Gel point is vastly different for #2 diesel and vegetable oil -- #2
has a pour point as low as -30F, and I doubt veggie oil, particularly
used veggie oil, will be fluid enough to pour at 10 F, let along
-30. Not all #2 has a pour point that low, but it can.
There are two larger problems, fhe first of which is viscosity.
Vegetable oil is much more viscous than diesel oil, and I strongly
doubt it will flow well enough below say 50F to start the engine.
Certainly at 0F, most of it will be frozen solid, or pour like cold
molassas, and no start.
Second, it produces both varnish and hard ash, since it contains
phopholipids and is a tricarboxylic acid ester of glycerol. All
that oxygen results in oxidative hardening, accelerated by heat, so
you are going to gum up all the operating parts. The hard ash will
score the pintles in the injectors, causing operational problems, and
can damage rings, too.
This is to say nothing of the presence of trace amounts of protein
and carbohydrates from being used for cooking, along with various
cracking, hydrocracking, and oxidation products and other food
residue. All of this goes away when you make biodiesel (which has
it's own problems).
Poor combustion, for whatever reason, will result in gummed up rings,
stuck lifters, and hard sludge in bad places, this is just the nature
of vegetable oil.
Veggie oil also has different lubricity than diesel fuel, and may
cause serious lack of lubrication problems -- I'm not sure of that,
but it is definitely different.
Water in the tank will instantly grow masses of slime -- veggie oil
in the presence of water is a food feast for multiple
micro=organisms, and you will have a mess very, very quickly once you
get some condensation in the tank (the first day after you fill it,
most likely). Diesel fuel is toxic to most of the bugs, but veggie
oil is pure food. Plugged filters are a chronic problem, and can
happen suddenly.
Mixtures work better than pure waste oil, and in order to actually
reliably operate the car safely, you must start and stop on diesel
fuel and heat the veggie oil until it has the same viscosity as
diesel fuel. Otherwiise, you may end up fuel starved and deeply
inconvenient times, such as when merging into heavy traffic. Mad
mojo, having the car quit suddenly then.
Peter, who puts waste oil in his car once in a while, but will never
try to run on pure veg oil.
_______________________________________
http://www.okiebenz.com
For new and used parts go to www.okiebenz.com
To search list archives http://www.okiebenz.com/archive/
To Unsubscribe or change delivery options go to:
http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
