mndriver
curmudgeon extraordinare
Fuel economy is a measure of efficiency. Efficiency of the engine to convert chemical energy into mechanical motion by performing work. A typical engine is only about 78% efficient.
http://www.ehow.com/about_5089284_volumetric-efficiency.html
Modern diesels moved to improve efficiency by adding a turbo charger or a super charger to the engine to increase the air mass charged into the cylinder. More air allows for more fuel to be injected. Theoretically, able to achieve 105-108% efficiency. With modern computer controls, it allows for more efficiency and better fuel mileage.
But to GET all that efficiency, everything MUST work correctly. NO intake leaks, No exhaust leaks, engine compression leaks or fuel system issues.
Valves, injectors, CAC, Gaskets etc. All mechanical items that if they AREN'T right, anything else you do will likely never show whether it was even worth doing the item for in the first place. That would go so far as to include even how the driver disciplines themselves in operating the piece of equipment.
So in the game of fuel mileage, your equipment MUST be 100% to begin with to ensure you can start to even THINK about tweaking.
Modern production engines are sent down the road somewhat castrated. They need to be able to meet emission standards. If they can't they tune them so that they can. That's for the "general population" of operators. Basically, you can call it "drivability."
I'll leave more of that discussion as far as the mechanical stuff to other threads. My point of this posting is to discuss "additives". IMHO, I call them snake oils. And for good reason.
Fuel contamination and fuel system issues are mainly attributed to one of two items; external and internal.
External contaminants are like Water, dirt, chemicals etc. Some of it induced in the case of chemicals. Not all chemicals are good in a diesel fuel system. That's where you have things like a FASS fuel filter system, DAVCO or other spin on fuel water separator system put into place comes into place. My Series 60 Detroit calls for a 7 micron filter to remove the debris from the fuel.
Then you have an internal contamination. This is put into the fuel BY the engine. Oil, Coolant, carbon and asphaltene. Carbon, oil and coolant are all signs of bigger more major issues going on. Namely up around either the injectors or the fuel pumps. And it should NOT be ignored.
Asphaltene though is a bugger on its own. A tar-like substance that the modern engines make that wasn't really heard of in the older mechanical engines. Namely because it's created under heat and pressures that the old systems never saw that we now see in the common rail systems.
The best thing I have found for cleaning injectors IN the engine is this stuff. It's like $8-10 a pint and treats 250 gallons. Nor do you need to use a bunch ALL The time. Maybe once every year depending on how you run your truck.
Cummins Asphaltene conditioner.
http://www.cumminsfiltration.com/html/en/products/fuel/additives/asph_cond.html
Ashpaltene is nasty stuff. It's mainly the stuff that is sticky and gummy like that makes things like injectors NOT work like they are supposed to. And LOTS of people try to sell a product to claim they "clean your injectors." Some of it works, some of it doesn't.
Best way I have found to prevent injector fouling, don't IDLE your truck. All it does is recirculate your fuel when you don't need to. Aphaltene IS a normal by-product of just running your truck. It develops the more you run the fuel through your injectors. The asphaltene seeds itself and then starts to grow in size until it becomes an issue and starts to coat your fuel system from the inside out. The other way I know of to control your asphaltene load in your fuel, run your tanks as low as your dare run them. The lower the better. Get all the crud out of your system and let the filter DO ITS JOB. Partly why I LOVE my davco fuel filter.
This is where I though I was last November. I had a layer of crud inside my right side tank that was causing my fuel filter to plug in as quick as 75 miles.
Turns out, it was an Alge bloom. In November. I thought it was only a warm weather issues. It's not. It's also a cool (into Minnesota December temps even) weather issues as well. I have to flush my system with Emergency 911 for displacing water. Kill'em to kill the algae and Fuel system cleaner to clean the dead algae out of my tank.
But NONE of that could improve or change the physical property of fuel.
Remember what I said about volumetric efficiency up higher. Diesel fuel only has a finite amount of BTU's in it. Stuff like Biodiesel actual has a LOWER BTU content than dino diesel. Making the issue worse. More biodiesel, Less BTU content. Makes it even MORE important to know WHAT you are pumping into your fuel tanks.
super chargers and turbos are used to increase the volumetric efficiency of diesel engine. By using more air and fuel in the same space. You'd have to ADD 20% or more of the diesel BTU's injected into the engine with a wonder chemical with 1/5 the volume of the diesel to make it give you a 14% increase in fuel efficiency to go from 7 to 8 mpg in fuel mileage.
http://generatorjoe.net/html/energy.html
http://www.ehow.com/about_5089284_volumetric-efficiency.html
Modern diesels moved to improve efficiency by adding a turbo charger or a super charger to the engine to increase the air mass charged into the cylinder. More air allows for more fuel to be injected. Theoretically, able to achieve 105-108% efficiency. With modern computer controls, it allows for more efficiency and better fuel mileage.
