Jean-Pierre Labuschagne wrote:
>
> For what it is worth the original MGA workshop manual they say the
> following with regard to wheel nuts "Tighten the nuts to a torque wrench
> reading of 60 to 62,5 lb. ft (8,3 to 8,65 kg. m.). Do not overtighten."
> I do wonder would these settings change over the years due wear and tear on
> the bolts?
> And lastly the front end wheel clunk experienced on my MGA was due to the
> break shoes being incorrectly fitted and adjusted.
>
> '57 MGA 1500
> Safety Fast
The fastener industry is highly misunderstood by many in our hobby.
What is of concern in any bolted joint is clamp force. Since there is
no non-intrusive means to measure clamp force in the field, studies are
done in the lab using special sensors to determine what clamp force is
acheived with a given torque. These are the numbers that we see in our
manuals. What is not addressed is whether this torque is acheived with
a dry bolt, a dry lubricated bolt, or a wet lubricated bolt. A
lubricated bolt, tighted to "X" foot pounds will acheive a much higher
clamp force that a dry bolt at the same torque - due to differences in
the frictional coefficient between nut and fastener. Does anyone have
information on the type of lubrication (or lack thereof) was intended
when the manuals were written?
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