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[HerefordElite]

The best method I find (personaly) for splitting the ball joint is to:

1) Treat with a good penetrant (and WD40 is crap at this!)

2) Tap a small chisel into the hub pinch point to spread it slightly (dont go over the top!)

3) Apply a long lever to the base of the hub pinch point which levers against the end of the wishbone/ball joint assembly.

4) Strike the lever with a heavy hammer close to the ball joint to free the assembly.

5) Now use a long 1/2 inch extension (or other suitable drift) parralel to the strutt (feed it through the maze of pipes and wires so it touches the end of the wishbone/ball joint casting) to tap the ball joint the final 10-15mm out (it takes very little effort at this point, if its still tight repeat the lever trick)

I take it you do this after removing the pinch bolt :-/

Yep

Ta

Is it possible to remove the pinch bolt and wishbone without removing the caliper?

yes no probs

[markomega25]

[/quote]

Ta

Is it possible to remove the pinch bolt and wishbone without removing the caliper[/highlight

I guess so, but I could not get my 18mm socket on either the nut head or nut square. Even when I did after taking caliper holder off it still would not budge - I had to buy a Draper extending wrecking bar (400mm to 600mm) with 1/2 inch drive, and that got it off pretty smartish. Also useful to carry in the boot for the wheel nuts!!

One tip on replacing the wishbones, the front (horizontal) bearing needs to be torqued up with the car on the ground and bearing under load, virtually impossible to do unless you have a pit. What I did was note the angle the wishbones were at whilst car was on the road before even starting the job, I then positioned them to the same angle to tighten them up before re-engaging the ball joint. This method then requires a lot of down force on the wishbone to get the balljoint back into the hub. I found a 3 foot peice of 2x2 softwood wedged under the antiroll bar did the trick but a spare pair of hands is handy here.

[HerefordElite]

apparently the OOF recomended method (Mark?) is to tighten the front nuts as tight as possible with a normal wrench with the bones loaded i.e. car on the deck, then jack high and torque up  

[Marks DTM Calib]

Also correct.

I have never removed the caliper or anything, I just use the correct size socket (half inch), a short extension with bar and a ring spanner.

[markomega25]

Also correct.

I have never removed the caliper or anything, I just use the correct size socket (half inch), a short extension with bar and a ring spanner.

Maybe with my 1/2inch socket set (which is nearly 30 years old) the sockets were slightly too long or the socket shoulder was too thick, it def' fouled the caliper holder in some way. Anyhow it gave me the opportunity to check the calipers, pads and grease the caliper sliders.

apparently the OOF recomended method (Mark?) is to tighten the front nuts as tight as possible with a normal wrench with the bones loaded i.e. car on the deck, then jack high and torque up

That method sounds good to me, wish i had read that before doing the job. But even so space is severely limited on low profile tyres and i have a bad back!!

One other observation, I found that there was not enough clearance on the subframe indent to get a socket and vernier style torque wrench in (squarely) on the front wishbone bearing nut as the diameter of the ratchet head of the torque wrench was to wide.

Maybe again it is possible my sockets are longer, but soon got round that problem - used my spring beam torque wrench instead!!

PS: Heynes joke book says torque is 120nm plus angle tightening of 15 degrees plus another 30 degrees (ie. an extra eight of a turn) which is easily estimated if you don't have an angle gauge thingy guide.

[feeutfo]

Still dont understand the need for the angle tighten business. Why not just do it up to 130nm or what ever the equivalent is?

[Welung666]

Exactly Chris, why are we not still doing ft/lbs? Stoopid europe!  

[Entwood]

Still dont understand the need for the angle tighten business. Why not just do it up to 130nm or what ever the equivalent is?

Torque loadings are actually very variable ... the measure is the "stiction" usually between the bolt head and the mating surface, although in theory the thread also has "stiction" .. this is often screwed up by folks using oil, grease, spit etc etc that results in inaccurate torque values, especially at higher values.

The correct method of "tightening" is actually the "clamping" force .. the squeeze of the two materials (also called "preload").. this is what angle tightening tries to achieve . it takes the bolt into its "elastic" range, which is why it should ALLWAYS be done in two steps (those you think 15 + 30 = 45 in one go are doing it wrong !!). Angle tightened bolts should always be replaced.

