The fuel system on a diesel engine is a highly specialized set of components which…
Crude Oil Fuel
Note: Crude oils are not suitable for use as fuel in all engine applications.
The suitability of these fuels for use is determined on a case-by-case basis. A complete fuel analysis is required.
NOTICE: Use of permissible crude oil fuels can result in higher maintenance costs and in reduced engine service life.
NOTICE: Caterpillar does not recommend using any of the heavier fractions such as residuals or bottoms in engines that are configured to use distillate diesel fuel. Failure to follow this recommendation will result in severe wear of components and engine failure.
Residual fuels or blended fuels with residuals are unsuitable because they have a high viscosity range, low ignition quality and high vanadium and sodium contents that shorten engine life. Such fuels may cause high wear rates in the fuel system, on the piston rings, cylinder liners, and exhaust valves. Also, filter problems and deposits in the piston ring belt may be evidenced.
Special crude oil fuel pretreatment equipment may be required and is available from suppliers of fuel treatment equipment. Also, it may be essential to start and stop the engine on a better quality, ASTM No. 2-D type fuel to prevent plugging and sticking fuel system components and to permit satisfactory starting capability.
The same diesel power ratings may not always apply for Cat engines burning crude oil. Reasonable engine service life can be achieved when proper procedures are followed. However, the greater risks involved make it good practice to include slightly higher than normal maintenance costs when figuring the overall economics to be gained.
A fuel analysis should be performed. Include a distillation curve. Operation at light load is not recommended. On occasion, operation at 50% load has reportedly caused smoking.
Engines for crude oil fuel operation should be equipped with higher temperature thermostats, bypass centrifugal oil filter, and fuel injector pushrod keepers.