Is it possible to flush the engine with diesel fuel?
Content
Positive effect and possible negative consequences
Diesel fuel has excellent dispersing ability. That is, it dissolves even old deposits of various nature, including sludge. Therefore, many motorists 20-30 years ago actively used diesel fuel as an engine flush fluid. That is, in those days when engine parts were massive with an impressive margin of safety and minimal requirements for fuel and lubricants.
In addition, some diesel fuel, which will certainly remain in the crankcase, will not have a pronounced negative effect on the new oil. It is not necessary, after washing the engine with diesel fuel, to somehow expel the remaining diesel fuel from the crankcase or fill in and drain fresh oil several times.
Also, this method of cleaning the motor is relatively inexpensive. When compared with flushing agents, and even more so with specialized oils, washing the engine with diesel fuel will come out several times cheaper.
This is where the positive aspects of this procedure end. Let's briefly consider the possible negative consequences.
- Lumpy exfoliation of solid deposits. Sludge build-up accumulates on static surfaces in many motors. Diesel fuel can simply separate them from the surface and dump them into the pan. Or run into the oil channel. Which will cause partial or complete blockage and oil starvation of any friction pair.
- Negative effect on rubber (rubber) and plastic parts. The vast majority of modern seals and retainers in the engine made of plastic and rubber are resistant to the chemical attack of any petroleum products. But "tired" non-metallic parts of diesel fuel can destroy to the end.
- Possible damage to the liners and the formation of scoring in the friction pairs of the ring-cylinders. Diesel fuel does not have sufficient viscosity to create any kind of strong protective layer.
All these consequences are probable. And they do not necessarily come in every single case.
In what cases is it absolutely not worth washing the engine with diesel fuel?
There are two cases in which flushing the engine with diesel fuel before changing the oil will more likely have a negative effect than a positive one.
- Very tired motor with high output. It is not without reason that some car operating instructions say that after a certain amount of time (when the engine wears out and all the gaps in it increase), it is advisable to start pouring thicker oil. This is done to compensate for gaps due to the thicker and more durable oil film that thick oil creates. Solar oil has a very low viscosity. And even with its short-term use, metal-to-metal contact in all loaded friction pairs will be irreversible. The result is accelerated wear to the limit state and a high likelihood of jamming.
- Modern technological engines. It is out of the question even to use a regular oil with the wrong viscosity. And the use of diesel fuel as a flush at least (even with a single fill) will significantly reduce the life of the motor.
It is theoretically possible to use diesel fuel as a flushing fluid on engines that are primitive by modern standards (old non-turbo diesel engines, VAZ classics, outdated foreign cars).
Feedback from motorists who have tried the diesel fuel flushing method
Good reviews about the method of washing the engine with diesel fuel are mainly left by owners of outdated equipment. For example, drivers often wash ZMZ and VAZ engines with diesel fuel. Here, in most cases, there are no pronounced negative consequences. Although it is not a fact that in one wash the car owner did not cut the engine resource of thousands so much by 50 km.
On the Internet, you can also find negative reviews. For example, after pouring diesel fuel, the engine jammed. After disassembly, worn out and cranked liners were found.
Therefore, the conclusion about this method of cleaning the engine is as follows: you can use diesel fuel, but carefully and only on well-preserved obsolete engines.
