Petrol in Diesel

Flyer4u0

Well-Known Member
Hi
in a moment of stupidity I managed to put a quarter of a tank of petrol in my diesel car. I would say the ratio is 1/4 petrol and 3/4 diesel.
Any mechanics around that could give some advice.
thanks
Norm
 
It's better than the other way around, but still not good! It's a common trick in winter for truck drivers to put a little petrol in their tanks to stop the diesel from waxing up and aids starting. However, I would suggest that 25% is too excessive and will damage your car engine. Best get it drained for the sake of a tank of fuel over the cost of a new engine!
MS
 
A little petrol is OK and I have had a couple of gallons in a tank with no ill effects, but 25% is a bit much, probably best to have it drained,is it still running OK or popping and banging? if its running OK adding around 250/300 mil of 2 stroke oil might help, not great for the cat though.
 
If it's and older Diesel engine fill up the tank and run it when you have used a quarter of the tank fill it up again and then repeat this a good 4 - 5 times and you will dilute the contaminated fuel enough for it to not be a problem, if it's a new car under warranty what ever you do don't take it to the main dealer use a good independent garage it will cost you a fortune at the main dealer because they will replace everything from the tank through to the injectors and everything in line that has fuel in it.
 
Flyer, our Volvo XC60 Diesel was topped up with 30% petrol. Son in Law Mechanic said run it and top up. Ran 90 miles that eve and topped up. A bit lumpy starting the following morning, but ran 120 miles and topped up again. From then on- no problem.
 
nice white smoke cloud to escape in !! drain it off some wont hurt it as said otherway is the real cash burner. use it for burning later in the year . done it in my new works truck some years ago i just used the thing till i got to 1/4 then just filled up again.and as a bonus you will have a nice set of clean ejectors and pump
 
Thanks for the replies. I decided to get it drained £200 pound versus a £14000 car. Could have bought a nice toy with that money though. OUCH....
 
Filled wife's S-Max tank for the run home from Devon 4 summers ago

£80 spent... Realised I'd done it with petrol... £140 to get it drained... £80 to refill it with diesel... £300 is my most expensive tank of fuel ever

Have I heard the end of it yet? Have I b*ll*cks!
 
Petrol in a diesel is a very bad move. Even the smallest amount will reduce the lubricating performance of the diesel and with the very small clearances in your fuel pump and injectors can lead to metal to metal rubbing and an expensive failure.
Do not attempt to move the vehicle with the engine. Drain fuel, wash tank out and refill with diesel.
Do not chance the easy way, i.e. run it to lower the tank level, top it up and so on unless you can afford several hundred pounds if it goes wrong or you can afford to scrap the vehicle. Some may have got away with it but not many. Remember Murphy's or Sod's Law.
 
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Did a similar thing in a Navara a few years back. I decided to run it and keep putting diesel in. It worked ok. Wouldn't recommend it but as far as I know it didn't do any lasting damage. Lucky probably.
 
Petrol in diesel is fine!
It is often used as a winteriser in colder climates.
Yes it does thin the fuel, but it wont do any damage in smaller amounts.
I often ran around 10 - 15% misfuel in a HDI engine.
Arguably the HDI's have the greatest strain on their fuel injection system due to the injection pressures and it didn't do any harm.
 
I did this last year and decided to have the tank drained, the guy who did it said up to 5% petrol no problem, just fill with diesel, drive and fill again etc., and it would be OK. I'd got a 50:50 mix by the time I noticed so no option
 
I own a garage just down the road from a very busy petrol station... at least once a week someone fills up with the wrong fuel and the car ends up on my ramp having the tank drained, it's a nice lttle money spinner. I run my space heater on it or depending on the ratio I sometimes put it in my hilux which runs on just about anything.
 
If it's and older Diesel engine fill up the tank and run it when you have used a quarter of the tank fill it up again and then repeat this a good 4 - 5 times and you will dilute the contaminated fuel enough for it to not be a problem, if it's a new car under warranty what ever you do don't take it to the main dealer use a good independent garage it will cost you a fortune at the main dealer because they will replace everything from the tank through to the injectors and everything in line that has fuel in it.


The reason why main dealers change the whole fuel system is to keep your warranty valid!! If they don't and a few months later the inj. Pump goes the owner will want it done under warranty. Uh. No.
Thats why everything is changed. Claim under your insurance and keep the vehicle in warranty.
As I work in a land rover main dealer we see it quite a lot. Under Land rover warranty there are 3 levels of repair. From a tank out and clean, new filter to a whole new fuel system.

Most modern diesels have have a miss fuel flap in the filler so when you put a smaller nozzle in it trips the flap across the filler making it nearly impossible to fill apart from very slowly.


Anyway. Miss fuels keep my series 3 foxing wagon on the road ;)
 
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get it drained its a diesel engine not meant to run on petrol no lubricating properties in petrol.the fuel pump needs constant lubrication,petrol burns a lot hotter causing damage to the injectors dont let anyone tell you any different atb
 
I know plenty of people than run misfuel or mix petrol with diesel.
I did myself for many years for many reasons.

Now I would never go putting diesel in a petrol!

Diesel has more calorific energy.
Petrol has a higher auto ignition but diesel will expand more energy in its combustion.

get it drained its a diesel engine not meant to run on petrol no lubricating properties in petrol.the fuel pump needs constant lubrication,petrol burns a lot hotter causing damage to the injectors dont let anyone tell you any different atb
 
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