pre heated fuel

[Don Tanklage]

how much does it help?



seemed like my truck always ran better when pullin from the aux tank (huge shinny alum sittin the sun thing) than it did pullin from the stock (in the shade) tank



how much is heated fuel worth?



the answer will help me determine whether to build a fuel sys or just buy a fass

 

[cerberusiam]

IIRC, the optimum range of fuel temp is 80-120 degrees or thereabouts. Temp thins the fuel and makes it easier to inject and atomize. Better atomization leads to better burn cycles and more power generated per event.



Pretty hard to quantify just the fuel temp as there several other things that factor into making a difference. It does help some but I could not even SWAG on how much.

 

[Don Tanklage]

thanks



how warm do you think our first gen fuel is (w/o any other type of heater) by the time it reaches the ve?



i noticed they cast the filter adp right into the head and run the line from the filter to the pump on the motor side of the pump



thanks again



don

 

[PToombs]

Alot of the backhoes at work now have fuel coolers on them, in front of the radiator. Factor that into your theory!

 

[chuckwilson]

The hotter the fuel the less horse power you will have. Your truck probubly runs better because its plumed better than the factory tank is & if the tank is in the bed than it doesnt have to suck as hard to get fuel, (free flow) After 120 Deg. H. P. drops fast

 

[Don Tanklage]

we cool our fuel for the bikes



as in drain it all out after a run



fill it right before next run with fuel that is in a can that was just in the cooler



but thats race gas stuff, i got no prior exp w these diesel engines



thats why so many questions



and again, i really appreciate all the answers!



i live in so cal and i am gonna say cooler is probably better for me



it is hot enough under that hood



one more reason to stray away from the stock filter location and the stock steel line running BEHIND the ve



you guys are awesome

 

[cerberusiam]

Alot of the backhoes at work now have fuel coolers on them, in front of the radiator. Factor that into your theory!

Where does the fuel tank sit on these critters you are speaking about? Under a cover above an engine and hydraulic system running at a constant rate generating how much heat... ... . ????





The ones I have had experience with usually mounted the fuel tank where they got warmed extremely well. Not sure what has happened in the last 20 years though.



I "factored" that in. :-laf

 

[cerberusiam]

we cool our fuel for the bikes



as in drain it all out after a run



fill it right before next run with fuel that is in a can that was just in the cooler



but thats race gas stuff, i got no prior exp w these diesel engines



thats why so many questions



and again, i really appreciate all the answers!



i live in so cal and i am gonna say cooler is probably better for me



it is hot enough under that hood



one more reason to stray away from the stock filter location and the stock steel line running BEHIND the ve



you guys are awesome

Big difference between gasoline and diesel and their respective evap points. The main reason to cool gas is to keep its evap points down enough to get it to mix with the air charge. Gasoline has a lot lighter base then diesel so it does not take heat well.



Diesel is heavy enough and the molecules large enough it takes more to get it to break apart. In addition, diesel is almost always direct injected and not mixed with the air charge. Heating the diesel into an optimum range is supposed to aid atomization and power from the burn.



While it may be hot under the hood at a stand still, rolling down the road you will should not see more than 5-10 degrees difference from the ambient temp. Also, your fuel tank is a long ways from the heat of the engine and the air constantly flowing around it keeps heat soak to a minimum.



Unless you drive around in Phoenix where the temps in summer are 140-150 on the pavement, you may have to warm the fuel a bit to optimum levels :-laf, but THATS another whole problem.



Above and below the range I posted HP losses start occuring due to the lack of BTU's, combustion event length, and energy loss needed to warm the fuel. In that range there is not much difference. If it were me, I would leave the heater just to take advantage of every bit possible.

 

[Don Tanklage]

maybe the fass sys uses a heater because the filter is no longer screwed onto the cyl head, but now under the truck?



so if i was to relocate the filter not having a heater may be a problem



that is why i posted the ques



i heard someone mention a fuel heater but didnt understand why



maybe that thing you thought was a cooler was actually behind the radiator?



bet our fuel is a lot hotter than 120, even on a stocker



the fuel filter is always really hot to the touch when the motor has been running and think of how slowly the fuel must move thru it (cuz these trucks get good mpg)



oh yea, there is a return, forgot about that



has anyone put a fuel temp gauge on a 1st gen?



thanks



don

 

[JLEONARD]

The higher HP marine Cummins engines use a fuel cooler. I had one on my marine 270.

I don't have the spec sheets handy, but the HP rating is a little higher when the fuel is at a lower temp.

 

[Don Tanklage]

you cant both be right...



i have heard the term 'gel' when referring to diesel



stock filter is screwed onto the CYL HEAD



cummins ran the fuel line tucked right up against the motor



fass sys has a heater (so i have heard, dont know that for a fact)



factor those things in and it would seem they want the fuel warmer than room temp



have you ever replaced a fuel filter on the side of the road?



that sucker is warm



real warm (hot)



dont make me move the filter, replumb the truck, and get before and after dyno sheets



lol



and the survey said, "do it"



don



ps - one thing i do know is living in so calif there are lots of things the vehicles come with that they dont need. the conditions here are nothing like the conditions accross the majority of the country. (the heater thingy for the intake for example). maybe that is why they mount the filter on the head? maybe these things run like crud when you try to inj 32 deg fuel into them? bet they do. so come on, who is gonna dyno both ways? who is gonna install a temp gauge at the injector and start moving stuff around?

