AAARRHHH! I put unleaded in my diesel - please help an idiot out

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A friend has just done the same with his Peugeot 106 Diesel, he didnt realise and kept driving till it stopped. Got it towed to mine and we drained the tank, changed the filters and an oil change, it runs but something is not right. It is missing at certain revs and smokes much more than it ever did, not sure what is wrong but must have been the petrol that has done it.
 
AA reckon that around 120,000 people do this each year in the UK and the number is growing.

If you have not tanked it heavily with petrol really all you need to do is drain the tank ASAP & change filters. I have heard it said that you can run with up to a 80/20 mix with a bit of extra oil added, but that was in the context of older engines and really to prevent winter fuel waxing. Not sure if a modern turbo diesel takes kindly to running on a much more volatile fuel mix.

If you do have to run it, keep the revs low and do not stress the engine. Good luck.
 
Well heres what I did.
found the receipt and it was only 11 litres, only :rolleyes:, which works out at 13% on the 83 litre tank.
A friend came over with 40 litres of diesel with 1 litre of 2 stroke aviation oil mixed in it, he swore that it would be fine. So fingers crossed we poured it in and started it. So far done around 10 miles and everything seems completely normal, got to a filling station and put andother 6 litres of diesel in, checked the pump 3 times first ;)

Question is do I take it over to my father in laws garage and empty the tank still? they both think it is not necessary, and said it would have packed up within a mile if there was going to be a problem.
 
no, i would carry on, just fill up again when it gets to 3/4 to dilute as much as poss. and keep doing that for a while.
 
gIzzE said:
Well heres what I did.
found the receipt and it was only 11 litres, only :rolleyes:, which works out at 13% on the 83 litre tank.
A friend came over with 40 litres of diesel with 1 litre of 2 stroke aviation oil mixed in it, he swore that it would be fine. So fingers crossed we poured it in and started it. So far done around 10 miles and everything seems completely normal, got to a filling station and put andother 6 litres of diesel in, checked the pump 3 times first ;)

Question is do I take it over to my father in laws garage and empty the tank still? they both think it is not necessary, and said it would have packed up within a mile if there was going to be a problem.


I honestly do not think you are going to get the definitive answer you want because who can tell. The biggest problem is the high pressure side of the fuel injection system which includes the high pressure pumps - they are probably least tolerant and the wear issues may be a killer or maybe not.....very difficult to predict.

The engine itself is less likely to be affected now that you have 'diluted' it down but would advise you take it very easy while you have the mix in the system.

Good luck

NormanB
 
Thanks for all the advice guys.
 
I'm not sure if this has been mentioned yet (about to leave work and haven't had time to read through) but BP have paid for a number of customers to have the tank drained as they acknowledge the confusion over the similarly coloured pumps. I read this somewhere.
 
WARNING!!!!!!!!!!!!!!!!!!

The new high pressure pumps fitted to MB CDi engines are not tollerant to petrol.
There have been many cases of knackered pumps even when the petrol has been diluted. This knackers the whole fuel system due to steel filings.

DRAIN THE TANK!!!!!!

The old adage of diluting the petrol and adding lubricating oil is not sufficient for the close tollerance, high pressure pumps now.

Also add some engine oil or two stroke to your first full tank of diesel as extra lubrication.


I've seen a new Ford Mondeo TDCi knackered on it's first day on the road. Only did something like 10 miles. :eek: :eek:
 
jimmy said:
A friend has just done the same with his Peugeot 106 Diesel, he didnt realise and kept driving till it stopped. Got it towed to mine and we drained the tank, changed the filters and an oil change, it runs but something is not right. It is missing at certain revs and smokes much more than it ever did, not sure what is wrong but must have been the petrol that has done it.


This is going to range from siezed pump if you're lucky to blown head gasket, holed piston or melted pre-chamber. Doesn't sound too good.

Lucky you've had your engine repair practice recently Jimmy.

Compression test will reveal all.
 
Interesting that the car it's fitted to is a Subaru.. They ain't no diesel Scoobys.
 
Ouch... Easy mistake, a headache to sort out !

The AA report highlights the dangers and potential expense of running the enginer with the wrong fuel with frightening impact.

Diesel has a greater specific gravity (0.84) than Unleaded fuel (0.75) suggesting it would sink to the bottom of the tank and, perhaps get drawn into the engine first.

The oil fractions would not be readily miscible but additives may transfer between the layers. There is a danger the unleaded fuel would remain as a layer in the tank despite constant refuelling.

I appreciate your hesitation to report the incident to MB but you should consider having the tank drained promptly...

Good luck, and err yes...
I've mistakenly put 4* in a Diesel Tranist van on hire, embarrasing but less than two hundred pounds to drain and dispose, rectify and refuel.
 
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tee hee dieselman - looks like a Legacy to me :)

and personally I'd go for a complete drain of the tank/system along with new filters

Andy
 
andy_k said:
tee hee dieselman - looks like a Legacy to me :)
yeah, no self-respecting impreza would have that much arch clearance or tyre sidewall! ;)
 
no more wrong fuel type - new fuel alarm unit??

Not quite sure if this will help but it may, see the product at Diesel Guard but its £1 cheaper on ebay, a new post see ebay link for diesel guard

The american voice is a bit naff but it could save £££££'s

Ian
 
tee hee grassmere - rewind by 5 posts on this very thread

DOH ! :eek: and I thought I read the posts so very carefully :)

Still the ebay ad will save a £1 :bannana:
 
I filled (as in a full tank) my diesel Hiace van with unlead at 1 in the morning on a wet Saturday in Sheffield, anyay I called the AA, they towed me away and drained the tank, cost me around £200 all in to buy new fuel on top.

I wont do that again, I'm paranoid when filling my tanks now.

Craig
 
use a thin pipe and an electric putm if you can get hold of one if not then a siphen hand pump will do, remove all the petrol undo the feed to the pump and turn the engine so all is out, change the filter then fill with dsl "you will need to purge the system" once started take it for a good burn up, simple job hardes part is getting it started
 
teky said:
use a thin pipe and an electric putm if you can get hold of one if not then a siphen hand pump will do, remove all the petrol undo the feed to the pump and turn the engine so all is out, change the filter then fill with dsl "you will need to purge the system" once started take it for a good burn up, simple job hardes part is getting it started

I have to urge caution here!

No disrepect intended here but - while I would quite happily use an electric powered pump with diesel, I would never use one where there is a possibility of petrol vapour. If I really wanted to be a buddhist monk I would do the long course, rather than the short hot one!
 

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