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Bob uk
Unregistered guest
Posted From: 94.197.122.74
Posted on Tuesday, 26 August, 2014 - 10:20:   Edit PostDelete PostView Post/Check IP

Everybody who has ever tightened a nut subconsciously thinks how tight. Critical stuff such as big end nuts brings the doubt and the worry.

So check again, which is how bolts get overtightened.

Clicking a torque wrench on nuts for a second time will tighten the nuts a bit more so I use a bendy arm torque wrench after to check.

One of my neighbours said he tightens wheel nuts until they make grauching noises. His dad told him it was right. He's a car recovery driver!!!?.

He is scared that a wheel will fall off a car he has worked on and get sued or worse.

Minis had a problem with steel wheels cracking between stud holes caused by overtightening.
The solution was to strengthen the wheel because people would most likely overtighten them even if you told them not to, due to the psychology of overtightening.

(Message approved by david_gore)
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Jan Forrest
Grand Master
Username: got_one

Post Number: 631
Registered: 1-2008
Posted on Tuesday, 26 August, 2014 - 18:52:   Edit PostDelete PostView Post/Check IP

I don't know when the practice started and/or ended, but using phosphor bronze wheel nuts (at least on Shadows) wasn't the brightest idea at the time. Considering the replacement cost and the fact that the ones on the left are left hand threads you have a recipe for disaster at too many tyre fitting places. It's likely worse in the US where they're taught as kids "Righty tighty, lefty loosey".

Fortunately, on average, the smaller the nut diameter, the shorter the spanner that fits. Unless you're a gorilla with a bad temper (or a tyre fitter with an air powered impact wrench) the length limits the torque to within reasonable levels.
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 1001
Registered: 6-2009
Posted on Tuesday, 26 August, 2014 - 23:40:   Edit PostDelete PostView Post/Check IP

Does anyone know the reasoning behind the phosphor bronze wheel nuts on SY cars? They've always struck me as not even a "solution in search of a problem" but just plain weird.

Although there were other manufacturers who used to use left hand threads on the left side this practice, too, seems to have been widely abandoned well before the introduction of the Shadow cars.

I always use a click type torque wrench when putting the lug nuts back on the car, as I could easily tighten them well above spec with just my own body weight and the supplied tool.

I've intentionally put small warning labels in the middle of all the wheels with the torque specs and about the left hand threads on the left. The small "Off ->" directional indication on the lug nut becomes very difficult to see over time unless you keep the upper surface on each relatively polished. The labels serve to remind me, but also the techs at my local tire fitter, who have been religious about using only hand tools on the lug nuts on this car.

Brian
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Bob uk
Unregistered guest
Posted From: 94.197.122.77
Posted on Wednesday, 27 August, 2014 - 05:38:   Edit PostDelete PostView Post/Check IP

Ford and others still use l/h wheel nuts on trucks.

phosphorus bronze is used because in cold weather the nuts fall off brass monkeys, so RR got them free.

In the UK All tyre shops use torque wrenches or torque extensions on windy guns. Which come in different colours for different torques. On the invoice will be a note to check nuts after 10 miles. And in the small print will be a get out clause it the wheel falls off after the 10 miles. ( meaning the nuts couldn't have been checked after ten miles)

Aluminum alloy wheels unlike steel wheels which spring in like a bell spring washer around the nut, need to be checked more due to no locking action from springing.

I don't see many loose steel wheel nuts but see a few aluminum alloy wheel nuts loose.
So torturing aluminum alloy wheels is a must, whereas steel wheels a educated nip up without a torque wrench is ok, they will still need a check after say 10 miles.

I have seen people drive with a knocking loose wheel until it falls off and they are generally t**ts.

(Message approved by david_gore)
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Jan Forrest
Grand Master
Username: got_one

Post Number: 635
Registered: 1-2008
Posted on Wednesday, 27 August, 2014 - 19:16:   Edit PostDelete PostView Post/Check IP

My 1980's (Rootes built) Dodge motor home has L/H threads on the left side of the vehicle. Mind you, the base chassis can go up to a plated rating of 7.5 tonnes.