Driveshaft End Nut

[Guest Colin45]

Hi all,

 

I have just replaced the lower engine mount and had to remove the driveshaft (that was fun!) and when I came to putting the nut back which holds the driveshaft into the wheel bearing assembly I looked at the torque setting in the haynes manual.

 

The figure quoted is approx 118 lb/ft.

 

My torque wrench doesn't go over a hundted, is the quoted figure wrong or do I need to but a new torque wrench.

 

Cheers

 

Colin

[EdCherry 34 1 Cars]

You need a different torque wrench with a higher scale.

[Cameron 16]

You should try the rear ones, 180Nm or something like that..

 

Yeah you'll need a more manly torque wrench.

[lagonda 42]

Do it yourself torque wrench.....socket, T-bar & pipe over T-bar. Arrange pipe so that it's 2 feet from tip to socket centre. Then....get some bathroom scales & a small piece of wood. To start, use your torque wrench & tighten nut to maximum setting on that...then you are part way there. Now use the T-bar & pipe, arrange the tip of the pipe against the block of wood, against the centre of the scales pressure pad.....obviously you need to organise things so that you can read the dial on the scales. If your pipe length is 2 feet, push until you see 59 lbs...then you have 118lb/ft. It sounds unwieldy but it really does work. Think about it...you are applying 59lbs of pressure against a leverage of 2 feet. You could of course try 1 foot of pipe & apply 118lbs pressure, but that would be hard work. I now use a breaker bar & work the maths out from the length of that...one thing you need to watch is that you're not bending your T-bar, which it might, if it's a cheap one....because not only will you have bent the T-bar, but also your "reading" will be incorrect as part of your torque will have been spent bending the bar.

[mr_exe 1]

Sounds easier to use a proper torque wrench! Can you borrow one instead of buying another?

[omega 82]

Do it yourself torque wrench.....socket, T-bar & pipe over T-bar. Arrange pipe so that it's 2 feet from tip to socket centre. Then....get some bathroom scales & a small piece of wood. To start, use your torque wrench & tighten nut to maximum setting on that...then you are part way there. Now use the T-bar & pipe, arrange the tip of the pipe against the block of wood, against the centre of the scales pressure pad.....obviously you need to organise things so that you can read the dial on the scales. If your pipe length is 2 feet, push until you see 59 lbs...then you have 118lb/ft. It sounds unwieldy but it really does work. Think about it...you are applying 59lbs of pressure against a leverage of 2 feet. You could of course try 1 foot of pipe & apply 118lbs pressure, but that would be hard work. I now use a breaker bar & work the maths out from the length of that...one thing you need to watch is that you're not bending your T-bar, which it might, if it's a cheap one....because not only will you have bent the T-bar, but also your "reading" will be incorrect as part of your torque will have been spent bending the bar.

 

 

Sounds easier to use a proper torque wrench! Can you borrow one instead of buying another?

 

come on give the man some credit this is a FANTASTIC solution[if its right]

[B1ack_Mi16 67]

come on give the man some credit this is a FANTASTIC solution[if its right]

 

Sure it sounds correct, however I find myself just tightening those hub nuts by the feeling.

 

Just get a pipe to put outside your breaker bar and then apply good leverage.

 

Torque = Force * Arm so if you wanna do it properly get a arm with the correct length so that when the force matches your body weight the torque will be correct.

 

Anyway just torque it up properly, I've never had any problems with that

[Guest Colin45]

Sure it sounds correct, however I find myself just tightening those hub nuts by the feeling.

 

Just get a pipe to put outside your breaker bar and then apply good leverage.

 

Torque = Force * Arm so if you wanna do it properly get a arm with the correct length so that when the force matches your body weight the torque will be correct.

 

Anyway just torque it up properly, I've never had any problems with that

 

I just did it as tight as I could with the long bar torque wrench and hope for the best.

 

Cheers for the comments (as radical as they were!).

 

Colin

[pug_ham 245 3 Cars]

The figure quoted is approx 118 lb/ft.

That figure is wrong, what section did you read that from?

 

Haynes states its 185lbft for Non GTI models & 192lbft for GTI's. (Chapter 7; driveshafts)

 

Graham.

[dcc 855]

I was thinking, when i did mine i used about 190, and even then i thought it should have been more... isnt the crank bolt something massive too.

[pug_ham 245 3 Cars]

isnt the crank bolt something massive too.

Surprisingly not @ 80lbft but its an important figure to get right if the crank does run the oil pump cog through a woodruff key because if it isn't tight enough or comes loose the eengine looses oil pressure with dramatic results.

 

Graham.

[Tom Fenton 1,548]

Surprisingly not @ 80lbft but its an important figure to get right if the crank does NOT run the oil pump cog through a woodruff key

 

Added an important word for you Graham!

 

For some reason 1600 engines seem to have the key fitted, whereas 1900 engines do not.

[pug_ham 245 3 Cars]

Added an important word for you Graham!

 

For some reason 1600 engines seem to have the key fitted, whereas 1900 engines do not.

 

Thanks Tom.

 

Its a bit hit & miss with the 1900 lumps imo, all three I've stripped have had the woodruff key but only one of those was a 205 1900 lump with the other two being a 405 SRi & BX GTI lump.

 

I used the crank out of the BX engine in mine so it has the woodruff key even with the crank bolt done up to the correct torque & with a dab of locktite on.

 

Graham.

[matthewm 1]

On the drive shaft torque figures, I've only ever just given them a good tweak with a power bar, on the basis that the locking pin and collar holds it in tightly. Never had a problem in the last 5years on my rally car with this, is there something I'm missing to how vital it is to be this tight?

Edited February 18, 2010 by matthewm

[welshpug 1,666]

if its not tight enough you risk having the wheel bearing moving around on the hub flange, and too tight you risk either wearing the bearing prematurely or snapping the end off the CV (it has been known to happen on re-manufactured shafts!)

 

obviously those are in extreme cases, seeing how little a decent torque wrench costs and the other fasteners that you really should use it on its a good investment.

 

wheel bolts, wheel bearings, wishbone bolts and balljoint nuts are items that I always use a torque wrench on.

[Anthony 1,003]

On the drive shaft torque figures, I've only ever just given them a good tweak with a power bar, on the basis that the locking pin and collar holds it in tightly. Never had a problem in the last 5years on my rally car with this, is there something I'm missing to how vital it is to be this tight?

In the case of driveshaft nuts, in my opinion it's fine and like you, I've had no problems whatsoever in years doing the same thing.

 

There are plenty of parts on the car where torquing something up properly is critical, but for alot of things, simply "nipped-up", "tight" or "FT" suffice perfectly well.

[matthewm 1]

I'll give them a tweak with my torque wrench out of curiosity then, see how far out my estimated tightness is!