Fuel Heater Good or Bad?

[dennis]

A while back I had a customer with a mid ninties Mercedes converted to run WVO. He had a home made system which had killed his pump. Anyway he claimed that once while traveling that he had filled his WVO tank with regualar diesel. The tank was heated as was his fuel filter, and hoses. He said that the car really ran well on heated diesel, so I have been contemplating making a fuel heater with a Mercedes gasser fuel cooler which is just a coil of tubing that the gasoline runs through within a section of the Mercedes A/C refrigerant low side hose coming out of the evaporator for cooling, and coupling it into a heater hose on my Caddy and also my Volvo. Didn't see anything in the FAQ on the subject. I am not an expert but it seems to me that heating the fuel would aid in combustion.
Anyone have an opinion?
Dennis

[clbanman]

Well, we offer a fuel heater as an option on trucks that get shipped to Siberia, Khazakstan, Fort McMurray, etc.   BUT, Cummins and Detroit make fuel coolers standard on their engines.  Some heat is good in certain situations, but too much heat is no good.  Every engine is designed to run at it's best with fuel of a specific viscosity.

[dennis]

Hmmm. I may experiment. I do run some filtered waste motor oil / trans fluid mixed in my fuel because I usually have a lot of it on hand. I also have a container of clean stuff that consists of drippings from empty containers I just pour in. It would be easy enough to vary the temp, and moniter it.
Thanks for the reply.
Dennis

[bajacalal]

I found one of those small fuel heaters on a Mercedes engine at the junkyard (I got it free because they didn't know what it was and I posted about it here). I think heated diesel would help, to a point, as diesel fuel doesn't do well at cold temperatures. Heated diesel might be a good idea for an older, mechanical, IDI engine operated in the winter somewhere like Colorado or the midwest U.S. but I don't think it would do much in a warm climate and may even be a bad idea as the diesel get warmed by ambient engine heat. Where did this customer live at the time?

[gldgti]

maybe his heated diesel just ran really well compared to the WVO he was running just prior...

[dennis]

I found one of those small fuel heaters on a Mercedes engine at the junkyard (I got it free because they didn't know what it was and I posted about it here). I think heated diesel would help, to a point, as diesel fuel doesn't do well at cold temperatures. Heated diesel might be a good idea for an older, mechanical, IDI engine operated in the winter somewhere like Colorado or the midwest U.S. but I don't think it would do much in a warm climate and may even be a bad idea as the diesel get warmed by ambient engine heat. Where did this customer live at the time?

He said he was traveling from Florida to Tennessee

[jtanguay]

you need to accurately heat/cool the diesel fuel. unless you can properly cool it, then forget it. the diesel should be between 145-155 degrees F. you also need to consider that the way the system works now is going make it very difficult to heat/cool the fuel properly. the diesel engine burns very little fuel to run, but flows much much more than it needs for cooling. thats where a closed loop setup comes in handy. instead, the fuel return gets dumped back into the fuel intake, and in that loop is the fuel inlet from the tank. a check valve should be added to make sure you don't get reverse flow back to the tank, but the ideal setup is to have a small pump feeding the closed loop so the pump doesn't starve of fuel. heating/cooling mere CC's of fuel is much easier to do and i've been looking for an efficient way to do it with thermoelectrics. the only problem is designing a MOSFET controller that is capable of handling 25 amps of DC power at 12-15 volts.

[dennis]

you need to accurately heat/cool the diesel fuel. unless you can properly cool it, then forget it. the diesel should be between 145-155 degrees F. you also need to consider that the way the system works now is going make it very difficult to heat/cool the fuel properly. the diesel engine burns very little fuel to run, but flows much much more than it needs for cooling. thats where a closed loop setup comes in handy. instead, the fuel return gets dumped back into the fuel intake, and in that loop is the fuel inlet from the tank. a check valve should be added to make sure you don't get reverse flow back to the tank, but the ideal setup is to have a small pump feeding the closed loop so the pump doesn't starve of fuel. heating/cooling mere CC's of fuel is much easier to do and i've been looking for an efficient way to do it with thermoelectrics. the only problem is designing a MOSFET controller that is capable of handling 25 amps of DC power at 12-15 volts.

I use some used motor oil for fuel so I was thinking that it would be a good idea to heat the mixture to reduce vicosity somewhat. I was intending to use a heater water valve to vary the coolant flow through the heat exchanger, and mount a temp sender on the coolant return side to monitor the temp. Shouldn't be difficult to maintain 150 degrees or so.

[burnt_servo]

something to think about ...... the mercedes doesn't use a ve pump does it ?
so how does the internals of it's pump get lubricated ? ( i'm under the impression it is similar to a cummins "p" pump and is lubricated with engine oil ......but i could be way off with that since i have have never taken one apart yet ) .

the ve pump uses the same fuel it burns to lube the pump .

so if your run a thick fuel ( ie wvo ) too cold , or a thin fuel ( ie #1 diesel ) too hot your going to cause your injection pump grief .
so what fuel you run and and what temp your going to run it at needs to be carefully thought out if you want to keep it alive long term .

the other thing you need to find out , ..... is , ... is the fuel i'm going to use , going to  vapourize properly at the tempeture i'm sending it to the injectors at

which means pop testing the fuel at the intended temp though an injector and watching the spray pattern .

[janb]

Heated fuel would be good if you use WVO or Bio-D. (as is a fuel pressure gauge).
You can buy a Racor heated fuel filter.  These are essential on Sprinters (which use a fuel 'cooler' that complicates Bio-D usage in USA, since we have the crummy Soy stuff, as Europe buys all the good feedstock (Brassiere seed)).  They also warranty B99 unlike USA struggling to warranty B5   

[bajacalal]

maybe his heated diesel just ran really well compared to the WVO he was running just prior...

I'm thinking this...^

His car actually ran better on what it was designed to use rather than the poorly filtered, wet oil that he had been running in his craptastic, homebuilt heating contraption.

It does get kinda cold in the Southern states, sometimes.

[jtanguay]

you need to accurately heat/cool the diesel fuel. unless you can properly cool it, then forget it. the diesel should be between 145-155 degrees F. you also need to consider that the way the system works now is going make it very difficult to heat/cool the fuel properly. the diesel engine burns very little fuel to run, but flows much much more than it needs for cooling. thats where a closed loop setup comes in handy. instead, the fuel return gets dumped back into the fuel intake, and in that loop is the fuel inlet from the tank. a check valve should be added to make sure you don't get reverse flow back to the tank, but the ideal setup is to have a small pump feeding the closed loop so the pump doesn't starve of fuel. heating/cooling mere CC's of fuel is much easier to do and i've been looking for an efficient way to do it with thermoelectrics. the only problem is designing a MOSFET controller that is capable of handling 25 amps of DC power at 12-15 volts.

I use some used motor oil for fuel so I was thinking that it would be a good idea to heat the mixture to reduce vicosity somewhat. I was intending to use a heater water valve to vary the coolant flow through the heat exchanger, and mount a temp sender on the coolant return side to monitor the temp. Shouldn't be difficult to maintain 150 degrees or so.

check out my heater core thread and look at the heater core bypass valve. it would make a great valve to control the flow of coolant to the fuel... all you need then is a thermostat which is one that like (its mechanical, and is 0C to 120C