Calliper halves for 8.4" discs (torque wrench setting)

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

John Reinders - 11 Nov 2003 17:43 GMT

I bought a second hand set of 8.4" disc brakes / hubs / driveshafts and
cleaned everything, including the callipers, in paraffin.
The Haynes Book says not to use petrol-based liquids but methylated spirit
or brake fluid and I think I know why.

If paraffin is used, the rubber washer between the calliper halves becomes
unusable, so i need to take the halves apart to fit a new one.
But when it comes to fitting the halves together again there is no book in
which I can find the torque wrench setting.

Any idea?

Thanks,

John

Reply to this Message

Makka - 12 Nov 2003 11:43 GMT

real tight ???
makka

> I bought a second hand set of 8.4" disc brakes / hubs / driveshafts and
> cleaned everything, including the callipers, in paraffin.
[quoted text clipped - 11 lines]
>
> John

Reply to this Message

Kelley Mascher - 12 Nov 2003 16:55 GMT

I've never seen a spec. for these bolts either. Look at the "Fastener
Torque Recommendations" at the URL below.

http://www.arp-bolts.com/pages/tech/tech.html

My guess is, the bolts on a brake caliper are higher than normal
tensile strength so I would look at the 190,000 psi column. You will
need to lubricate the threads and obviously oil is a bad thing in this
application. Graphite might work or a dry Moly lubricant.

Good luck,

Kelley

>real tight ???
>makka
[quoted text clipped - 13 lines]
>>
>> John

Reply to this Message

ops - 14 Nov 2003 00:09 GMT

> I bought a second hand set of 8.4" disc brakes / hubs / driveshafts and
> cleaned everything, including the callipers, in paraffin.
[quoted text clipped - 7 lines]
>
> Any idea?

Yes and as the good book says 35.5 to 37 ft lbs (4.9-5.1 Kg M)

You can always make an approximation of the torque setting as bolts are
marked in accordance of tensile strength and you can measure the diameter.

> Thanks,
>
> John

Reply to this Message

John Reinders - 14 Nov 2003 19:54 GMT

> > I bought a second hand set of 8.4" disc brakes / hubs / driveshafts and
> > cleaned everything, including the callipers, in paraffin.
[quoted text clipped - 12 lines]
> You can always make an approximation of the torque setting as bolts are
> marked in accordance of tensile strength and you can measure the diameter.

In the meantime I found out that loosening the bolts with a torque wrench
gives an indication.

I foud 4 times (4 bolts) 5.0 KgM (50 Nm) which is the same as Martins book
says!

Wonderful, such a newsgroup!

Thanks ops (Martin?).

Reply to this Message