Diesel Problem

DannyW

DannyW

DannyW

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Ive just baught a fiesta 1.8 diesel, but my dad put 15 quid of petrol init.. run like poo, so we went back and put 15quid of diesel init so its like 60% diesel, 40% petrol

will this cause any long term damage?
 
DannyW said:
Ive just baught a fiesta 1.8 diesel, but my dad put 15 quid of petrol init.. run like poo, so we went back and put 15quid of diesel init so its like 60% diesel, 40% petrol

will this cause any long term damage?
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Yes, get the tank drained NOW
 
what year/engine type is it?

when the petrol was added, how much was already in there?

if its an old model, id be tempted to just brim it with diesel again and then learn fast
 
It's an old Fiesta Diesel.

It will be fine.

It's the newer high pressure turbo diesels which petrol can cause major problems.
 
I thought a mixture like that would not be a problem isn't it just gonna m,ake the derv a bit thinner or once u get to half a tank fill it up again.
 
Pre common rail diesels will just run a bit rough until the petrol is out of the system, just keep brimming it to dilute it and all should be ok.

If you put petrol in a common rail diesel then do not start it, it can do a lot of damage to the fuel system, especially the injectors. If you are lucky you can get away with flushing the whole system and cleaning it out, if you are unlucky you could end up having to replace most of the fuel system.

Fog
 
i know a few taxi drivers that swear by it for cleaning out there diesel engines.
they put a gallon or so in every so often, i think they had fords at the time.
i`d fill the rest of the tank up with diesel n drive it.
 
Aye, saw some program ( think it was that dodgy car program on Sky 1 ) and they did a test with a few oldish cars.

Had an old Diesel Astra ( N-P reg ish ) and topped it up with petrol and it ran fine for a long time :/ got a bit rough after god knows how many miles and then they put diesel in it again and it was fine :/ well as fine as it could be :P

Wouldnt make a habit of it but it should be ok :) like they said, keep filling it with diesel to keep thinning the mix of petrol
 
Smiley Man said:
could someone actually give a technical explanation of why petrol wont work in a diesel engine and vice versa?

thanks :)
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I am no expert but here goes.

In a petrol engine you have spark plug to ignite the petrol. However diesel is not flammable but combustiable, thus the spark plug will do nothing and will just become oily.

In a diesel engine the diesel fuel is injected and then compressed to a high pressure which then ignites the diesel. [This im not sure about] obviously the petrol still ignites as I have seen old diesel run on petrol, not as good as runnning on diesel though. The only thing that will happen on an old diesel is that the injectors will not become lubricated by the oily diesel and thus will start to degrade over time.


I think that is the jist of things, I'm sure someone will amend or add to what I have written.
 
It combusts at different pressures and temperatures :/


Diesel engines dont have sparkplugs etc, the fuel/air mix just explodes because diesel becomes quite volatile when its atomised and injected into a hot and pressurized environment :P


The precise time when the fuel is injected is all preset to work with diesel so if you put a different fuel in there with different properties ( ie: ignites at different pressures and temps ) then it wont run very smoothly :P to say the least


**edit**

Diesel also has lubricant qualities, so diesel fuel pumps are just lubricated by the fuel that passes through them ( not all of them but many of them ) so if you start passing a thinner fuel through there which has little or no lubricant qualities then the fuel pump will die sooner or later :P

Older pumps with lower pressures are obviously a little hardier :) but the modern day ones wont like it at all i suspect
 
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The main issue is the wear to the pump as petrol provides little in the way of lubricaton.

However, Fords 1.8 8-valve diesel engine is just about as agricultural as you can get in terms of road going engines, it's unlikely to do much damage. Is the tank full with the extra £15 worth of diesel in? If not brim it with diesel and get your old man to pay for it...
 
Just out of interest, has your engine got the Bosch fuel system of the CAV system? Not that I think it makes much of the difference to your opening question.
 
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