Technical Front hub nut torque

[dirkdeman]

I've refurbished the front steering knuckles, wheel bearings and brakes. I've put the brake drum on the backing plate and fitted a new hub nut. The Haynes manual says to tighten it to 7Nm, or if you don't have a torque wrench with that setting (I don't, mine starts at 22Nm), hand tighten it and back it up 1/3 turn. Can anyone confirm this? Is it supposed to be that loose? I know that you 'secure' the nut when tapping the peen into the ridge, but it seems awfully loose for such a critical thing... especially when the rear hub nut is supposed to be tightened to a degree that I lift the car with the breaker bar sooner than the desired torque is being met...

(Edit: I have a 126 first series, which is the same as the 500R. As I understand for the earlier 500s different torque settings apply, but not THAT different)

 

[the hobbler]

I've refurbished the front steering knuckles, wheel bearings and brakes. I've put the brake drum on the backing plate and fitted a new hub nut. The Haynes manual says to tighten it to 7Nm, or if you don't have a torque wrench with that setting (I don't, mine starts at 22Nm), hand tighten it and back it up 1/3 turn. Can anyone confirm this? Is it supposed to be that loose? I know that you 'secure' the nut when tapping the peen into the ridge, but it seems awfully loose for such a critical thing... especially when the rear hub nut is supposed to be tightened to a degree that I lift the car with the breaker bar sooner than the desired torque is being met...

(Edit: I have a 126 first series, which is the same as the 500R. As I understand for the earlier 500s different torque settings apply, but not THAT different)

I always got taught that the correct adjustment for a "bearing adjustment nut" was to gently tighten the nut until you loose all play, and then just back it off a shade. At that point the wheel should turn freely, but with no discernible play. I always adjust the front hub with the wheel ON, so that you can check for play (or lack of it) as you tighten the nut. This procedure IS different from the rear hub-nut adjustment being that there is a collapsible spacer between the bearings in the rear hub.

 

[smart51]

It is tightened up by almost nothing and feels wrong. I checked mine a few times after short journeys because I couldn't quite believe it was right. So far, my front wheels haven't fallen off.

 

[bugsymike]

As advised above many older cars had a simple adjustable taper bearing set up on front hubs, if overtightened they will seize up so follow the advise from the other posters.
The main thing is once correctly adjusted then the securing method needs to be done correctly, if it is a peining into a slot with a blunt chisel sometimes it is best to use a new hub nut. I always preferred the Fords of that era as they only required a new split pin through a castlated nut.

 

[the hobbler]

As advised above many older cars had a simple adjustable taper bearing set up on front hubs, if overtightened they will seize up so follow the advise from the other posters.
The main thing is once correctly adjusted then the securing method needs to be done correctly, if it is a peining into a slot with a blunt chisel sometimes it is best to use a new hub nut. I always preferred the Fords of that era as they only required a new split pin through a castlated nut.

Hi Bugsy----the original system with the 500s front wheel-bearings WAS a castelated nut and split-pin---there are times when progress isn't always forward!

 

[bugsymike]

Hi Bugsy----the original system with the 500s front wheel-bearings WAS a castelated nut and split-pin---there are times when progress isn't always forward!

Shame, probably accountants saw a small profit increase.
I always have a box of split pins handy.