On Sat, 17 Dec 2016 11:13:57 -0000, T i m wrote:

On Sat, 17 Dec 2016 01:49:11 -0000, "James Wilkinson Sword"
wrote:

snip

Sump plugs are usually the sort of thing with a very wide range of
acceptable torque. After all it's not holding things together. But
obviously relies on the correct sealing washer in good condition.

I didn't know until a friend told me recently that there was such a thing as an adjustable torque wrench,

You live and learn. ;-)

or any kind of numbers listed in manuals for the car for different torques for different bolts.

Yup.

Isn't it common sense how hard to push?

Nope, not to start with especially.

I suggested a mate replace the alternator on his Ford Galaxy himself
as from his description it sounded easily accessible and he was
willing to give it a go in the hope of saving a few quid.

He got it off ok but sheared one of the (perfectly good) retaining
bolts off when doing it all up through over tightening.

Just to show you can also go wrong *with* a torque wrench, another
mate decided to buy a VW camper and rebuilt it himself (as his first
ever real vehicle project). He did so on the understanding I'd try and
help him (even over the phone) whenever required.

He was rebuilding the engine and stripped one of the cylinder studs
out of the crankcase because he had mis-read the torque wrench.
Because all this was new to him he hadn't learned the feel of what
(say) 28 ft/lb was and so carried on turning till it stripped.

I don't think I would have 1) set the TR incorrectly or 2) carried on
past what I felt should have been around the right torque.

He had the damaged stud replaced by a local engineering co, finished
rebuilding the engine (that ran very smoothly) but the rest of it
(bodywork) was too much (too many other skills to learn, like welding)
so he sold it 'as is' (and made a bit).

I always have the problem REMOVING the bolts, as they're rusted on and you can't apply enough torque without damaging something.

--
You know you're getting old when:
Your friends compliment you on your new alligator shoes and you're barefoot.