wiltshire landyman
I’m back
probably
nope - just keep topping it up with doozil every day.
2 Litre doozil? 
pos
Well-Known Member
No, it'll be absolutely fine. Petrol at that kind of ratio will just act like a good strength diesel injector cleaner. I would however advise that you add 1-2 litres of engine oil (mineral or semi-synthetic) just to help thicken the consistency of your fuel up a little. You might even notice it does some good if it hasn't had any diesel treatment run through it recently.
-Tom
-Tom
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discomania
Well-Known Member
It will be fine, stick a litre of engine oil in.
I know of someone who brimmed a Disco with Petrol, he bought 5 litres of oil and stuck in what he could, it was on a 450mile trip home, so he just stopped at every service station and added oil, then started adding diesel.
The problem is primarily lubrication.
I know of someone who brimmed a Disco with Petrol, he bought 5 litres of oil and stuck in what he could, it was on a 450mile trip home, so he just stopped at every service station and added oil, then started adding diesel.
The problem is primarily lubrication.
sinclair182
Active Member
I thought the petrol ignited earlier than diesel so it doesnt bang it the correct place for the pistons??? (Just what i was told im a noob be nice)
discomania
Well-Known Member
You are correct it will ignite sooner and can cause knocking, but your not going to be doing this for ever so it will be fine. The more diesel you add, and the more oil, your cetane rating (measurment of your fuels ignition factor) will be brought back to normal and it will be OK.
sinclair182
Active Member
Aaaahhh. And now I know!
RedditchJay
New Member
SHOULD ??? we add some petrol over the winter , say 1 gallon petrol per 8 gallons derv to thin the derv for low temps or is modern day derv better than it used to be {thread hijack..sorry}
discomania
Well-Known Member
Diesel sold in winter months is winterised, and ought to be OK, however I remember looking at the specification last year and it looks like it was only good to about -15°C, so if we get another winter like the last two winters we got it could potentially get cold enough to sludge it up. I have a friend who lives out in the sticks, he couldn't get his RR going because the diesel was like sludge - and that was pure diesel no SVO or anything.
Kero is actually a better additive but HMRC might get upset, although, how often will they be out and about dipping tanks at -15°! Petrol is obviously allowed in your fuel tank so is probably a safer option.
It was once fairly standard practise to put a gallon or two of petrol into each tank of diesel in trucks but they tend to use additives now. All the engines pre TD5 would be happy enough with a gallon of petrol in on top of a tank of diesel to help winterise it.
The TD5 being common rail can suffer gassing of the petrol when the head is up to temp – fuel in the TD5 returns at over 60°C!
Kero is actually a better additive but HMRC might get upset, although, how often will they be out and about dipping tanks at -15°! Petrol is obviously allowed in your fuel tank so is probably a safer option.
It was once fairly standard practise to put a gallon or two of petrol into each tank of diesel in trucks but they tend to use additives now. All the engines pre TD5 would be happy enough with a gallon of petrol in on top of a tank of diesel to help winterise it.
The TD5 being common rail can suffer gassing of the petrol when the head is up to temp – fuel in the TD5 returns at over 60°C!
Grimmer
THE Winner
I put a couple of litres of petrol 3-4 per full tank of doozil in my tank last winter when it was really cold and it certainly seemed to start easier in the mornings.
Oldseadog
Well-Known Member
Only if you put diesel in a petrol engine, as the spark ignites the petrol which in turn ignites the diesel.
However in a diesel, the petrol would be ignited by the diesel, and so you would effectively have a slightly retarded 'second bang'.
It certainly shouldn't do any harm to your engine, and would give your fuel system a good clean out!
OSD
Shifty1962
Well-Known Member
Not correct. In a diesel engine the fuel is ignited on injection by the heat generated compressing the air in the cylinder - no spark necessary. It takes a lot of heat to get diesel to ignite but petrol will burn more vigorously and ignite very easily at much reduced temperatures. Try lighting ann egg cup of diesel with a match.
The problem with injecting petrol into a diesel engine is that it contains much more energy than diesel for the same volume of fuel and it burns hotter and faster providing very little lubrication subjecting the engine to stresses it was not designed to take. Pressures in the cylinders can far exceed those generated by burning diesel and head gaskets, piston rings, and con rods are often the weak point. That is why petrol engines run at much lower compressions to prevent pre ignition by compression alone.
A 10% petrol mix in the colder weather will do no harm but accidentally starting a diesel engine on neat petrol can cause all sorts of damage. It will run but very quickly the valve faces and piston crowns will overheat. If you continue to run the engine, assuming your diesel injection pump does not seize and the head gasket does not let go, then the pistons will seize in the bores.
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discomania
Well-Known Member
Other way around... Petrol has an octane rating, this is how much it can be compressed before it will ignite, Diesel has a cetante rating, this is how easily it will auto ignite.
If you were to apply the cetane rating to petrol you would discover it is much higher than that of diesel, in other words, the petrol will ignite sooner, and ignite the diesel with it, but as the engine is a diesel it has been set up and timed to give the diesel long enough in the cylinder at the compression stage to get up to temp and auto ignite. Throw in lots of petrol and it will ignite too early cause knocking and reduce engine efficiency as an internal battle roars.
stchris356
New Member
This all depends which engine you have in your Defender.
If it's the Ford TDCI unit you need to be careful as unlike the TD5 it's a common rail unit and under no circumstances should have any fuel other than diesel as the high pressure pump reqiures the diesel to lubricate it.
If this does not happen swarf will break off the pump and sent around the system.
The TD5 however is not common rail, although I wouldn't advise against cross contamination just keep topping up with diesel and you should be fine.
The 300Tdi which uses the old style rotary pump, again not recomended but you should be fine topping up with diesel.
If it's the Ford TDCI unit you need to be careful as unlike the TD5 it's a common rail unit and under no circumstances should have any fuel other than diesel as the high pressure pump reqiures the diesel to lubricate it.
If this does not happen swarf will break off the pump and sent around the system.
The TD5 however is not common rail, although I wouldn't advise against cross contamination just keep topping up with diesel and you should be fine.
The 300Tdi which uses the old style rotary pump, again not recomended but you should be fine topping up with diesel.
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Shifty1962
Well-Known Member
I beg to differ. The TD5 is a common rail diesel engine. The common fuel rail is internal to the cylinder head rather than piped externally. Later EU3 spec TD5s use an external spill rail.
However the TD5 does not use an injection pump as the injectors themselves generate between 2200 and 3000 bar by use of cam driven plungers.
The equivalent of the lift pump on earlier Tdi engines is the fuel tank mounted pump that transfers fuel to the fuel pressure regulator at more than 60psi in a continous circuit through the cylinder head which is why hot fuel is returned to the fuel tank. Makes the TD5 perfect for bio fuel as you dont need heaters etc.
However the TD5 does not use an injection pump as the injectors themselves generate between 2200 and 3000 bar by use of cam driven plungers.
The equivalent of the lift pump on earlier Tdi engines is the fuel tank mounted pump that transfers fuel to the fuel pressure regulator at more than 60psi in a continous circuit through the cylinder head which is why hot fuel is returned to the fuel tank. Makes the TD5 perfect for bio fuel as you dont need heaters etc.
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