[Vwdiesel] Diesel working on liquid propane

[Roger Brown]

On 10/12/2010 1:06 PM, Doyt W. Echelberger wrote:
> Getting it to burn is the name of the game.
>
> Hoover used forklift hardware to turn the liquid propane into gaseous fuel.
> Large problem was icing up of the carburetor. Then he had to find places
> for the propane tanks. The propane burned so cleanly that the oil never got
> dirty. He figured that using propane would roughly double the engine's
> service life and greatly decrease maintenance costs.
> "Gasoline is a solvent. It washes the lubricant off your valve stems and
> cylinder walls. When it burns it generates a number of by-products that
> reduce the life of your engine by altering the chemical composition of your
> lubricating oil. Gasoline atomizes into a vapor, not a gas, and even then
> imperfectly. In manifolding of any length there is some degree of
> stratification in the fuel/air mixture and the combustion process itself is
> imperfect, prone to destructive detonation when any one of a host of
> variables is changed. Gaseous fuels do none of these things. Running on
> propane, your oil looks green and new after ten thousand miles (assuming
> you've got shaft seals). Valve-guide and cylinder-wall wear is markedly
> reduced on engines burning gaseous fuels and with an octane rating of over
> 100 detonation is seldom a problem. The bottom line is that when you get
> rid of the gasoline you extend the life of your engine."  Bob Hoover, 1997.
>
> He was about 15 years ahead of his time.
>
> Doyt

My dad has been running his '70 Chevy pickup on LPG since '73 and it is still going 
strong, original gasoline engine and all.  I recall about 10 years ago, the engine finally 
broke the OEM timing chain.  When they tore down the engine to replace that, they 
inspected the pistons, rings and bores and all were in such good shape, they just put a 
new chain on it and called it good.  I think it is well over 750K miles by now.

I remember when I was still living at home while going to college, I often thought to 
putting the drained oil out of the Chevy into my gas VW Rabbit that I owned at the time. 
It was so clean that you could not tell it from new oil.  I also used to run an old Toyota 
Landcruiser on propane about 20 years ago and on that engine, I never changed the oil.  It 
leaked enough that in about a year, I figured the oil changed itself and it never showed 
any change in color, in fact it was hard to see on the dipstick.

For diesel, LPG injection used to be called "fumigation".  Might try searching for that. 
Typically only of benefit on turbo engines, you use the LPG to burn with the excess oxygen 
in the cylinders.
	
-- 

   Roger