Making Diesel Engines Burn Gasoline

[rbrowning]

Has anyone seen this article about the work at Argonne National Laboratory?

Making Diesel Engines Burn Gasoline | Autopia | Wired.com

[UFO]

They need to be careful of fuel lubricity in diesel injection systems. Gasoline is incredibly dry. Maybe they could add some biodiesel.

[Frank Lee]

UFO: read the article.

[UFO]

Originally Posted by Frank Lee

UFO: read the article.

I did that. My comment is based on this quote...

"Our approach is to use a fuel injector — in this case a diesel fuel injector — but use fuel that is difficult to auto-ignite. In this case, gasoline."

Diesel injectors require high pressure to inject directly into the cylinder, and these parts are immersed in the fuel. If it doesn't lubricate, the metal wears prematurely.

[Frank Lee]

Oh I see. It must not be a "traditional" or mechanical injector though, since they are talking about multiple injections per cycle.

[UFO]

I would think it's a common rail injector with a piezo-electric actuator. They run extremely high pressure, around 20k psi, and are very sensitive to lubricity. The new VW TDIs are common rail and are currently experiencing a ton of premature injection pump failures. VW is trying to blame the customers for mis-fueling, but the US spec diesel fuel is not as lubricating as the EN spec, which the TDI CR is designed for.

At any rate, I think you could add about 5% biodiesel to pump gasoline, get a seriously lowered octane and highly lubricating fuel that might work well in this application.

[rbrowning]

"The new VW TDIs are common rail and are currently experiencing a ton of premature injection pump failures."

A friend of mine is a retired GM mechanic and he told of a TSB that came out for the GM diesel back in he 80's. They too were having a lot of injector problems and were tired of replacing injectors that worked fine back in the lab. Their direction was to run a quart of ATF through the engine before testing. He said that it "cured" about half of the problems. The ATF provided detergent to clean any stuck on deposits and enough lube to keep the injectors from sticking. He said that he has done it to 100's of FE gas engines since and that it usually solves the injector problem. Just FYI.

[autoteach]

are they not using direct injection nozzles in gas HCCI engines already?

[Duffman]

Scania has been making a ethanol fueled engine that runs on the diesel cycle for some time now.