What does petrol do to a diesel engine?
- 07 December 2018
To keep people from accidentally filling a diesel engine with petroleum, a vehicle comes with a warning label “Diesel Fuel Only.” Despite this, misfuelling a vehicle occurs more often than one would think! The RAA reported 7,500 misfuelling events of people putting petrol into a diesel car per year, costing Australians up to $10 million annually.
The best-case scenario when this happens: You realise before driving and can call a tow company to drop your vehicle off at your local mechanic.
The worst-case scenario: You drive away with a diesel tank full of petrol. It’s likely you won’t get far before the engine starts to go “funny.”
The damage will depend on how much diesel fuel remained in the tank before the petrol was added and how new your diesel engine technology is. Fixing this problem could be as simple as draining the incorrect fuel or as costly as a full fuel system repair or replacement.
“What’s the damage?”
Combining petrol and diesel creates a solvent which plays havoc on your car’s fuel system. In any clean diesel engine vehicle manufactured after 2007, any amount of petrol present in the fuel tank will likely damage the sensitive emission control components and system.
In older engines with dated emissions systems a small percentage of petroleum (say 90% diesel/ 10% petrol) can pass through the system with no trouble. At its worst, it may reduce the engine power and make a bit of noise.
A large percentage of petrol in diesel engines, whether new or old, will result in catastrophic damage for your fuel system or the entire engine.
How catastrophic are we talking about? Well, first consider that each type of fuel is chemically engineered to detonate under completely different conditions. Using a high flash point diesel fuel incorrectly will make it combust at times that the engine isn’t expecting, which could send massive shockwaves through the pistons, wrist pins or connecting rods which are all vital components of the fuel system.
Explosive forces will, in turn, jostle or even dislodge other parts of the engine and send off a chain reaction that can destroy the complex mechanical system that the car relies on. This includes the fuel filter, fuel pump and fuel injectors which, as anyone who has had to replace them will attest to, is a costly exercise.
Fool-proofing the future
There have been many modifications made to modern diesel vehicles to help prevent this disaster happening in the future. In the early ‘80s diesel fuel filler openings were narrowed, but this didn’t prevent diesel fuel being accidentally put into petrol vehicles. About ten years ago BMW started including “misfuelling protection devices” into its range, and Audi and Volkswagon quickly followed suit. Now every diesel car manufactured is configured to only accept diesel fuel.
At Bulk Fuel Australia we know how important it is to have the right type of fuel ready for every occasion and type of vehicle. Our range of on-site fuel delivery vehicles have the equipment to keep every type of engine, machine or vehicle running smoothly across Australia. Contact Bulk Fuel Australia today to talk about our fuel delivery network.