80-10-10

The learning continues... such is life!
80% oil - 10% diesel - 10% petrol. This is my latest mix that gives good power & great economy. Starting is almost perfect and the glow plugs last well. Filtering to 5micron through onboard sock as fuel poured into tank. Loop option for return for starting, warming up or general cold ambient temps. The loop uses a circuit that allows bubbles to escape and works because of the height of fuel in the tank. It's abit hard to describe but kind of like a slim tall tank alongside the main tank that is itself vented. This allows bubbles to escape while still allowing warm/hot fuel to loop back. Please comment or ask questions.

Oil & petrol

Well oil has become more plentiful so I'm using petrol in a ratio of about 10% - 20% depending on things like temps and just how thick the oil is. All this without any added heat. I loop the veg while in warmup mode but after that there is quite often too many bubbles for looping the fuel line.

60/40dino is the ratio I've found to work reasonably satisfactorily, with only marginal reduced starting effectiveness from cold. All this with an unheated system. Ambient up to 20'C daytime. The internal IP pressure is giving its' best result yet with 11km per litre recorded at best. I've just bought a flat plate heat exchanger (fphe) so plan is to use that in the near future when more quantity of fuel becomes available.

Vege has become increasingly hard to find for free so I've resorted to blending 50/50 from a single tank with the usual sock filter in the top. I notice that the engine performs significantly better if the viscocity is more than straight dino. With my IP lift pump pressure gauge, an accurate reading can be obtained. By varying the blend ratio, I aim to keep the pressure within a certain range to maximise power and economy. With this set up it's going better than it has in a long time, though I'm having to buy the dino.

Startup tank review

I have made a separate plastic 20L startup tank with a 5micron filter socket in the top of it. This way I can do away with the troublesome paper filters. The return line runs into the filter sock. Problems of cross-contamination meant that the paper filter was occasionally becoming compromised so this modification addresses that issue completely. The whole system can now tolerate a small amount of fats now so filtering is not so stringent.

Cheap startup fuel

I now use no diesel to start from cold! The fuel I make up for this purpose is 20% Petrol /80% vege, plus 2% acetone. The vege should be completely fat free because no heat is used in the startup filter. This fuel gives marginally less power than diesel but who cares? There's a lot of confusion even amongst experts about the use of petrol in diesel engines. While the flash point of fuel that has petrol as part of the blend is lowered below ideal, the fuel cannot fire before the point of injection in any case! About 4 years ago, I drove nearly a year on blends including petrol. This startup blend saves a significant amount, costing currently approx 1/4 ~ 1/3 that of dino diesel.

Warning:
Don't mix petrol with diesel for use in a diesel motor because it's believed that modern diesel only has marginal lubricity. Adding petrol could serious compromise lubricity for the injector pump. The reason we can do it with vege is because it has plentiful lubricity.

Glowplug life

Another benefit of the additive/s mentioned earlier in this blog is the extended life of the glowplugs. I believe it was the buildup of carbon on the G.P. tips that hastened their short lifespan.