What would happen if you put gasoline in a diesel engine?
Diesel and gasoline engines operate differently and require different fuels to run properly. Gas stations use different sized nozzles to avoid confusion. However, smaller nozzles will still fit into a diesel car’s tank.
Using the wrong engine oil by mistake is not ideal, but using the wrong fuel can have disastrous consequences. But what exactly happens if you accidentally put gasoline in a diesel engine? And what should you (and shouldn’t) do when this happens?
Comparing gasoline and diesel
There are many important differences between gasoline and diesel fuel in terms of their composition and how they function. The most obvious difference between these two fuels is how they are ignited.
Gasoline burns when ignited by a properly timed spark from a spark plug. Diesel fuel, on the other hand, burns due to the heat generated by high compression. The overall volatility of gasoline and diesel fuel is also rated using various overall scales.
Gasoline’s total octane number generally ranges from 87 to 90+, with the lower end of this range serving as the “standard” grade. Diesel fuel’s cetane number, on the other hand, is typically between 40 and 55.
Diesel fuel burns slower on average than gasoline, but delivers a higher energy yield with each combustion cycle. These figures vary depending on the application, but diesel combustion is generally considered to be 20% more efficient than gasoline. This results in the much greater torque that diesel engines are known for.
Immediate and Short-Term Effects (of Gasoline in a Diesel Engine)
Filling a diesel vehicle’s fuel tank with gasoline usually results in a number of short-term effects as a direct result. The most notable of these effects are:
1) Failure to Start/Stop
In many cases, diesel vehicles will begin to run poorly almost immediately after filling the fuel tank with gasoline. This will commonly result in stalling and failure to start after the stall has occurred. By this point, fuel system damage and wear to the engine internals have often already occurred.
2) Pre-ignition/detonation
Adding gasoline to a diesel engine can also cause a condition known as pre-ignition or detonation. This is the result of combustion at the wrong time due to the high temperatures achieved by the increased compression values common in diesel engines. Pre-ignition is known to cause severe damage to the engine internals.
3) Fuel system damage
Diesel fuel has natural lubricating properties that gasoline does not have. This additional lubrication helps prevent damage to many components of the fuel system, such as: A. Preventing high pressure fuel pumps. Without this lubricant, these components can break down within minutes.
Long Term Effects (Gasoline in a Diesel Engine)
Adding gasoline to the fuel tank of a diesel vehicle can often have secondary effects as well. These effects can take years to appear, but are still worth keeping in mind.
1) Fuel Tank Delamination
Most diesel fuel tanks have a special coating on them to prevent deterioration. These coatings have been proven to degrade rapidly when in contact with gasoline. This can cause significant issues in the vehicle’s fuel system in the long term. In some cases, it may take 1-2 years for such issues to occur.
2) Residual Engine Damage
Another issue associated with adding gasoline to a diesel fuel system is the possibility of internal damage that may have occurred but is not immediately apparent.
Although excessive or accelerated wear/deterioration of the engine may not have been noted at the time of the accident, this does not mean that all damage was avoided. In some cases, this damage is minor at first and worsens over time.
What to do if you have accidentally put gasoline in your diesel engine?
If you have come to the disturbing conclusion that you have put gasoline in your diesel tank, there are a few things to keep in mind.
(1) Do not start the car – If you suspect that you have accidentally put gasoline in the fuel tank of your diesel vehicle, do not, under any circumstances, start the affected vehicle or turn the ignition “on”. This will immediately contaminate the fuel system.
(2) Empty the fuel tank – Next, empty the entire fuel tank of the affected vehicle. In some cases, it may be necessary to lower the fuel tank to make it easier to empty.
(3) Flush the tank with diesel – Even after emptying the tank of the affected vehicle, it is recommended to flush the tank itself with clean diesel fuel. This will ensure that no gasoline residue remains.
(4) Fill with diesel – Once all of the above steps have been completed, fill the vehicle’s fuel tank with fresh diesel and start it.
IMPORTANT
If the affected vehicle has already started and is running, pull over to the right as soon as possible and turn off the ignition. Do not restart the vehicle, instead have it towed to the nearest trusted service center for further inspection.
