When I worked for Nissan I saw a few VG30 (most were not T or TT) motors
shear the end of the crankshaft. This was caused by the radius at the
nose of the crankshaft being too sharp, causing a stress riser at that
point. Nissan subsequently redsigned the crankshaft.
Jim Moore
69 2L RHD
Germantown MD
Thomas Walter wrote:
> Richard,
>
> Of general interest, I stopped by my local metal scrap yard
> yesterday. I am always looking for 6061-T6 end pieces.
>
> In the process of scouting the yard, was a VG30T engine
> sitting there. Hmm, the end of the crankshaft failed in
> shear! Wish I had a magnifying glass, as I was curious
> to see the root failure, but it was a one time overload.
> Hmm, wonder if someone tried out a 50 psi turbo!
>
> Oh, of the failure, only reason I could see, with the
> naked eye, was the failure started at the oil passage
> hole to the last bearing. Shear was at a 45 degree
> to the crankshaft plane. Interesting to observe.
>
> When I was at Cal Poly (California Polytechnic - San Luis
> Obispo) I enjoyed playing in the metals lab. Lots of
> fun stuff. Wouldn't mind a hardness tester at home to
> check out those bolts!
>
> HEY FOLKS - The upper bolts are 7/16-20tpi. The AN7 just
> means a 7/16" bolt. I do not recall the length needed,
> but would recommend double nutting the bolts. Yep, had
> a 'clunk, clunk' on the front end... shims had fallen
> out! Loose bolt.
>
> Cheers,
>
> Tom Walter '67 2000
> Austin, TX '68 2000
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