Old Seadog
Member
- Posts
- 71
- Location
- Ruabon, near Wrexham
Having heard rumours about the quality of supermarket diesel I conducted some tests with my 1997 Discovery 300 Tdi by driving around 1000 miles on each of Shell V-Power , Shell and Esso bog-standard diesel and supermarket stuff from Sainsbury and Tesco. Results were as follows:-
V-Power cost 22.87p per mile (£22.87 per 100 miles)
Shell and Esso cost 22p per mile and
Supermarket cost 21.5p per mile.
If you have a 20p per litre discount voucher for Tesco, that brings the cost down to between 18 and 19p per mile.
Not much in it, really, but it is very noticeable, even in this 132000 mile engine, that she runs a lot smoother on "real" diesel than on supermarket stuff. Couldn't detect any difference with the V-Power but I suppose that's no surprise in a relatively low-tech engine.
I have also used recycled cooking oil which is very cheap at 50p per litre but performance is reduced, starting is not so good, it will wax up in cold weather and you need to keep a close eye on the filter of the lift pump and also the fuel filter if you don't want to come to a sudden stop when it blocks up with the clag cleaned out by the veggie oil. Mixing it with diesel helps but then it doesn't save enough to be worth the bother.
I also tried heating oil (Kerosene or Paraffin) with 5% vegetable oil added. This was proper rapeseed oil in a bottle from the supermarket, not the thick old recycled stuff. The rapeseed oil lubricates the pump and gets the specific gravity to more or less what the engine was designed for. The old girl ran fine and fuel costs were at least halved. That was, of course, done purely and strictly in the interest of science and I neither recommend the practice nor do it myself now the experiment is over.
V-Power cost 22.87p per mile (£22.87 per 100 miles)
Shell and Esso cost 22p per mile and
Supermarket cost 21.5p per mile.
If you have a 20p per litre discount voucher for Tesco, that brings the cost down to between 18 and 19p per mile.
Not much in it, really, but it is very noticeable, even in this 132000 mile engine, that she runs a lot smoother on "real" diesel than on supermarket stuff. Couldn't detect any difference with the V-Power but I suppose that's no surprise in a relatively low-tech engine.
I have also used recycled cooking oil which is very cheap at 50p per litre but performance is reduced, starting is not so good, it will wax up in cold weather and you need to keep a close eye on the filter of the lift pump and also the fuel filter if you don't want to come to a sudden stop when it blocks up with the clag cleaned out by the veggie oil. Mixing it with diesel helps but then it doesn't save enough to be worth the bother.
I also tried heating oil (Kerosene or Paraffin) with 5% vegetable oil added. This was proper rapeseed oil in a bottle from the supermarket, not the thick old recycled stuff. The rapeseed oil lubricates the pump and gets the specific gravity to more or less what the engine was designed for. The old girl ran fine and fuel costs were at least halved. That was, of course, done purely and strictly in the interest of science and I neither recommend the practice nor do it myself now the experiment is over.
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