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heating fuel lines with 12 volts

heating fuel lines with 12 volts

heating fuel lines with 12 volts

(OP)
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?

RE: heating fuel lines with 12 volts

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

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

(OP)
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?

RE: heating fuel lines with 12 volts

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
    

RE: heating fuel lines with 12 volts

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.)

RE: heating fuel lines with 12 volts

(OP)
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?

RE: heating fuel lines with 12 volts

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: heating fuel lines with 12 volts

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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RE: heating fuel lines with 12 volts

In cold climates the winter diesel fuel is often much lighter than the summer diesel.
respectfully

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

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

RE: heating fuel lines with 12 volts

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

RE: heating fuel lines with 12 volts

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.

RE: heating fuel lines with 12 volts

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.

http://www.frybrid.com/test.htm

John

RE: heating fuel lines with 12 volts

My 1987 Ford F350 6.9 Liter Diesel had a 12V heater built into the fuel line leading into the filter.  Perhaps that would work for you.

RE: heating fuel lines with 12 volts

Check the heaters used to warm Nitrous Oxide bottles - they are mostly 12vdc w/ thermostats. ARC - Applied Racing Components in florida makes them

"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut."
-- by Albert Einstein

RE: heating fuel lines with 12 volts

Regarding using ATF in diesel - shouldn't be a problem in a private vehicle, but I understand that is used to dye the 'off-road' diesel fuel (less taxes) so if you get stopped (in the USA) and they find the dye in your tank, you could get fined. This came to light when someone accidently put ATF in the wrong bulk tank at a truck stop and a bunch of 18 wheelers had it in their tanks at the inspection station.
I think I'll add some just to lube the injectors and keep the bottle in the truck!

"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut."
-- by Albert Einstein

RE: heating fuel lines with 12 volts

I Have a 1998 Dodge 12 valve it has a built in fuel heater on the bottom of the mechancial pre pump. It is 300 watts and has a temp senser to turn it on when fuel temp. is 40 deg.
this shoul be avil. from cummings or Dodge

RE: heating fuel lines with 12 volts

I used to work in fuel storage and delivery for one of the big car manufacturers and then its component offshoot.
Colleagues and I spent a lot of time trying to get the management conscious of the development and component work needed to get diesel and biodiesel systems to work 'transparently', i.e. like gasoline systems. A lot of the problems came from serious misunderstanding of the range of qualities of diesel and biodiesels.

What you do need is/are:
1) a heated filter assembly (Stanadyne, Bosch + others)
2) a recirculation from the FIP outlet to the line from the filter to the FIP (uses the heat from the previously compressed fuel to warm the inlet fuel)
3) a thermostatic valve to redirect fuel down the return line once the temperature is much above 30degC (Bosch)
4) fuel line heater tape/wire and thermal insulation (WWW for info)
5) the return from the engine going right close to the fuel pick-up in the tank (SAE papers have info)
6) the fuel pick-up in the tank preferably being via a fuel delivery module, where a jet pump on the return line entrains tank fuel into a mixing reservoir with return fuel so the pick-up fuel is warmed. (SAE papers and patent publications have info)

Having put all this work into getting a reliable delivery system for diesel/biodiesel, you then have to be careful in hot weather.
In my development work on a 2.5l 100bhp turbocharged, non-common rail engine (Bosch VP44 pump), fuel injection pump inlet temperatures of over 90degC were experienced on a rolling road test at vehicle max speed, with simulated road speed air movement. Too much of this causes metallurgical failures of cams and plungers in the FIP. Then you seriously need to chill, as they say.

Bill



RE: heating fuel lines with 12 volts

vegoilboy - missed this off the previous post.....

Have a look at European patent EP1302711 for a diagram of such a system (Heaters, filters, thermostatic diverter valve)

RE: heating fuel lines with 12 volts

Parker Hanafin or one of their suppliers makes jacketed lines for handling JP at altitude.  They operate at migher voltage than auto volts.  I used the heated line er pipe to preheat CNG flowing into regulators and fuel rails and supplied PWM because it drew so much current that 22 gauge wire smoked.

It will take a lot of current at 12V.

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