

50 Nm + 60

Hi

 

Having read the reply I agree 100% as this is what my Haynes manual states

 

BTW does any one know the size of the hub nut please as i need to change cv joint but cant get past removing hub nut

I'm confused with Stage 3 from the Haynes manual:

 

-Rotate wheel hub through at least 90 degrees.

 

Obviously the car is on stands at this point. Does this mean just rotate the wheel round 90 degrees? What affect does this have?

I can't see how you can turn the wheel angle 90 degrees.  

 

Stage 5: angle tighten

This makes sense - tighten a further 60 degrees while wheel is turned in or our at an angle

Because when you tighten the bearing to 225nm initially you are pre loading the bearing, by rotating the wheel you are removing some of it because you have slacked the nut off 180 degrees. it then means you are just tightening the bearing from then on and not preloading if that make sense to you?. Please speak up if not, as I am not the best at explaining things sometimes

Mine has the simple hex nut 30mm. No 12 pointed stretch bolt or anything.

Read on one blog that its 200nm then 180 degrees more.

Or do i follow the same 5 stage procedure for the standard hex nut?

Thanks

Edited 18 August, 201510 yr by Brit24

Because when you tighten the bearing to 225nm initially you are pre loading the bearing, by rotating the wheel you are removing some of it because you have slacked the nut off 180 degrees. it then means you are just tightening the bearing from then on and not preloading if that make sense to you?. Please speak up if not, as I am not the best at explaining things sometimes

Reading again I've confused myself.

Stage 1, 2 and 3  are clear.

Torque to 225, slacken 180 degrees and rotate wheel at least 90 degrees.

 

So what do stages 4 and 5 mean? tighten to 50Nm?? Or does that mean tighten to 275Nm? (what is the torque going to be after slackening off 180 degrees?) Sorry for the daft question.

(working on engine heads, gaskets and bearings was so easy compared to this)

 

Or is the final torque (stage 4/5) 50Nm + 60 degree angle tighten?

Edited 18 August, 201510 yr by Brit24

Stage 1 225 nm preloads the bearing so everything is perfectly pulled to true and seated correctly.

 

Stage 2 slacken 180 degrees releases any load on the bearing again,

 

Stage 3 rotate the wheel at least 90 degrees ensures the wheel is free to rotate and moves the bearing internals to a new area of contact so accurate tightening and final bearing load can take place.

 

Stage 4 Tighten to 50 nm applies the bearing torque for normal load to remove free play.

 

Stage 5 Angle tighten a further 60 degrees applies the correct bearing preload allowing the wheel to rotate without overheating by using the nut thread pitch as the way to accurately calculate the final preload.

 

A complicated thing to get across really, but hopefully I made it across the gap

Stage 1 225 nm preloads the bearing so everything is perfectly pulled to true and seated correctly.

 

Stage 2 slacken 180 degrees releases any load on the bearing again,

 

Stage 3 rotate the wheel at least 90 degrees ensures the wheel is free to rotate and moves the bearing internals to a new area of contact so accurate tightening and final bearing load can take place.

 

Stage 4 Tighten to 50 nm applies the bearing torque for normal load to remove free play.

 

Stage 5 Angle tighten a further 60 degrees applies the correct bearing preload allowing the wheel to rotate without overheating by using the nut thread pitch as the way to accurately calculate the final preload.

 

A complicated thing to get across really, but hopefully I made it across the gap

Thanks matey. It's stuck in now I believe.

 

What confused me was the 50Nm. I imagined the torque would still be well over 50Nm after slackening 180 degrees from 225Nm.  I guess not.

 

Fingers crossed now I can get the 6 shaft bolts off (and access them! - automatic box) I can see myself having to rush to halfords to get a longer 1/2" extension. (Have a good 3.5 foot breaker bar)

 

Were only a few models released with the hex hub nut? I see references to the 12 point nut everywhere

Edited 18 August, 201510 yr by Brit24

Not sure on the nut thing, but your new shafts if you get them should come with a 12 pointer jobbie.

 

Just make sure the knuckle part of your breaker bar is up to the job, as I've seen people almost chin wings on tight bolts as the knuckle broke in two and they weren't expecting it.

 

Could be worth £500 on you've been framed to someone with a sick sense of humour.

Not sure on the nut thing, but your new shafts if you get them should come with a 12 pointer jobbie.

 

Just make sure the knuckle part of your breaker bar is up to the job, as I've seen people almost chin wings on tight bolts as the knuckle broke in two and they weren't expecting it.

 

Could be worth £500 on you've been framed to someone with a sick sense of humour.

My original nuts are hex. The new ones supplied on the shafts are also hex. Shouldn't be an issue should it?

 

I have just ordered another pair just in case.

 

Thanks I'll keep the knuckle in mind! Maybe I should have one spare just in case. Just done the nuts on another car and it breezed through them.

At the end of the day, a nut is a nut. so long as you torque it correctly and angle tighten it correctly you should be ok.

 

As to the knuckle bar, I have a snap on one that cost a kidney to buy that I almost never use, and a Halfords Professional one that I can say my son has worked to death and it still keeps on coming back for more. Very strong bit of kit.

Thats is a lot of hassle for that nut

53 minutes ago, Joe41 said:

Thats is a lot of hassle for that nut

 

It tightens the wheel bearing so it's to make sure that is correctly seated and loaded.

4 hours ago, Tech1e said:

 

It tightens the wheel bearing so it's to make sure that is correctly seated and loaded.

Thank god i read this because i thought you just tightened it up then torqued it up to the correct nm's with the weight of the engine with the wheel on the ground

Edited 20 June, 20197 yr by Joe41