Fantastic idea.

19mm = .748"
3/4" = .750"

The engine will never know the difference and neither will you.

If you can fit a 3/4 inch allen inthe socket, then use it. 19 mm is .748 inches, so 3/4 inch is slightly bigger. Always go for the snugger fit.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Like minds...............

Yep 19mm...OR!!!! 1/2 inch bolt head
If you have a welder and some goodies handy you can make yourself a really nice allen wrench setup

I cheated and used some pretty serious heat (and force) to get it out though.

Also...don't use the pipe wrench. Only about 1/16-1/8th inch of plug stucks out..and its rounded..
I think attacking the edge with a pipe wrench would just reak havock on the plug.
Also it would be nearly impossible as you would ahve to right parallel with the side of the block to get a good bite.

I'd go with the head/cold myself
And just so you know
on a turbo engine
it sure looks a LOT easier to pull the manifolds/turbo setup than pull the starter and still not have enough room..
espically if you plan on using some fire
:fork_off: