Disc Brake Castle Nut Torque Spec Confusion
Best Answer Spider , 01 July 2019 - 09:38 PM
There was a change in CV spec (I can't recall when, I think 86?).
The early Disc Brake type CVs had 2 holes for the split pin and the correct torque for these is 150 ft / lb then further tighten around to the next slot.
The latest spec CVs, identifiable by a single hole for the split pin is 197 ft / lb then tighten further to the next slot.
The change came about to reduce chaffing of the wheel bearing (inner) cones and the spacer.
Go to the full post#1
Posted 01 July 2019 - 08:12 PM
I'm very confused about something.
I have a few different workshop manuals. I have a Haynes workshop manual '69 to '88, an intereurope workshop manual 148, and another one.
All three books state the castle nut torque spec on Cooper/ Cooper S/ GT (as in disc brake models) as 150 lbft or 207 Nm.
I used this torque spec everytime I've had to torque up the disc brake hubs. I assumed this is correct as it's what the books say and they all match each other.
Recently when checking the forum I kept reading this thing that says 150 lbft (207 Nm) is for CV joints with multiple holes and 255 Nm is for CV joints with a single hole.
I can't find a source for this new information and is it because the earlier books were incorrect? Or did something change on Minis? Were early CV joints all multiple hole items?
I'm actually getting kind of worried. The standard recommendation has always been to get a Haynes manual that covers your specific model in a lot of depth (so a manual with spi and mpi stuff surely shouldn't be needed?).
Yet here I am having possibly driven a Mini with the wrong torque spec on something so safety critical. The Mini is parked up for now, and I'm not going to move it until I'm sure it's safe to do so.
Any help would be greatly appreciated. I'm at a loss as to what I'm missing.
Regards,
Vinay
#2
Posted 01 July 2019 - 08:24 PM
I use this on my own minis, I've never had any issues
#3
Posted 01 July 2019 - 09:38 PM Best Answer
There was a change in CV spec (I can't recall when, I think 86?).
The early Disc Brake type CVs had 2 holes for the split pin and the correct torque for these is 150 ft / lb then further tighten around to the next slot.
The latest spec CVs, identifiable by a single hole for the split pin is 197 ft / lb then tighten further to the next slot.
The change came about to reduce chaffing of the wheel bearing (inner) cones and the spacer.
#4
Posted 01 July 2019 - 10:11 PM
I just do it up 'ET'. Seems to work OK.
Edited by Moke Spider, 02 July 2019 - 05:47 AM.
#5
Posted 02 July 2019 - 03:28 AM
200nm then next hole is more than adequate
I use this on my own minis, I've never had any issues
That's strange. I wonder whether there's a long term effect.
There was a change in CV spec (I can't recall when, I think 86?).
The early Disc Brake type CVs had 2 holes for the split pin and the correct torque for these is 150 ft / lb then further tighten around to the next slot.
The latest spec CVs, identifiable by a single hole for the split pin is 197 ft / lb then tighten further to the next slot.
The change came about to reduce chaffing of the wheel bearing (inner) cones and the spacer.
Thanks, Chris. It's a bit annoying that the spec changed making the old book information incorrect, but at least now I know. I'll get a more substantial torque wrench and tighten them up correctly. The CV joints i have are the single hole ones.
I just do it up 'ET'. Seems to work OK.
I'm not sure what ‛ET' means?
Edited by Moke Spider, 02 July 2019 - 05:48 AM.
#6
Posted 02 July 2019 - 05:14 AM
I just do it up 'ET'. Seems to work OK.
I'm not sure what ‛ET' means?
Second word is 'tight'...
Edited by Moke Spider, 02 July 2019 - 05:48 AM.
#7
Posted 02 July 2019 - 05:49 AM
I just do it up 'ET'. Seems to work OK.
I'm not sure what ‛ET' means?
I'd guess 'Extra Tight' ?
#8
Posted 02 July 2019 - 08:04 AM
I just do it up 'ET'. Seems to work OK.
I'm not sure what ‛ET' means?
I'd guess 'Extra Tight' ?
I see you edited all the posts, Chris! To be fair, I thought it might be 'fully tight'
Edited by Vinay-RS, 02 July 2019 - 08:07 AM.
#9
Posted 02 July 2019 - 08:54 AM
in terms of "on to the next hole" that can be a fair distance especially on the single hole CV, I used to keep a stock of nuts and conical washers, and mix and match to get things closer, I think its worth knocking the conical washer face and nut face where they met back with a bit of wet and dry or wet stone to get them smooth too, and on ocasion ive taken a bit off the back of the nut when the holes have been a mile off.
#10
Posted 02 July 2019 - 10:27 AM
Of course I could have used the other expression FT, but I thought that might be a bit rude!
#11
Posted 02 July 2019 - 11:39 AM
I assumed it was "effing tight"
#12
Posted 02 July 2019 - 11:40 AM
No - enough tight -
#13
Posted 02 July 2019 - 12:02 PM
#14
Posted 02 July 2019 - 12:10 PM
Imagine being the poor guy who made the workshop manual and wrote all the torque specs down.
I mean, that was my question, Since the spec seemed to change from earlier books to later ones and I was a little curious as to why.
I'm not the biggest or strongest person and to be honest, I have found that if I tighten a nut or bolt on the car such that it is tight for me, someone can usually come along and tighten it further. Hence, I try to stick to the book torque specs. Putting numbers to things makes it less likely that I'll have made a mistake. It's especially useful if, like me, one is a noob at mechanics
#15
Posted 02 July 2019 - 12:34 PM
Never had any issue with the settings as I just looked for the info as it was different.
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