If you want some in depth theory ...

http://www.hexagon.de/tasignat.htm

slightly more readable ..

http://www.boltscience.com/pages/tighten.htm

HTH

[feeutfo]

Still dont understand the need for the angle tighten business. Why not just do it up to 130nm or what ever the equivalent is?

Torque loadings are actually very variable ... the measure is the "stiction" usually between the bolt head and the mating surface, although in theory the thread also has "stiction" .. this is often screwed up by folks using oil, grease, spit etc etc that results in inaccurate torque values, especially at higher values.

The correct method of "tightening" is actually the "clamping" force .. the squeeze of the two materials (also called "preload").. this is what angle tightening tries to achieve . it takes the bolt into its "elastic" range, which is why it should ALLWAYS be done in two steps (those you think 15 + 30 = 45 in one go are doing it wrong !!). Angle tightened bolts should always be replaced.

If you want some in depth theory ...

http://www.hexagon.de/tasignat.htm

slightly more readable ..

http://www.boltscience.com/pages/tighten.htm

HTH

Hmm, i did a bolt up and it felt crap so i took the nut off and greased thread and mating surface, obviously it did up alot easier and 120nm was reached with less grunting, so with less friction you might argue that the clamping force would be greater.
 I sort of understand the description you kindly posted, but im having trouble getting my head round how turning a nut, which is all you can do with it, one way with a torque wrench is different to turning it to an angle afterwards.
So are we saying after a point(120nm in this case)that the stretching of or elasticity of the bolt is more important than the tightness of the mating surfaces? Or to put it another way, after 120 nm the bolt will be in the correct elastic zone when angle tightened by 30 plus 15, or whatever  the spec. is?

I now have a headache.

[Kevin Wood]

Tightening a bolt to a torque depends on the friction between the threads, as to how much clamping force you end up with.

Tightening to an angle (assuming the starting point is roughly the same, I.E. when the bolt has started to clamp) will stretch it by a pre-determined amount regardless of the torque required and will therefore give a more accurate clamping force.

Kevin

[Entwood]

As Kevin says ...  another example ...

On a dry nut/bolt you tighten to 80 Nm, then up to 120 Nm .. the bolt might only turn 1/8 of a turn due to the friction being high as the surfaces are dry

On a lubricated nut/bolt, the second tightening might take 1/2 a turn as the friction is far less.

The second bolt will have a higher clamping force as more of the bolt has passed through the nut.

To get the clamping force the same in both cases, tighten to 80 Nm then an additional 1/4 turn.

The use of the 80 Nm figure gives around the same starting point as friction values should not change too much with regard to lubrication at this level.

[feeutfo]

Still dont understand the need for the angle tighten business. Why not just do it up to 130nm or what ever the equivalent is?

Torque loadings are actually very variable ... the measure is the "stiction" usually between the bolt head and the mating surface, although in theory the thread also has "stiction" .. this is often screwed up by folks using oil, grease, spit etc etc that results in inaccurate torque values, especially at higher values.

The correct method of "tightening" is actually the "clamping" force .. the squeeze of the two materials (also called "preload").. this is what angle tightening tries to achieve . it takes the bolt into its "elastic" range, which is why it should ALLWAYS be done in two steps (those you think 15 + 30 = 45 in one go are doing it wrong !!). Angle tightened bolts should always be replaced.

If you want some in depth theory ...

http://www.hexagon.de/tasignat.htm

slightly more readable ..

http://www.boltscience.com/pages/tighten.htm

HTH

Hmm, i did a bolt up and it felt crap so i took the nut off and greased thread and mating surface, obviously it did up alot easier and 120nm was reached with less grunting, so with less friction you might argue that the clamping force would be greater.
 I sort of understand the description you kindly posted, but im having trouble getting my head round how turning a nut, which is all you can do with it, one way with a torque wrench is different to turning it to an angle afterwards.
So are we saying after a point(120nm in this case)that the stretching of or elasticity of the bolt is more important than the tightness of the mating surfaces? Or to put it another way, after 120 nm the bolt will be in the correct elastic zone when angle tightened by 30 plus 15, or whatever  the spec. is?



I now have a headache.

So... er... Yes?