 

[cerberusiam]

you cant both be right...

Sure we can, it all depends on how the fuel systems are designed and the amount of heat soak the design contributes.



The FASS has a fuel heater option because plumbing around the stock canister is frequently done.



Injecting 32 degree fuel will cause LOTS of smoke and rough idling. Ever fire one of these beasts at 20-40 below zero and you will see that. :-laf

 

[Greenleaf]

I removed the heater from both trucks. For one, I don't drive in winter. They are a potential leakage point (one was) and the pulling tractors will sometimes use a fuel cooler.

 

[Don Tanklage]

so, with the ve mounted where it is and the radiator in front of it and all that hot air blowing on it is it safe to say that driving in 60 or better degree weather i would benifit from moving the filter to a cooler place and running the line up the frame rail and directly to the front top of the pump?

 

[Don Tanklage]

mr GL, plz respond



i just cant seem to find anyone that really knows about this preheating the fuel stuff



veggie oil has to be hot, i have learned that



but i am not gonna be running that stuff



this is from an article i found: "Not quite as sophisticated as their big brother, the inline 6-cylinder D4. 2L and inline 4-cylinder D2. 8L still offer electronically controlled fuel delivery. An ECU in the fuel pump monitors throttle position, turbo pressure and temperature, engine speed, injection timing, fuel temperature and injection pump position. Fifty times every second, the ECU processes this information and determines how much fuel to inject and when. "



they didnt go on tho



is it an emissions thing? (the hot fuel)



or does it help with efficiency too?

 

[PToombs]

Where does the fuel tank sit on these critters you are speaking about? Under a cover above an engine and hydraulic system running at a constant rate generating how much heat... ... . ????





The ones I have had experience with usually mounted the fuel tank where they got warmed extremely well. Not sure what has happened in the last 20 years though.



I "factored" that in. :-laf

Fuel tank is in front of the rear tire, left side. It's what you step on to get in. Most newer 'hoes have the tank here, on one side or the other.

 

[PToombs]

Don, the heater in the stock or FASS systems is for cold weather use. The fuel can "gel" at low temps. The "heater" raises the fuel temp to help prevent gelling, and to help in starting.



I wouldn't spend the time and money to move it for heat issues. The reasons I would move it are,

Want/ need more filtration (bigger filters) that won't go in the stock position.

Want/ need aftermarket pump for more flow. Need new location.

 

[Don Tanklage]

i am going with cool fuel



huge 6 micron filter to be mounted under truck, elec pump mounted down there too, and running the line up the frame rail and right to the ve



will let you know if it picks up or falls off



will check both, power and efficiency

 

[Don Tanklage]

opps, i was posting that right as you were posting your second post



the larger filter is gonna be nice



no matter what

 

[Don Tanklage]

found something:



From Mike L



What we have found is that the fuel is being returned to the tank at temperatures starting at 130 degrees. On hot days, towing heavy, heavy throttle applications, long road trips, and stop and go driving (aka normal driving) we have seen temperatures well into the 170+ degree range. There are those out there that have written that there is less soot production, which is true, at higher fuel injection temperatures. But there is also viscosity breakdown of the fuel which leads to poor atomization upon injection. If you will look at your fuel system from start to finish you will notice in the stock system that there are many places for the fuel to pick up heat. After leaving the frame rail it comes up by the transmission and across the lifter valley working its way in some applications to the FICM to act as a coolant. Then it is run through the fuel filter which sits directly above the exhaust manifold and on into the CP3 where it see's compression up to 23-26K psi. Which we all know pressure equals heat. After making a run to the injectors the unused fuel is then returned via lines that run through a hot oil bath under the valve covers and through the lifter valley. On the return trip you will notice an extremely inefficient stock fuel cooler before returning to the tank. Upon replacing the stock cooler with the new Fuel Cooler all vehicles tested immediately saw a 2-4 MPG increase. Just from keeping the fuel at ambient temperatures in the tank. We have an optimal number for injection but it would be next to impossible to maintain with all of the heat adders that I have pointed out above. The next best thing we have found is ambient or as close to ambient as possible for the fuel leaving the tank.



There are things we don't know yet about the possibilities of cool fuel in diesels. This has been a study of mine for 3 years. I have called knowledgable people around the world and asked a simple question. " What is the optimum fuel temp in a diesel?" I got answeres from; the hotter the better, or it doesn't make a difference. Quite a few knowledgeable engineers said they really never looked at it that close. The basic answer was "I have no idea " Is there such a thing as optimum fuel temp? I don't know. The best down to earth information I have recieved so far is from Cummins Marine division. It shows the fuel temp coming out of the engine at 150F and into the water heat exchanger with an out temp at 75F. Is this the optimum temp? I still don't know , but it satisfies Cummins and I now use this number as a goal. I am still learning but am convinced I am on to something and I see results.

The 2 fans draw less than 4 amps so it will not draw much from the alternator. Fans can be cut off at will with a switch. As`far as winter weather; I have not tried it but the fuel in the system will still get hot and the lower the fuel level the hotter your fuel will be. I do not believe our oem fuel cooler is enough and you can test for yourself by touching both the inlet and outlet lines at operating temps coming out of the cooler. If you try same test with mine you will see a difference.

At this point I do not have an answer for my cooler protection in offroad use; sorry, not there yet.



obviously a 2nd or 3rd gen driver but he sounds like me



lol