Hi Everyone...I am really open to all suggestions anyone can offer about 300TD wagons years '80-'87...I hope to eventually convert the engine to run on alternative fuel sources.
Its my understanding that you actually convert the fuel, not the engine.
You see, Rudolph Diesel, the inventor of the engine from whom the engine takes its name, didn't design his engine to run on Petroleum-based products, but rather, on Peanut Oil
In those days, petroleum based oils, such as Gasoline, weren't very common and he wanted to design something that would run on an easily obtainable fuel source...so why not something that could be found in most kitchens?
You could even run the engine on whale oil, which was a common fuel of the time (for lamps).
The engine was actually modified so that it would run better on petroleum based oils, later on in its development, since the otto-mobile
was becoming somewhat of a world wide sensation.
Thus, going back to cooking oil, as an alternative fuel source, isn't really that much of a stretch for a diesel engine.
The only problem is that the sugars present in most cooking oils can foul the injector and injector pump, which is literally the beating heart of the Diesel engine, thus one must remove those sugars, in order to be able to use the oil on anything approaching a permanent basis.
There is (or used to be, anyway) a large "still" that one could buy, that would remove those sugars (and other impurities) from used cooking oil.
It was quite effective, although the $2500 selling price (minus shipping, handling and any taxes that may apply) might be a bit steep for some.
Wanna see the process in action?
Check Youtube, or maybe Discovery's website, for the first episode of a show called "Dirty Jobs".
Mike Rowe's very first, ever, "Dirty Job" was to convert used cooking oil into a fuel that could be burned in a diesel engine.
The still that guy uses is the one I'm referring to here.
Stacey David also did a feature on it, on that "Trucks" show he used to do on TNN (or whatever they call it now), a few years ago.
However, you can use cooking oil, straight out of the bottle (or pan) in your car and it'll burn just fine.
I would NOT recommend long term usage like that, but in a pinch, it just might help you get home.
Just remember to filter the stuff as you pour it in.
They proved that on Mythbusters, when they took used cooling oil, and sifted it through several large coffee filters and straight into a bottle which was fitted to the fuel line (doing a milage test to see if one could actually run a diesel powered car on used cooking oil - and of course, the guinea pig was a 300D
Granted, they only used one measured gallon, but the car did run, although milage was down slightly.
But getting back on subject, the point of this (now) overly long reply is that one doesn't refit the engine to run on the cooking oil. One "refits" the oil, so that it can be safely used in the engine.
...and yet, there's still some concerns about lubrication (the fuel actually lubrcates the injection pump and injectors), so you still might want to blend in some actual "diesel fuel" (maybe 5-10%, by volume), so a fuel blender wouldn't be a bad investment, either.
It might seem a bit "poo-poo" to incorporate the very thing you're trying to eliminate, but look at it from the other side, you're still eliminating about 90-95% of the thing you're trying to get rid of.
Anyway, hope you found this information to be of use.