Wrong Fuel - '13 V70 D5

[GMC]

Advice please.....

Stupid mistake today. Near empty tank - started filling with Petrol, almost 13ltrs.

When I realised, I put in 60ltrs of Diesel. My fuel warning light was on, with 40mls left, so assuming around 5 ltrs left so in tank now around 60-65ltrs diesel & 13lts petrol.

With it diluted, I didn't expect any issues. I've driven about 40mls and to be honest, the car is going ok, but after the 40ml journey, when starting the car turns over more to start, just a a couple of seconds. Still drives fine though

My plan was to keep diluting with Diesel.

Has anyone done this?

Keep diluting or drain the tank?

[Tannaton]

I would personally continue driving gently until the thank is approx 1/2 full then I'd fill with diesel again - I'd repeat that maybe 3 times and then drive as normal.

In my experience any diesel engine will run quite happily on an occasional mis-hap of 10-20% petrol/diesel mix (you are at circa 20%). In some cases they seem to run better afterwards - it cured my uncles X-Type Jag from smoking. The long starting cycle is the first symptom you see when you've got some petrol in there.

If you are worried still - if you are a DIY chap you could drain out 50% of the tank and refill with fresh diesel or call out a local "fuel doctor" service. Or maybe add 250ml of synthetic 2 stroke oil. Do not go to the dealer as they will likely relieve you of circa £7000 on an entire new fuel system from the in-taken pump to the injectors (which I think is the VIDA process).

I realise others might find my view controversial but it's based on running a number of cars in this way and friends/customers who have done so without any consequence whatsoever. But if the worst did happen (and I have yet to see any post on here in 7 years where someone did damage an engine by running on the wrong fuel) the only part it will really impact due to insufficient lubrication is the high pressure pump - these are so reliable in normal use there are hundreds for sale on ebay - circa £100-£150 for one for the later twin turbo engines.

If you ask any long serving petrol forecourt attendant - there are many drivers of old black cabs and land rovers who regularly run their cars on a 10-20% petrol/diesel mix say every 5th tankful. These are usually older engines with traditional mechanical injector pumps but actually common rail systems are less susceptible as less moving parts are lubricated by the fuel.

[GMC]

Thanks for that. An excellent, knowledgeable & well thought out response!

I'll keep you updated.

Thanks again

[XC90Mk1]

Personally with that amount (I understand that sun 5% is supposed to be maximum dilution) I would probably have called it a day and had it drained. That said, the issue you have is of course that the diesel is acting as a lubricant and the petrol is a solvent so will strip the lot off.

Now it’s run if it were me I would top it up with diesel once again and continue to do so.

It’s not as I understand it the ‘Petrol in diesel’ that’s the real problem, it’s the total amount of petrol in their.

What I would say is that you should probably get any journeys you want to do out the way and use up the fuel in order to prevent petrol damaging any of the diesel specific seals and lines etc.

I would not wait to half ful before brimming with diesel again.

Good luck and let us know how you get on.

[Clan]

Originally Posted by GMC

Advice please.....

Stupid mistake today. Near empty tank - started filling with Petrol, almost 13ltrs.

When I realised, I put in 60ltrs of Diesel. My fuel warning light was on, with 40mls left, so assuming around 5 ltrs left so in tank now around 60-65ltrs diesel & 13lts petrol.

With it diluted, I didn't expect any issues. I've driven about 40mls and to be honest, the car is going ok, but after the 40ml journey, when starting the car turns over more to start, just a a couple of seconds. Still drives fine though

My plan was to keep diluting with Diesel.

Has anyone done this?

Keep diluting or drain the tank?

Diesel lubricates the injectors and fuel pump which run at extremely high pressure , so high forces involved ,. dilute it with petrol could result in a £2000 + bill sooner or later .

[Kev0607]

Originally Posted by GMC

Advice please.....

Stupid mistake today. Near empty tank - started filling with Petrol, almost 13ltrs.

When I realised, I put in 60ltrs of Diesel. My fuel warning light was on, with 40mls left, so assuming around 5 ltrs left so in tank now around 60-65ltrs diesel & 13lts petrol.

With it diluted, I didn't expect any issues. I've driven about 40mls and to be honest, the car is going ok, but after the 40ml journey, when starting the car turns over more to start, just a a couple of seconds. Still drives fine though

My plan was to keep diluting with Diesel.

Has anyone done this?

Keep diluting or drain the tank?

My Brother did the same on his Vauxhall. First thing he did was changed the fuel filter. Then he just used a 1/4 of a tank & refilled with diesel & done that 3 times. He never had an issue, luckily. After he added diesel the last time, he changed the filter again.

In your instance, I’d do the same. I’d keep diluting your tank with diesel, but I wouldn’t wait until you’d used half a tank of fuel before doing it. I’d change the filter right away, keep adding diesel every time you used 1/4 of a tank maximum, repeat 3 times, replace the filter the last time & then proceed as normal.

[Zebster]

My wife recently put petrol in her diesel Kia. I advised her not to start it and instead arranged for it to be drained and flushed. I would never suggest running a common rail diesel engine if the fuel was contaminated with petrol as it will cause pump wear and shorten the life.

[monkeh]

Advise to drain the tank using the in tank pump, common rail diesels are fussy old units. Diesel is lubrication for the high pressure pump.
It's a bit of a culture shock swapping from a mechanical pump to a common rail for me, my d24tic used to run on 30/70 petrol, veg oil, waste motor oil, atf, a bit of kero, ran perfect.
If you don't want to drain the tank and are wanting to preserve lubricity, dump a full 1l bottle of synthetic low ash 2 stroke oil in. You should be alright, just keep the tank topped up with diesel.

[Tannaton]

A lively topic as I thought....

A few more points mainly petrol is Just another fraction of oil, it does not impede the lubricating properties of diesel it just dilutes it, hence low percentage mixes have little to no impact.

But how much petrol is too much? How about a 98% mix of petrol and 2% lubrication? That’s what nearly all agricultural and motorcycle two stroke engines run on and rely solely upon for lubrication of pistons, bores, big end and main bearings...

[Bonefishblues]

Originally Posted by Tannaton

A lively topic as I thought....

A few more points mainly petrol is Just another fraction of oil, it does not impede the lubricating properties of diesel it just dilutes it, hence low percentage mixes have little to no impact.

But how much petrol is too much? How about a 98% mix of petrol and 2% lubrication? That’s what nearly all agricultural and motorcycle two stroke engines run on and rely solely upon for lubrication of pistons, bores, big end and main bearings...

...but are specifically designed to do that, of course. CRDs are designed to run on the comparatively modest (AFAIK) lubricating effect of neat diesel.

I'd have sucked it up (see what I did there) and drained, but am cautious by nature.