[edward]

I have had a look on various web pages etc, but I am trying to find an accurate figure for the torque for the front main hub nut. Things seem to range anything from 200Nm to 470Nm. I had a look at one manual and it said 427- 472Nm - but that just seems MASSIVE!

There are a few low value recommendation and some high ones. I think there may have been a smaller hub nut on earlier cars or perhaps the lower 200Nm I read occasionally is for the rear.


Does anyone have a view? / definite knowledge?

Thanks, E.

 

[sprint_veloce]

Assuming you mean a 33 front hub nut (36mm) then I would aim to get as close to 400 Nm as you can. FT.

Another trick if you're reusing the nut and you're sure it was good before just get it back to the same place and reuse the staking.

 

[edward]

Yes. FT.

Not using the same nut unfortunately.

I had thought to wind it onto 200Nm then take it to a garage and let them do the rest. I really can't see why any nut realistically needs to be done to 450Nm. (unless it was holding the propellor on a submarine!)

 

[sprint_veloce]

I just checked my Haynes manual and for the early outboard brake driveshaft hub nut they list 23 - 28 kgf m which is around 230 - 280 Nm. If your car has the larger 1700 and 16V driveshafts there may be a different torque setting, though I think the nut is the same.

 

[BANANA S0UP]

I was told 100lb/ft

 

[BANANA S0UP]

sorry i was thinking wheel nut. Just googled hub nut. my bad

 

[edward]

Yes, the car has the larger 1700 and 16v drive shafts.

I do recall seeing that on early cars they were in the region of 230-280Nm as you say (Sprint Veloce). I struggle to see why there is such a signicant jump to 427 - 472Nm for a shaft that I can't imagine is that much bigger.

I have thought of a how to apply such a force when tightening up the nut on the driveway. It is something like this:

Take a middle point (of the required torque range) at 450Kn which equates to 45.89Kg. I have a sturdy bar which is 2m long. So, connect it all up and hang a weight of say 23Kg on the end (minus the self weight of the bar) and should be job done. It is going to be interesting - but it saves me all of the messing around driving the car to a garage and asking them to tighten hub nuts to a high torque.

Any thoughts.....?

 

[fly33boxer]

Yes unfortunately the nuts for the 16v CV's are to be to 472nm, yes it does eeem excessive but is required to keep the two bearing shells snug.
There is a fair amount of stress in this area and requires this to keep the CV from moving around.

 

[edward]

Are there 2 but very similar shaft / spline options. I have about 4 hubs and shafts to pick from amongst all my spares. One hub would not fit onto one of the shafts as the spline was slightly different / smaller / finer. Is it a reasonable guess that the chunkier thread is the series 3 and the slightly finer one would be for a series 2. I think that the hub nuts appeared to be the same, but again never properly checked this. It was getting dark and I just wanted to get things finished off. I had to change one of the drive shafts to suit the hub I had modified. I am wondering now if I have a series 2 hub on one side and a series 3 on the other. Is there an easy way to tell them apart, if that is indeed what I have done?

 

[sprint_veloce]

The splined shaft on the outer cv into the hub flange is bigger on 1700 carbed and 16V (not 1.7ie I don't think) driveshafts, and from memory the driveshaft itself is a bigger diameter too. Most likely the inner CV joint is different as well, but it's been a long time since I had 2 side by side.

 

[edward]

Intersting.... What I have just been reading on other forums, as well as this one, is that series 2 cars had 28 splines on their drive shafts, Series 3 cars had 25 splines. The reason being that Alfa changed, later on, to a bigger bearing in the hub, meaning the hole size had to come down. So, later 16v or Series 3 cars had the smaller diameter / lesser teeth shaft.

 

[sprint_veloce]

As far as I know:

S2 1700 twin carb cars had vented discs and the bigger driveshafts (28 spline)
S3 1.7ie revert to the smaller driveshafts (25 spline) (and non vented discs right? I've never owned one)
S3 1.7 16V use the larger driveshafts and vented discs as fitted to S2 1700 twin carb.

 

[bobkelso]

Cheked on Eper, as Edward says
at 12 1989 they changed in the wheel hub the wheel bearing dimension and other related parties,
before the "millerighe" was D 30 x L 34,5 (28 spline I guess)
after the "millerighe" was D 27,5 x L 40 (25 spline?),
also the ring that retain the bearing in the hub and nut that retain the "millerighe" are different

Here some photos about someone already did the trick of the two meters bar,
the nut torque reported in the text is the "wrong" one (27 instead 40 of later 33 s3,
probably the author read it in the manual for 33 s1-s2) bur the tutorials I think is very good:

D?pose-repose d'une transmission

Remplacement d'un roulement de roue avant

Transmission

 

[edward]

I had a look a"millerighe" on google and it is splines, or spline shaft.

Eper is not working at the moment so will have to check later, but my understanding is that the series 3 cars has the smaller diameter (25 spline) drive shaft. There seem to be 2 different opinions as to what was used on the 1700 16v. I would have thought that Alfa would have stuck to one driveshaft / spline combination after they had decided to change. I can only imagine the 1700 i.e. and the 1700 16v being the same - surely?

 

[sprint_veloce]

Well it'd be good to get to the bottom of this. Maybe the 'larger' driveshaft for the 16V actually has a smaller spline where it fits to the hub? Counterintuitive, but possible.

 

[bobkelso]

Hi, yes probably what I copied from eper means that the new driveshaft end/tip,
with 25 splines, has the "millerighe/splines area" of smaller diameter (D=27,5 mm)
but longer (L=40mm) respect the previous one..
..I don't know about the driveshaft diameter itself and joint dimensions..

 

[edward]

Well, if the splines are the same size - but - the diameter is smaller - then you get less splines.

My thoughts are that the smaller diameter is 25 splines and in fact that checked out on a hub I have here. The difficulty is that I have no knowledge of what car it came from. The car was originally a series 3 with a 1300 and carbs!! So could be anything over the years, bearing in mind when I got it it had a 1700 16v. I need to see possibly an untouched 16v car and see what hubs it has, if I can be bothered. I would bet it has 25 spline hubs.

As you say - would be good to get to the bottom of.