On 20 Nov 2006 18:06:19 -0800, "Skip Gundlach"
wrote:

If there are engineering reasons against, due to the nature of the
waste oil, are there any levels of change (more frequent) which would
mitigate those, assuming that filter changes occurred at the same
intervals?

I know it's useless to ask :{)) but it would be more informative to
have sound engineering rather than conjecture in reply to this topic...

Recycling crankcase oil as diesel fuel is quite common among large
fleet users, and there is actually some engineering information on the
web. I know people with a Skookum 53 long range cruiser where the
recycling system is actually built into the boat. Racor makes a
system to do this but it is too expensive for recreational boaters in
my opinion, about $2000 if memory is correct. To make a long story
short, the oil to be recycled should be passed through a filter and
then blended with diesel at a 20 to one ratio, i.e., 20 gallons of
diesel to one gallon of used oil.

http://p2library.nfesc.navy.mil/P2_O...ook/6_I_2.html

http://www.awma.org/journal/pdfs/1999/1/ray.pdf