[Vwdiesel] Candles? Was: Topic limited, or people enabled? And Wheel Bearings.

James Hansen jhsg at sasktel.net
Mon Oct 3 17:20:16 EDT 2005

Ground up candles?  Why?

I've never really understood the multi-viscosity -vs- straight weight
issues...my education is somewhat lacking.

And generally the rants are entertaining and usually informative.


Paraffin wax is basically long chain fuel.  too long a carbon chain to
remain liquid at room temperature.  dissolving it in diesel increases the
lubricating properties of the fuel, and gives it more C=C bonds to break,
therefore more power for a given weight. However, the paraffin will
precipitate at lower temps, so this is best done in summer.  Keep the
candles in the car for emergencies in winter.

In a nutshell, viscosity improvers don't lubricate well.  Multigrade oils
that are 0 W- or 5W-  need a lot of improvers to keep them from having the
viscosity of apple juice at operating temperature, because the first number
tells you what the cold viscosity is, hence how light the oil base stock is
to start with... so, multigrade with a big gap between numbers has less
percentage of oil, more percentage of additives that don't lubricate quite
like oil.
Straight grade oils are that grade or viscosity to start with, the base
stock is what is responsible for their properties, not additives for the
most part.

In use, when new, they tend to act the same, but as the viscosity improvers
wear, the oil tends to return to it's base stock state, and lose it's hot
viscosity and lubricity at operating temps.  Multigrade synthetics are a
good way to address some of this aspect of oil wear, but tend to the pricey

If you change your oil like you are supposed to, this is not a factor in the
slightest and is all interesting theory.  There are some applications for
straight grade oils, such as the 2 cycle detroits require straight grade 30,
and I know Shell keeps it in their line specifically for that.  A lot of
older construction equipment specs straight grade engine oil in their
hydraulic systems as well, probably for the convenience aspect at the time

The damage you can do to crankshaft bearings by forgetting to change your
straight grade oil when it gets cold far outweighs the benefits that may be
there in running the straight grade oil in the long run.

No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.344 / Virus Database: 267.11.9/116 - Release Date: 9/30/2005

More information about the Vwdiesel mailing list