Petrol in a Diesel Boat
Putting petrol into a diesel marine engine is one of the most damaging fuelling mistakes you can make on the water. Diesel relies on its own oily film to lubricate the high-pressure injection pump and injectors; petrol strips that film away and acts as a solvent. On a boat the risk is compounded — you are often a long way from a ramp, and the temptation to "just motor back" can turn a drain-and-flush into a full injection-system rebuild.
Call Now: 0800 769 00024/7 marine fuel recovery — nationwide
What to Look For
You fuelled from a petrol bowser or jerry can by mistake
Engine hunting, knocking, or refusing to hold idle after fuelling
White or grey smoke and a sharp petrol smell
Loss of power on the way out of the marina
A fuel receipt that shows 91/95/98 instead of diesel
Common Causes
Shared fuel dock
Petrol and diesel bowsers sit side by side at most marina fuel docks — an easy mix-up under time pressure.
Jerry can confusion
Topping up from an unlabelled or wrongly-labelled jerry can carried aboard for the auxiliary or tender.
New or borrowed boat
Owners moving from a petrol outboard to a diesel inboard often fuel out of habit.
What to Do — and What Not to Do
Do
- Stop fuelling the moment you realise
- Switch off and keep the engine off
- Secure the vessel safely at the berth or mooring
- Note how much petrol went in and call 0800 769 000
Don't
- Start, crank, or run the engine
- Attempt to burn off contaminated fuel by running it
- Top up the oil or fuel before the system is assessed
- Motor the vessel back to the ramp under its own power
- Pump contaminated fuel overboard — it is an environmental offence
How Recovery Works
Frequently Asked
Can I just run it out?
No. Running a diesel on petrol-contaminated fuel damages the injection pump and injectors almost immediately. Keep it off.
How do you get to my boat?
A certified marine technician attends your berth or mooring. Where the vessel must be moved, we coordinate haul-out or transport to a marine workshop.