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heating fuel lines with 12 volts

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vegoilboy

Automotive
Apr 25, 2006
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Does a 12 volt heat tape exist? Can 120v heat tape be modified for 12v? What size inverter is needed to use 120v heat tape from 12v battery? Is heat tape the answer?
 
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what are you trying to do?
If you put 12v through a 120 heat tape it will heat up but only 1/100 the watts Power=Volts*amps amps=volts/resistance
inverters are cheap, and a typically heat tape used for home plumbing is between 25 to 100 watts so the plug-in inverter will do the trick, but the battery will be dead in 10 hours not to mention the heat put out by the inverter
I am not to keen on heating a fuel line by any means
Hydrae
 
There used to be some OEM (GM diesel) and aftermarket 12 volt heaters that went in the fuel line prior to the filter to prevent wax clogging of the filters due to #2 diesel or poorly blended #1 diesel during cold weather. Check Standyne, Bosch, etc. to see if they have an off the shelf solution.
 
Thank you for your responces. I have modified my Ford F250 diesel to run on vegetable oil( no diesel). During warm weather there are no problems. When it is cold (below 30f)the veg fuel lines can gel. Are there any aeronautic fuel lines that are heated?
 
I was going to ask if you were running veggie fuel. Biodiesel is like diesel and doesnt need that BUT biodiesel is more comp;ated to make. I have heard of people using a glow plug to heat small fuel tank like a acuminlator used in gas VW's. I can not see how this would help the fuel in the tank, unless the returning fuel will warm the veggie fuel in the tank. Some setups use a fuel line inside on a water line from the readitor. I guess you know all of this too.

I would look for some find of restive setup like your think about and run it off 12v or 24v by passing the inverters loss in power output. I don't know how much it is, but it has to be some. I would think something like a waterbed heater would work under the tank, or the heater wire wrap in a pipe, rod in the fuel tank. If you run your fuel pickup line down into the tank you could wrap that, pur a few bends in it to make your wras longer if you need to.

24V's could be done with a second battery.
HTH
Richard
 
If it gels in the fuel lines, why doesn't it gel in the tank.

If it gels in the tanks, your fuel lines will need to be pretty hot. 30mm3 of fuel going into a cyclinder at full load and at 3000 RPM compared to 5mm3 idling at 1000 RPM is 18 times the flow rate, or 1/18 of the length of time to ungel it. You might be heating fuel for 18 seconds at idle and for only 1 second when running at load.

30F is below the cloud points of Soy, Yellow Grease and Tallow based biodiesels.

(I act as if I know all that, but I just read it! Now I'll have to read up to see what it means.)
 
Thanks for the responses! The internet is full of mis-information about the whole biodiesel and veg oil industry. After much research I was fooled into purchasing and installing a kit that did not work. Some people call 20% veg oil mixed with 80% diesel bio-diesel, other people consider boiling grease or yellow grease in lye for 30 minutes and then boiling for 30 minutes methanol and the remaining mixture. The result is called bio-diesel. My design is straight veg oil heated in the fuel filter housing, a small auxillary tank is heated, the fuel line has been re-directed to coil around the exhaust and muffler. The factory glow plugs heat the fuel in the heads.The truck runs great in warm weather, so I have until fall to figure it out.How do private and millitary planes keep there fuel lines from freezing when flying in the arctic?
 
I think the trick is to use a diesel no. 2 tank and switch to run before shutting down in the winter.

The aircraft I am familar with have carb heaters not what you need.

I noticed a veggie conversion ran the heater hose thru a heater core placed in the tank. It kept the conola oil nice and thin.

Cheers
 
Re aircraft. Some fly at 30,000 feet. It's fairly cold up there also, but they do not run on vegi oil, so fuel gelling might not be a problem due to the composition of the fuel.

Regards

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Jet fuel is specifically designed to be free of waxes and parafins so it won't thicken when cold. That's why aero-derivative turbines for power generation etc. often burn diesel fuel, but not airplanes. Even at the equator in the summer, at 30,000+ feet, its damn cold.
 
Aviation turbine engines burn a version of kerosine called jet fuel. Most people take this term as a high octane but it is not, the high octane fuel is for aviation piston engines. Jet fuel encounters the same problems as the vegetable oil and un-winterized diesel, it gels in cold enviroment. The US military requires it's fuel suppliers to pretreat all aviation jet fuel at the refinery. Commercial aviation fuelers offer a product called Prist. Prist contains additves for two purposes, prevent gelling at altituide where temps are very cold and prevent fungus from growing in the fuel tanks, lines and pumps. You can winterize your veggie oil or bio diesel blend by adding 1 qt. of automative gasoline per 5 gallons of fuel.
 
How are you heating your VO tank? I would suggest running radiator lines back to your tank, with tubbing running through the fuel tank to keep it warm. At the same time you could couple the fuel lines with the radiator lines, or perhapes run a the fuel line through the middle of a radiator line? This would preheat the tank, so the fuel is already warm, so the fuel line to the motor would not have to sustain as much heat because it's merely maintaining the temperature of the fuel instead of heating it up. Also, if you run your truck hard, this would help it cool off better with line exposure and heat dissipated into the fuel. If it still gets too cold, then get some of that pipe insulation from a hardware store, plus insulate the tank (obviously). Good luck, and let me know how it turns out. I'm looking into buying a dodge cummings which is (from what i'm told) a lot easier and cheaper to convert.
 
Jet fuel has the parafin refined out to prevent this very problem. And many, but not all have a oil-to-fuel heat exchangers.

as a side note, I have been told that jet-A runs fine in an automotive diesel application; if you add a cup of automatic transmission fluid to each tank. This is done to lube the injectors, which apparently the parafin content of diesel fuel provides.
 
I saw a chart once that listed many of the common injector pumps and indicated which ones would run on jet fuel and which ones needed the lubrication inherent in the diesel fuel and would fail running jet fuel.
Thanks for the ATF tip.
respectfully
 
Dispersants in the ATF will also pick up any water in the system and transport it to the filters where it is separated out and removed from the system, or if not, where it clogs up the fuel system.

I would worry about water in VO systems since my guess is that the vapor pressure is lower than even diesel fuel. Just a guess, however. If I am right, then one has to be even more vigilant regarding keep the tank topped up, especially overnight in climates that have a lot of humidity and go through the dew point often.

rmw
 
We build a small Heat Exchanger with a number of variations that is used to heat Vegetable oil or reclaimed veg oil using the hot water from the vehicle coolant hoses.

One of our customers has a neat control system that only allows veg oil into the fuel system when it is hot enough and also purges the fuel systems with clean diesel at the end of a run, all neat and automatic.

The system has been tested in europe with very good results, (enough for major road hauliers and bus companies to start converting their engines.

Europe is an obvious target for savings as our fuel prices are higher than the USA.
 
You may already know about this site. He makes a kit to handle biodiesel. He gives a pretty good explanation of how and why of heating the system. Maybe you can p/u some ideas here or buy a kit.
There are several sites on making biodiesel that explain how to take the soaps out to prevent jelling, also there are additives that supposedly will prevent jelling.


John
 
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