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Petrol in diesel tank
DarrenW - 11/2/08 at 12:30 PM

A lad on Ne7ers has just posted to say his step dad has put 6 litres of petrol in their brand new diesel Volvo Car (model unknown) and is wondering if its OK to fill with diesel and run it through. Tank was almost empty when he put it in. Car has done 1 or 2 miles.

Any modern diesel experts here?


dan__wright - 11/2/08 at 12:32 PM

drain it


britishtrident - 11/2/08 at 12:34 PM

It will have to be drained any more than a couple of litres in a full tank could damage the pump.

Older diesels were a bit more tolerant.


twybrow - 11/2/08 at 12:38 PM

Petrol in a diesel = bad news (knackers the fuel pump pretty darned quick, as diesel is a lubricant). Drain, flush, and maybe new tank!


smart51 - 11/2/08 at 01:03 PM

Petrol ignites at lower pressures than diesel so the engine won't run on it. New engine time. I guy I used to work with did this on a company pool car. Needed a new engine. He was caught the next day draining the fuel tank of another pool car. He'd done the same thing.

Even if the engine will run on blended fuel (low compression diesel will), the rest of the system has to be able to cope.


whitestu - 11/2/08 at 01:06 PM

I've done it 2 times in my company Passat - probably about 5 litres. I couldn't tell the difference and I've seen no ill effects.
If I owned the car I'd probably drain it though.

stu


DarrenW - 11/2/08 at 01:10 PM

OK, thanks all. Ill let him know, sounds like if hes feeling brave its a drain job, if not its flush the system time.


I did here that if you mis-fuel you shouldnt even unlock the car with keyfob as on some cars the pumps prime up in readiness for firing the car up.


Mr Whippy - 11/2/08 at 01:35 PM

hmm might get some decent performance


Jon Ison - 11/2/08 at 01:37 PM

I put 25 litres into a 70 litre tank, filled the rest with diesel no ill effects.


andyps - 11/2/08 at 02:09 PM

I put about 10 litres in a Citroen Berlingo Diesel which would have been about a 50-50 mix. Realised it 50 miles later, filled up with Diesel and so far all is well - that was about 6 weeks ago. It is a relatively low spec diesel engine though - the old 1.9D.


britishtrident - 11/2/08 at 02:28 PM

Problems tend to appear 6 months down the line.


Jon Ison - 11/2/08 at 02:53 PM

I'm not saying it cant cause problems by my episode was 2 years back.


macspeedy - 11/2/08 at 03:31 PM

The petrol attacks the coatings on the pump. been there done that and got a warning for it... but they did pay the 800 squid bill


andyps - 11/2/08 at 09:24 PM

quote:
Originally posted by britishtrident
Problems tend to appear 6 months down the line.


Why would that be? I understand that most problems relate to lack of lubrication from petrol as opposed to diesel, therefore surely they are likely to show themselves fairly quickly whilst it is not being lubricated rather than later, or am I missing something here?


Schrodinger - 11/2/08 at 09:35 PM

Recently read an article about the AA recovery team that deals soley with this.
IIRC they drain the tank separate the two fuels and then top you up to get you to a garage, I can't remember the cost but could be worthwhile giving the AA a call.


jono_misfit - 11/2/08 at 09:42 PM

When my dad did this on his week old car (filled about 50ltrs of petrol) he hadnt realised and drove the 2 miles down the road (it had started spluttering at the end).

We got an old electric fuel pump and some spare hose and pumped out the tank. Filled it with diesel, bled the system and it ran fine.

Its now done a further 160,000 miles without a problem.

If you can, pump it out