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Can a diesel run on 2stroke fuel/be supplemented with 2 stroke fuel mix? Answered

Hi all
can a diesel run on 2stroke fuel mix if the 2stroke oil was added to the petrol in heavy enough quantities so that 1. It off set the octane rating of the petrol so that it acted like diesel? 2. It was blended with diesel to supplement the mix? 
The reason I ask is that there is a lot of mistakes made at the fuel pump with people putting fuel in diesel and I was wondering if the petrol was know, that a measured amount of 2stroke oil was added that this would solve the problem, rather than the expensive issue of towing, draining and repairs? I have had this experience and drained most of the petrol and then added motor oil to the new diesel to help lubricate and no dramas. Positive comments please.



Best Answer 4 years ago

If you want positive comments only then i guess the only answer you want to hear is that it's doable. Unfortunately that isn't the case. It has nothing o do with octane rating. It has everything to do with combustion when under pressure. A 2 stroke mix or added oil isn't going to alter regular gas to a point where it's more combustible under pressure. If there was a better solution to poring the wrong fuel in your tank people would already be capitalizing on it.


4 years ago

I want to modify my other answer. First its gel and not jell, stupid spell checkers just suck me right in.

I found a much more in-depth answer about mixing gas and diesel. What i said is correct in that it does help prevent gelling. It also makes the fuel mix burn hotter which would explain the engine running better when its 40 below zero. Its actually keeping it warm. However the mix of fuels does cause a lot of problems, especially with injectors so once again, its something that you don't want to do except in an emergency. The text is as follows:

light distillates that gasolines are made from have a natural high-octane index.
The middle distillates that diesel fuels come from have a high cetane index. The
octane and cetane indexes are INVERSE scales. A fuel that has a high octane
number has a low cetane number, and a high cetane fuel has a low octane number.
Anything with a high octane rating will retard diesel fuel�s ability to
ignite. That�s why each fuel has developed along with different types of
engine designs and fuel delivery systems. Gasoline mixed in diesel fuel will
inhibit combustion in a diesel engine and diesel fuel mixed in gasoline will
ignite too soon in a gasoline engine.

will raise the combustion temperature. This might or might not reduce carbon
deposits in the cylinder. This also might or might not overheat the injector
nozzle enough to cause coking on the nozzle. That�s a clogged injector tip in
layman�s terms. The fuel being injected is the only thing that cools the
nozzle. Diesel fuel has a lower combustion temperature than gasoline. The fuel
injectors depend on the fuel burning at the correct rate and temperature for a
long life. If the combustion temperature is raised long enough, the gums and
varnishes in gasoline will start to cook right in the fuel injector and turn
into carbon. These microscopic carbon particles will abrade the nozzle. High
combustion temperatures alone will shorten fuel injector life, gasoline makes
the problem worse.

and alcohols do have an anti-gel effect on diesel fuel, but these fuels are too
thin and will hurt the lubricity. Alcohols work as a water dispersant in small
amounts, but also attract water in large amounts. Diesel fuel is already
hydrophilic (attracts water) so why add to the problem. The old timers got away
with this because high sulfur diesel fuel had enough lubricity to take some
thinning. Today�s low sulfur diesel fuels have adequate lubricity, but I
wouldn�t put anything in the tank that would thin out the fuel, reduce
lubricity, or attract water."

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Answer 4 years ago

​thanks cyber, I have since put in hi octane fuel as my car started running bad and then stopped due to, I believe, the diesel sitting in the bottom of the tank and now being the majority fuel source. The hi octane fuel got me going but only at idle speed, no acceleration. I got home. It's like it floods when I try to accelerate from un burnt diesel. According to your post above, hi octane fuel makes it worse. I will drain and leve for lawn mower, which works well. That bring me to another possible use. An old engine,carby with not cat converter and 10percent diesel? Yeah I know, give it up. What I really want is, what can I use diesel/ petrol mix for?


4 years ago

I can't imagine why you might want to do this but - the petrol will ignite before the oil giving you timing issues.

I am guessing your UK based and here Petrol is cheaper than diesel If things are that bad then most diesels will run on more or less any clean oil you can get, heating oil, chip oil, bio oil etc.

When veg oil was cheaper than diesel many people did just that.

All illegal though.


Answer 4 years ago

Its not illegal Rick, you are allowed to burn up to 2000 litres of veg a year, and not pay duty.


4 years ago

We actually have different grades of Diesel and different mixes of those grades. That is in part because of the extreme climate/cold. Regular diesel will turn to jell when it gets below 0 F so to keep the engines running you use #1 diesel which has a lower jell point. Running a mix of one and two gives a blend that is more jell resistant. Why not just run straight #1? Because its more expensive, although in Jan and Feb sometimes people do run straight #1. So what is the point of all of this? Well, on occasion when a big temperature drop happens and your blend is not right, you can add gas in small amounts to prevent jelling. About one gallon in ten does the trick. It also makes the engine run smoother in the extreme cold. So you can add some gas to diesel with no ill effects but its not something you want to do on a regular basis. Diesels tend to be pretty tolerant of fuels but using what is recommended is always best as that is what the engine was designed for.

Now gas engines are a different story. Adding diesel to gas is a bad thing to do and could gum up the spark plugs to the point that it will not run..


4 years ago

I have 3 diesel cars, running on biodiesel, all though I wouldn't add petrol to the fuel, as I do my own repairs, lots of people are doing it

have a look at