On 16/02/13 22:37, wrote:
On Sat, 16 Feb 2013 22:36:19 +0100, Uffe Bærentsen
wrote:

Den 16-02-2013 18:35, skrev:
On Sat, 16 Feb 2013 15:15:43 +0100, Uffe Bærentsen
wrote:

Den 16-02-2013 07:11, skrev:

Sounds like you have seen most of what a car can throw at you.
And those are just the highlights of the last 46 years. - and not
including any of the customer vehicle issues in my life in the trade
(about 25 years) in Canada -----
Saw one funny thing on some Chevy's a while back (1995/1996).
We were told they were built in Canada and that was the reason for the
all out metric tooling and threads on those.
Gave us a hard time since all our tooling was imperial.
Do you know if that could be true?

It was this model

http://www.easyautosales.com/used-ca...-84353930.html

only line trucks with toolboxes on the side of the bed.
Made in Oshawa Ontario. Vehicles of that vintage were *******ized
metric. Some parts were imperial - because they came from the USA.
Some were metric - but not metric standard. For example, in place of
5/16" bolts they used 8mm - but 8mm SHOULD have 12 mm heads - they
used 13 because it was "close enough" to 1/2" that 1/2" wrenches would
"sorta" fit. Same with 1/4". Replaced with 6mm - which should have
10mm heads - but they used 11mm because a 7/16" wrench would "sorta"
fit. So some redneck shadetree mechanic would try to force a 1/4 unf
or 5/16 unf bolt into the hole, or nut onto the stud, and bad things
started happening real fast. Not bad on a new vehicle where the
"metric" bolts had a green colour to them - but after about 5
years?????
Was stuck with several of those *******s in a location were it was
difficult to get supplies. A 1/2" was simply not allowed if it should be
a 13mm. Rather park the vehicle for the time it took to get the right
spanner.
Standard sizes on spanners for metrical nuts a (thread/spanner)
6mm/10mm 8mm/13mm 10mm/17mm 12mm/19mm
So my guess would be that they used 12mm heads.
You have it mixed up. Standard on an 8 is 12, everywhere in the world
except north america.
I must have been buying US metric bolts then for the last 20+ years in
the UK as all the M8 hex fasteners I buy have 13mm AF heads. See

http://www.fairburyfastener.com/xdims_metric_nuts.htm
http://en.wikipedia.org/wiki/Screw#I...c_screw_thread
http://www.roymech.co.uk/Useful_Tabl...Hex_Screws.htm
http://www.bath.ac.uk/idmrc/themes/p.../bol/bol7.html