I just ned a wuick procedure about locking the nut of the front whel bearing.. one guy tells me to tighten it hardly like tightening a wheel nut.. buy my uncle told me that the beaing should be loosen with half a turn of more I'm

not sure to allow the bearing to expand under the effect of temperature..

does anybody know anything about it?? I dont want to destroy my whel thrust bearing by over tightening!

Mohamed.

Hi Mohamed

Looks like your Dad was right. The front hub nut needs only to be tightened slightly in comparison to a wheel nut.

From Haynes Automotive Repair Manual 206

Adjustment Of Front Hub Bearings

1. Adjustment of front hub bearings must be carried out if they develop excessive "play", whenever the hubs have been dismantled and reassembled or the bearings repacked with grease.....

2. Remove The road wheel and withdraw the disc pads.

3. Remove the dust cap from the end of the hub, using two srewdrivers as levers or or tapping it off with a small cold chisel and hammer.

4. Remove the split pin from the castellated nut.

5. Using a torque wrench, tighten the hub nut to 22lb/ft (3.0 kg/m) at the same time rotating the hub in its forward direction.

6. Unscrew the hub nut 60 degrees and then fit a new split pin and bend over the ends. If the split pin hole in the stub axle does not correspond with the hole in the castellated nut, move the nut in the loosening (anticlockwise direction).

By comparison to the Haynes notes the FSM Datsun 260Z also advises or differs by saying :

1. Jack up the car first and place on jack stands

2. That the nut should be tightened to between 2.5 and 3.0 kg/m (18-22 ft/lb) torque.

3. Advises rotating the wheel hub a few turns in both directions to seat the wheel bearing correctly before retightening the spindle nut.

4. The hole and nut may be loosened out from 60 to as much as 75 degrees total to allow alignment.

5. It then recommends again spinning the bub in both directions to see if it rotates freely before measuring bearing preload using a spring balance.... procedure described

More notes follow in both references but I think this sorts your immediate problem. The Factory Service Manual or the Hatnes manuals are among a number of good references to have on hand for moments such as this.

Here's a scan of the page from the FSM:

Tighten the nut up until it's touching the assembly, then back it off a very little bit (like 1/4 of a turn) until the rotor spins freely, but does not wobble if you pull on it.

The FSM and How to Rebuild Your Datsun book also indicates that there should only be approximately 1 lb of force required to turn the hub. You can measure this by attaching a spring scale (like a fish scale) to one of the studs and pulling on it until the rotor spins. The force required to spin the rotor should be approximately 1 lb.

I just ned a wuick procedure about locking the nut of the front whel bearing.. one guy tells me to tighten it hardly like tightening a wheel nut.. buy my uncle told me that the beaing should be loosen with half a turn of more I'm

not sure to allow the bearing to expand under the effect of temperature..

does anybody know anything about it?? I dont want to destroy my whel thrust bearing by over tightening!

Mohamed.

You can make this a complicated endeavor if you wish , but your uncle is correct. Tighten the axle nut down firmly , about a turn or so past finger tight. spin the wheel a few revolutions each directions. Back off the Axel nut until loose , do not turn the wheel when doing this part. Then tighten the nut finger tight plus 1/4 turn . spin the wheel . now grasp the tire , from the front and back and see if you can feel any play or looseness. If ANY is felt tighten the nut slightly until none is felt and the tire turns freely. You want the bearing to be only slightly under tension or load ,but not loose . If too tight the bearing will fail from too much friction. If too loose it will also fail because of miss alignment to its race in the hub . If you have just replaced the bearings or cleaned the old ones , be sure to use grease for a wheel with disk brakes and also be sure that the grease is pushed into and through the bearing holders so all the voids are full . All the best . Gary USE A NEW COTTER PIN , YOU DONOT WANT THE AXEL NUT COMMING OFF !

first of all, thanks to all of you for the rich information with documentation attachments (as usual by Stephen)

and sorry for not following up this post, I was in bed for few days due to sudden illness which I guess my Zed was involved in it since I was cleaning, painting and replacing shocks and springs right after my night shift:stupid:

I really love this forum, I don't to be an auto mechanic to fix my car and I don't even need one since I joined this forum..

thank you guys..

wish you all the best..