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4.6 Crank?

Posted: Sat Apr 07, 2012 6:26 pm
by ikari1
Hiya

I've got a 4.6 crank and rods coming so I can turn my 4.0 P38 Range Rover into a 4.6. I don't know the history on the crank except it's from a 1998 P38. Can anyone tell me what the main and big end measurments should be presuming it hasn't been previously ground? I'm planning a 10 thou grind so I'm building it from a known tolerance but I'm wondering what the starting point is.

Many thanks.

Posted: Sun Apr 08, 2012 8:03 am
by ChrisJC
Image

From the Land Rover Workshop Manual.

Chris.

Posted: Sun Apr 08, 2012 10:32 am
by ikari1
Thanks for that. Am I wright thinking the "Minimum regrind diameter" is the diameter at which you need to use the -10thou bearing shells?

Posted: Sun Apr 08, 2012 12:15 pm
by DEVONMAN
ikari1 wrote:Thanks for that. Am I wright thinking the "Minimum regrind diameter" is the diameter at which you need to use the -10thou bearing shells?
There may be a typo in the numbers as the minimum regrind for the main journal is quoted as larger than the original size ???

The minimum regrind size is what Rover considers to be safe, or the size of available bearings that Rover produce/stock when their W/manual was published.

It is now possible to get bearings up to 60 thou from standard.
Ok, at this size the crank is slightly weaker but still much stronger than say a 3.9 crank.

Regards Denis

Posted: Sun Apr 08, 2012 2:38 pm
by kokkolanpoika
I always wonder those measurement´s..
Check millimeters and inches..
Excample main bearing 63.487-63.500mm is not an 2.499-2.52"
2.499"=63.474mm and 2.52" = 64.008mm 0.5mm clearnace is quite big.. :D
Quality for Land Rover translator..
I say that those mm readings are correct..