What causes diesel pre-ignition?
Abstract: In diesel engines, fuel is injected into the engine cylinder near the end of the compression stroke. As the piston continues to move closer to top dead center, the mixture temperature reaches the fuel’s ignition temperature, causing ignition of some premixed quantity of fuel and air.
What causes engine pre detonation?
Pre-ignition is caused by something in the cylinder igniting the air/fuel mixture. Common culprits are: Glowing hot or melted spark plugs. Glowing hot exhaust valve.
Can a diesel engine detonation?
Diesel combustion does not form a flame front; ignition occurs wherever fuel droplets and hot air come together. Because there is no flame front, there can be no prolonged heating of premixed volumes of fuel-air mixture, so there can be no detonation.
How do I get rid of pre detonation?
There are several ways to cure pre-ignition:
- Run higher octane fuel. Premium gas rated at 92 or 94 octane is best for an engine with a compression ratio between 9.25 and 10.25:1.
- Run the engine on the rich side.
- Try playing with ignition timing.
How is the fuel ignited in a diesel engine?
Injected fuel is ignited by its reaction to compressed hot air in the cylinder, a more efficient process than that of the spark-ignition internal-combustion engine. The diesel engine gains its energy by burning fuel injected or sprayed into the compressed, hot air charge within the cylinder.
How much pressure does it take to ignite diesel?
Diesel engines have no spark plugs to ignite the fuel. In the cylinder, the pressure is so great the temperature is very high. The pressure is so great (16:1 or 234 psi) that the temperature becomes high enough to ignite the fuel without a spark plug.
Can old fuel cause detonation?
The remaining fuel can detonate. A rich Air/Fuel Mixture runs cooler than a lean mixture. A lean mixture can get too hot and detonate.
How do you fix engine detonation?
Detonation Elimination: 9 Ways to Prevent Engine Detonation
- #1. Up Your Octane.
- #2. Keep Compression Reasonable.
- #3. Check Your Timing.
- #4. Manage Your Boost.
- #5. Monitor the Mixture.
- #6. Blow out the Carbon.
- #7. Examine Your Knock Sensor.
- #8. Read Your Spark Plugs.
How can fuel detonation be prevented?
What temperature does diesel burn at?
| Material | Autoignition Temperature oF | Source |
|---|---|---|
| Diesel | 950-1000 | [10] |
| Diesel | 1010-1125 | [4] |
| B100 (Biodiesel) | 705-840 | [15] |
| B20 (Biodiesel) | 980-1300 |