At 02:13 PM 3/8/2011, Scott Daniel  - Turbovans wrote:
>it is a 12mm thread diameter bolt.
>
>a 19mm hex head is a very normal size bolt head for a 12mm thread bolt.
>
>It's a rather fine thread and is about the only spot in a waterboxer
>vanagon where you will find this fine  12mm thread.

Ok, Scott's right.  It's an M12x1.5, 35mm long.  That's the M-series
fine thread for 12 mm and in the DIN (Deutsche Industrie Norm)
standard that will have a 19 mm head.  In the ISO (International
Standards Organization) series it will have an 18 mm head and in the
JIS (Japan Industrial Standard) it will be a 17 mm head.  I suspect
if you buy one at NAPA it will probably be ISO series.

My 16 mm head turns out be a 7/16-14 grade 5 bolt with the usual 5/8"
head.  I don't even want to think about how that got there.  It might
thread into a 12x1.75 mm hole but I don't see a chance of it fitting
a 12x1.5, so someone's been in there with a tap.  Gah.

Yours,
David