Ahh, Torque, an un-assuming little beastie, it's always there and harms no one unless you abuse it, the stripped thread/broken bolt will have you rolling about in a fit of expletives.

What the hell is it and why is it so bloody important not to piss it off

Put simply (very) it's how tight a nut or bolt is and should be, not tight enough the bolt/nut might vibrate off or warp the thing it's holding together, too tight and it can warp the thing it's holding together or the bolt may snap or you'll strip the threads in a blind hole.

Either way it's problems which are easily avoided.

There are two ways to tighten a bolt/nut,

1 .put a socket wrench on and put a six foot scaffolding pole over the wrench handle, get the bolt/nut tight then jump up in the air and put all your wieght on the pole. You'll know when the process is complete by the bang, crash, snap noises as you fall on you're arse and the bolt snaps or the thread gives up and goes home.

2. Use a torque wrench to achieve the correct tightness,

Note : It's not always necessary to use a torque wrench, it depends how adept you are at judging tighness by hand, when fitting cylinder heads, cam bearing bolts, crank bearing bolts and other warpable/expensive if broken bits then it's a must. Disc bolts, caliper bolts, wheel spindles or you're heavy handed, it's a good idea to use a torque wrench if you're not sure.

First thing to do is buy a torque wrench from your local tool shop/mail order/Granny, the latter may not be much use since the torque wrenches used in knitting may not have high enough torque settings

There are many makes and size of torque wrench, often, the one's meant for cars just don't go low enough in the settings, i.e 10nm (newton metres, guess old Sir Isaac had problems wiv his bike), The table below show that 6nm is the minimum, so look for a torque wrench that goes from 0 to 150nm, you might not be able to get one with the whole range , I've got two, a wee one and a big 'un but some clever git's probably made one that does it all.

Here's a table of common torque settings, These are very general, the setting will depend on the material, whether it's a bolt, nut, tapped hole etc. If possible refer to your Haynes Manual or better still Workshop manual.

Nut (mm)	Bolt (mm)	General Torque Setting (Nm)
10	6	6
12	8	15
14	10	30
17	12	55
19	14	85
22	16	130

 

Happy Nut Work

McSpanners

 

 

 

Usually fixing a siezed caliper is pretty easy as long as ye catch it in time.

1. Remove the pads from the offensive (usually highly if this job is necessary) caliper.
2. Remove the rubber dust seals from around the piston (if there not there than it's probably why yer off swearin' in the garage, go order some if ye haven't got them.
3. Unbolt the caliper from it's mounting.
4. BEFORE disconnecting the brake pipe, pump the brake pedal/lever/chocolate doughnut (delete where applicable) until the piston/s pop out, good idea to put a rag down (yer mum might get annoyed if ye ruin her nice new Axminster wiv all the brake fluid)
5. Check the seal around the piston, if ye were leakin' brake fluid see a doctor immediately, but if the caliper woz leakin' then it's a good idea to replace them.
6. Clean all the shite off with a suitable cleaner, Solvol or something like it. If it's shite of the caked on variety then a scraper can be made from a bit of copper or ally, NOT steel coz it'll score the piston.
7. Now that it's nice and shiny put the fluid seal back on, the new one if it needed it.
8. Put the piston back into the caliper, smear a bit of brake fluid round the piston for lubrication if necessary, make sure it's squared up tae the hole, use a G clamp to push it home.
9. If the piston is reeeaaallyy rusty then a new one is normally in orser, depends whether it's rusty within the area of travel.
10. Fit the dust seals, put yer pads in, bolt it up and bleed the brakes, wahey, no more hassle for at least another 2 months (if ye live in Scotland and drive in the winter)

And that's that ! Good Luck.