|Air-cooled diesel engine powering a transfer pump.|
I remember one of Tracy's great posts, about the famous 271 Detroit diesel generators. The older two stroke Detroits were great, but they did have one problem: they weigh 2000 pounds or more. They can also be expensive because they are sought after.
At Drillcat we test many things for missionaries overseas. Missionaries and people living off the grid need a simple way to charge their batteries that is not expensive. The problem with gasoline generators is their higher fuel consumption. With gas prices the way they are, it costs $18.00 for a simple 5 gallon can of gas. Diesel generators have always been more efficient, the problem is that most of them are large and expensive. There are a few small, simple diesel engines available, and one of the most common is the Yanmar L100, 10 horsepower air cooled diesel engine. This is a reasonably affordable choice at approximately $1800 new There are also Chinese clones of the Yanmar L100 for around $600. These are a good choice for those on a budget. The 100% Yanmar air cooled diesel will run a full 8 hours on 1-1/4 gallons of diesel fuel. Amazing fuel pincher. We did test the china clone 10hp air cooled diesel engines. They burned 2 1/4 gallons per 8 hours which is still great. Some people are even putting this engine on motorcycles and getting 150 mpg.
The great thing about these air cooled diesel engines is that they are direct injection and have a very high compression ratio. They will start in below 0 weather also. Direct injection means you can actually burn other fuels besides diesel. We have successfully tested and run these engines on straight used motor oil (WMO). The used motor oil must first be filtered through a 10 micron filter. The filtering is only to remove the dirt and debris, and no other processes are needed to prepare the oil for use as fuel. In warm weather these engines will actually run on 100% WMO and even crank easily. In cold weather, you may have to mix diesel or kerosene to thin the oil enough to work properly.
Even though these engines are rated at 10 horsepower, they actually put out more horsepower than this. The horsepower ratings are purposely lowered to pass emission standards for the USA. We have successfully used these 10 horsepower rated engines to replace 15 and 18 horsepower power units.
To use one of these diesel engines to make your own generator, you can use a simple belt to drive an alternator for battery charging, a PMA (permanent magnet alternator), or a standard generator head. The same engine will also drive a transfer pump to salvage waste motor oil, which is how you get free fuel.
Many engines will run on vegetable oil, the problem is everywhere you ask for vegetable oil it is already taken. Used motor oil and hydraulic oil is the solution. Every mechanic shop or oil change shop is a place to get free fuel. These places of business are glad to get rid of the oil. The only thing you need is some way to remove the oil from their tanks. This is why we set up an engine to drive a transfer pump. These pumps transfer 25 gallons per minute or more. Our pump is a gear drive so it works great even in below zero weather.
These engines are not the only ones that will run on filtered WMO. The older Dodge trucks with the first generation Cummins 5.9l diesel engine had a higher pressure pump than the later ones. We have personally tested 1991 and 1992 year model Cummins trucks. They are direct injection and burn the waste motor oil very well; they don't even smoke any more than usual. They actually get 2 to 3 MPG better than regular diesel in fuel mileage. In cooler weather you will have to thin the oil with diesel or kerosene to prevent problems with the injection pump. In hot summer weather there's no problem.
One question that you may ask is, will it hurt the injection pump? So far we have not seen any problems with this. We do change fuel filters regularly. But look at it this way: to get an older 5.9 diesel injection pump rebuilt costs $600 to $800. At $4.00 per gallon diesel and $100 fill-ups, it wouldn't take long to pay for an injection pump rebuild even if you did have issues. Besides the way new EPA standards keep squeezing more and more things out of the fuel, the new diesel fuel is so dry without additives that it used to have, it is actually more dangerous to run than the used oil.
Try a test in your area, there may be hundreds of gallons of free used motor oil which equals free fuel or electricity in your area.
Master Well Driller
Water project Missionary Consultant
Hands on drill training Instructor
Author - Water Well Drilling Troubleshooting Guide
BTW, if you want one of the Yanmar clone engines Mark is talking about, you can get it here: small diesel and gas engines
This is the company I bought mine from back in 2007, so they are obviously in it for the long haul.