ralton wrote:

You guys are crazy. I wouldn't add 2-stroke oil to my Puma if you paid me to. Likewise, why mess with the highly qualified Chemical Engineers and Chemists at the big oil producers? Also, there would be an official notice in the owners manual or from the LR dealer if it was a good thing? Food for thought?

Well, I guess depends on your budget!

I'm adding it to every other fill-up, and Forte twice a year.

Had read that the optimum ratio to add was 1:200, so for a full tank on a 110, you are looking at 375ml. I use an old plastic (see-through) drinks bottle, marked up with a line at 375ml.

Of course, if you're NOT putting in 75litres at fill-up, you need to do some swift mental arithmetic to work out the dilution, taking into account the amount already in there.

This is why I'm only adding to every other tank, as I don't trust my arithmetic!


Whilst we're on this subject, does anyone have a good source for suitable 2-stroke oil in bulk. I've been buying the Halfords 1l bottles, which isn't very cost-efficient!

blackwolf wrote:

This two-stroke oil business seems to be growing in popularity and I am tempted to give it a try. Can someone experienced in these things please suggest how much and how often? I have seen figures ranging from 200ml to 300ml per tankful through to one or twice per year quoted - what works best please?

 
2010 110 XS USW (the slow one)
1960 Alfa Romeo Giulietta SZ (the fast one)
2005 Ducati ST3
1954 Sunbeam S8

Denis wrote:

Sorry for stupid question but has Castrol TDA same effect as 2-stroke oil?

Quote:

This has in the last two years gained a lot of momentum in Germany, after they started mixing 5% bio diesel with the normal diesel fuel. Now bio diesel in Germany is a mixture of raps seed oil and ethanol. This makes the concoction hygroscopic, i.e. it will absorb moisture (water!!!).

You now get an idea why there is such a high failure rate on VHP pumps and injectors on CRD engines in Europe.

This whole concept of mixing 2-stroke oil with diesel is nothing new. It started in Scandinavia and Northern USA among the fishermen' fleets in Winter.

But in our south african context, we first have to get a proper understanding about the quality of diesel:

1. Normal diesel is 500ppm sulphur content - Cetane - lower

2. Premium diesel is 50ppm sulphur content - Cetane - higher

3. "African countries diesel (Sadec countries and further north) can be anything up to 8000ppm sulphur content

If we now go back to the olden days of 10-15 years ago, it was not uncommon for diesel in SA to have a 3000ppm sulphur content. In those days one had to change the oil every 5000km as otherwise one ended up with a jelly like substance in the engine, also called the black death or sludge.

I am now going back to the topic at hand. The highest cetane rating in SA diesel is found in the Sasol 50ppm diesel. This 50ppm diesel (irrespective of brand) also has a reduced lubrication property which leads to defective injectors, see for example Toyota 3 litre bakkie engines.

In two-stroke oil we get 4 different quality ratings, which are based on the JASO (Japanese Automotive Standards Org.) scale:

JASO-FA very basic single grade SAE30 or SAE40 based 2-stroke oil (premix only)

JASO-FB Used for most premix industrial 2-stroke engines and scooters

JASO-FC "Low ash burn" used for separate oil injection and most outboard motors. this oil can be mineral or part synthetic

JASO-FD This is fully synthetic 2-stroke oil for racing engines. It is not suitable for mixing with diesel, because a) too expensive and b) not compatible with cats and particle filters.

For All Series LR and Disco1 and 2 a Jaso-FB rated oil is fine. For Disco 3 and 4 a JASO-FC rated oil has to be used, such as the Fuchs oil.

Now in order to provide better lubrication but at the same time also better power delivery from the engines, the ideal solution seems to be to add 2-stroke oil (see above) in a mixing ratio of 1:200 i.e. 500ml per 100lt diesel. This will increase the cetane rating by 3-5 points and will provide the following benefits:

1. Much better and more complete combustion (lower EGT)

2. Self cleaning of engine internals, as JASO-FC compliant 2-stroke oil burns cleaner and better than diesel. Due to this there is also about a 3-5% gain in fuel economy.

3. Sufficient lubrication of high pressure components in the diesel injection system.

4. Much quieter starting in the morning and smoother running

5. Reduced smoking

6. In engines with particle filter "burn free" action is reduced from every 600-700km to between every 1200-2000km

7. Much lower "clowd content" of diesel exhaust fumes typically from 1.5 down to 0.47. This is measured in Germany at the TüV.

8. Large government fleets in Germany report fleet reliability (MB Cdi, BMW CRD, Audi Tdi etc. etc. to exceed 400'000km WITHOUT VHP pump or injector failures

So the above deliberations give some well documented indication, why adding 2-stroke oil to diesel is such a clever move.

I run my 1999 Disco1 300Tdi on Sasol 50ppm diesel with a 1:200 mixing ratio of Sasol Corwa-120 2-stroke oil added. I get on long distance travel fully loaded between 8.9 to 10.8lt/100km depending on how heavy my right foot is. I have done a number of trips with 1000km per (standard capacity) tank.