[bishopts]

I was thinking about water injection systems this morning, the main benefit is reducing the air charge temperature. Obviously water doesn't burn so adding water to the combustion cycle has negative effects. So adding ethanol to the water helps offset that. Another side effect is the water/ethanol mix cleans carbon buildup on intake valves while also steam cleaning all the lubrication oil off the cylinder walls.
So my thoughts were, could you use diesel in the place of water in a water injection system? Diesel is a really good parts cleaner and it lubricates at the same time. I dont know how quickly diesel can bring down air charge temperatures vs water. Usually diesel doesn't burn in gas engines so it could potentially lubricate the cylinder walls better but it could possibly fuel foul the spark plugs.

Obviously it would be a very low percentage of fluid conpared to the fuel amount, and maybe mixing it with ethanol like how the water setup is will offset plug fouling.

This is just a theory that i wanted to get some thoughts from you guys on.

[sscentex]

Sounds like something for the garage54 team to try out first.

[Spaceme1117]

That's an interesting way of thinking but I don't think so.

Diesel is closer to oil than it is to gasoline as far as ignitability. So injecting diesel into your gas engine would be similar to injecting motor oil. Your engine would be closer to a two stroke engine as far as emissions. Would likely significantly cut the life of the cats.

It's just much easier to add E85 to your gas with an E85 sensor and a tune to match.

[bishopts]

Originally Posted by Spaceme1117

That's an interesting way of thinking but I don't think so.

Diesel is closer to oil than it is to gasoline as far as ignitability. So injecting diesel into your gas engine would be similar to injecting motor oil. Your engine would be closer to a two stroke engine as far as emissions. Would likely significantly cut the life of the cats.

It's just much easier to add E85 to your gas with an E85 sensor and a tune to match.

I was thinking about oily residue making its way into the cat but since diesels do injection into the exhaust stroke for DPF cleaning and they have cats, maybe it would be fine. If you get the cat hot enough with fuel in it then it will become an incinerator. Which is kinda how it works already just in an extreme way.

[Vtor_ZL1]

Water injection is quite common and safe alternative to charge air cooling. Methanol is used often as well. Water is injected at high pressure and it more of a mist than a stream.


Post feels like AI troll.

[bishopts]

Originally Posted by Vtor_ZL1

Water injection is quite common and safe alternative to charge air cooling. Methanol is used often as well. Water is injected at high pressure and it more of a mist than a stream.


Post feels like AI troll.

That's a classic attitude of "do things like they have been done , for no reason beyond that's how they have been done"

[Vtor_ZL1]

Yeah you know, do things that works vs things that..... don't. I know, its hard concept to grasp.


What's your next plan... LOx injection ?

[bishopts]

Originally Posted by Vtor_ZL1

Yeah you know, do things that works vs things that..... don't. I know, its hard concept to grasp.


What's your next plan... LOx injection ?

When did it not work?
Have you tried it? Did it not work?

Water has zero lubrication properties just like methanol. But they are good at reducing charge air temps because of liquid to gas thermal transfer.

In theory diesel can do the same temperature transfer without stripping away lubrication from the engine.

I know it's a hard concept to grasp "thinking outside the box"

[sscentex]

Guess the real question is why? I've run water meth on my diesel's and currently my tundra and have never ran across an issue doing it.

In my head, the water is getting introduced on the intake stroke so the piston is moving down and wiping off the oil as it is and then the cylinder wall gets reoiled as the piston travels back up on the compression stroke so not to worried there.

There's also atomization to take into account. Diesel requires much higher pressure to atomize than water so you'd need a bigger pump and probably different nozzles.

Mixing the diesel with water isn't going to work as it's mixing oil and water. Probably some type of stuff you could put in with it to help with lubrication but not sure what.

[bishopts]

Originally Posted by sscentex

Guess the real question is why? I've run water meth on my diesel's and currently my tundra and have never ran across an issue doing it.

In my head, the water is getting introduced on the intake stroke so the piston is moving down and wiping off the oil as it is and then the cylinder wall gets reoiled as the piston travels back up on the compression stroke so not to worried there.

There's also atomization to take into account. Diesel requires much higher pressure to atomize than water so you'd need a bigger pump and probably different nozzles.

Mixing the diesel with water isn't going to work as it's mixing oil and water. Probably some type of stuff you could put in with it to help with lubrication but not sure what.

Very good points. I was thinking about the atomization of diesel would require a higher pressure and could possibly increase the temperature to the point it's not even helping

[bishopts]

Ive been thinking of alternatives to current systems for years. Like when carbon buildup on valves was at its worse for direct injection. I was thinking why not just put an injector at the throttle body that does maybe 10 percent fueling and back the injection duty cycle off to account for it. Even if it did a timed cycle based on load conditions similar to a regen for diesels. It would keep the valves clean and a healthy engine is a efficient engine.

[cthulhucaller]

Can you vaporize diesel under the types of pressure you can generate with a pump that would fit neatly in a car? I'm pretty sure that diesel, when injected using a very high pressure fuel system still enters the cylinder mostly as a liquid, but the latent heat of the cylinder helps finish the process. It's been a zillion years since I worked on anything with a diesel engine though. I might be dead wrong.

I'd also think that something as oily as diesel would leave a lot of residue or possibly pooling in intake manifolds, where meth or water just require a bit of latent heat to dry out and leave extremely minimal residue.

Either way, it's always interesting to try and rethink things.

[bishopts]

Originally Posted by cthulhucaller

Can you vaporize diesel under the types of pressure you can generate with a pump that would fit neatly in a car? I'm pretty sure that diesel, when injected using a very high pressure fuel system still enters the cylinder mostly as a liquid, but the latent heat of the cylinder helps finish the process. It's been a zillion years since I worked on anything with a diesel engine though. I might be dead wrong.

I'd also think that something as oily as diesel would leave a lot of residue or possibly pooling in intake manifolds, where meth or water just require a bit of latent heat to dry out and leave extremely minimal residue.

Either way, it's always interesting to try and rethink things.

like sscentex was saying, the pressures needed to vaporize the diesel would be very high, the only way to get that pressure would be to run an additional mechanical pump. then the pressures would make the diesel heat up to the point that its not viable.
gas could do it at a lower pressure but you would run into preignition issues. unless you used it for self cleaning and not performance gains. its a topic that never really gets enough attention. even meth injection is really under appreciated in my opinion. its such a simple modification that yields greatly.

[bishopts]

the two big drawbacks of water injection is cylinder washing and water is occupying space that could have been fuel\air. its pretty much splitting hairs as far as how bad it really is. but their has to be a better option.

and extreme example would be if you take a perfectly seasoned cast iron skillet and steam cleaned it. it would develop rust pretty quickly on the surface because the oils cooked into the metal would be stripped off.

obviously its not to that scale inside your on the cylinder walls but it is slightly. so finding another fluid that has the same benefits but none of the drawbacks wouldnt be a bad idea to look into.