Just in case anyone is bonkers enough to try it!
"Red diesel. One other word of warning. If anyone is thinking of buying "cheap" diesel, don't bother. It is more than likely rebated or red diesel that has had the dye stripped out. Forget all those fanciful tales of pouring it through fuller's earth to remove the dye, it's just not true. What they actually use is Oleum (fuming sulphuric acid) & cat litter (the active ingredient contained in it, that neutralises the smell of cat urine also does wonders at removing dye), lime or cement powder, then filter it again thru cotton wool or a one micron industrial steam filter. This not only strips the dye but also all of the lubricity agents and all the other additives that are added to DERV, anti-wax & anti-foam. The resultant toxic sludge is then dumped at the side of the road, with all the resulting environmental impacts. Oh... and because red diesel has a different SG to DERV, the hygrometer trick still works equally as well. Most HM C&E roadside testing (dipping) used to be done with a clear squeegee bottle and a pipe, they would simply take a sample from your tank, look at the colour, either nick you on the spot or put it back in the tank and let you go on your way. But now they have very neat, small portable mini labs to test your DERV at the roadside. Kerosene (28sec oil) is commercial/home heating oil which is known as 'kero' or 'paraffin'. It is straw/orange in colour, very clean burning (has a very low sulphur content) and economical to use, however it contains no lubricant and is thus not suitable as fuel for engines. Even when mixed 50/50 with DERV, HM C&E roadside checks can still detect it, using their new high-tech mini labs. "