But to GET all that efficiency, everything MUST work correctly. NO intake leaks, No exhaust leaks, engine compression leaks or fuel system issues.
Valves, injectors, CAC, Gaskets etc. All mechanical items that if they AREN'T right, anything else you do will likely never show whether it was even worth doing the item for in the first place. That would go so far as to include even how the driver disciplines themselves in operating the piece of equipment.
So in the game of fuel mileage, your equipment MUST be 100% to begin with to ensure you can start to even THINK about tweaking.
Modern production engines are sent down the road somewhat castrated. They need to be able to meet emission standards. If they can't they tune them so that they can. That's for the "general population" of operators. Basically, you can call it "drivability."
I'll leave more of that discussion as far as the mechanical stuff to other threads. My point of this posting is to discuss "additives". IMHO, I call them snake oils. And for good reason.
Fuel contamination and fuel system issues are mainly attributed to one of two items; external and internal.
External contaminants are like Water, dirt, chemicals etc. Some of it induced in the case of chemicals. Not all chemicals are good in a diesel fuel system. That's where you have things like a FASS fuel filter system, DAVCO or other spin on fuel water separator system put into place comes into place. My Series 60 Detroit calls for a 7 micron filter to remove the debris from the fuel.
Then you have an internal contamination. This is put into the fuel BY the engine. Oil, Coolant, carbon and asphaltene. Carbon, oil and coolant are all signs of bigger more major issues going on. Namely up around either the injectors or the fuel pumps. And it should NOT be ignored.
Asphaltene though is a bugger on its own. A tar-like substance that the modern engines make that wasn't really heard of in the older mechanical engines. Namely because it's created under heat and pressures that the old systems never saw that we now see in the common rail systems.
The best thing I have found for cleaning injectors IN the engine is this stuff. It's like $8-10 a pint and treats 250 gallons. Nor do you need to use a bunch ALL The time. Maybe once every year depending on how you run your truck.
Cummins Asphaltene conditioner.
http://www.cumminsfiltration.com/html/en/products/fuel/additives/asph_cond.html
Ashpaltene is nasty stuff. It's mainly the stuff that is sticky and gummy like that makes things like injectors NOT work like they are supposed to. And LOTS of people try to sell a product to claim they "clean your injectors." Some of it works, some of it doesn't.
Best way I have found to prevent injector fouling, don't IDLE your truck. All it does is recirculate your fuel when you don't need to. Aphaltene IS a normal by-product of just running your truck. It develops the more you run the fuel through your injectors. The asphaltene seeds itself and then starts to grow in size until it becomes an issue and starts to coat your fuel system from the inside out. The other way I know of to control your asphaltene load in your fuel, run your tanks as low as your dare run them. The lower the better. Get all the crud out of your system and let the filter DO ITS JOB. Partly why I LOVE my davco fuel filter.
This is where I though I was last November. I had a layer of crud inside my right side tank that was causing my fuel filter to plug in as quick as 75 miles.
Turns out, it was an Alge bloom. In November. I thought it was only a warm weather issues. It's not. It's also a cool (into Minnesota December temps even) weather issues as well. I have to flush my system with Emergency 911 for displacing water. Kill'em to kill the algae and Fuel system cleaner to clean the dead algae out of my tank.
But NONE of that could improve or change the physical property of fuel.
Remember what I said about volumetric efficiency up higher. Diesel fuel only has a finite amount of BTU's in it. Stuff like Biodiesel actual has a LOWER BTU content than dino diesel. Making the issue worse. More biodiesel, Less BTU content. Makes it even MORE important to know WHAT you are pumping into your fuel tanks.
super chargers and turbos are used to increase the volumetric efficiency of diesel engine. By using more air and fuel in the same space. You'd have to ADD 20% or more of the diesel BTU's injected into the engine with a wonder chemical with 1/5 the volume of the diesel to make it give you a 14% increase in fuel efficiency to go from 7 to 8 mpg in fuel mileage.
http://generatorjoe.net/html/energy.html
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