Biodiesel Heater System - revisited

RareAir_Biofuel

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Denver, CO
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'03 Jetta Wagon
OK, I posted something on this months ago, and since I didn't have much to say then, the post got ripped down. I'm back with the final results here... by the way, car is '03 Jetta wagon.

In the beginning, I was thinking of heating the whole system (tank, lines, filter, etc) like a SVO car. After looking at the power requirements for electrical and the amount of hoses etc for coolant heat, plus $$$$, those ideas crashed. So we spent some time pinpointing the problem to attack it directly. Figuring out the problem involved = run high % bio, freeze car up, and then figure out where it froze. Not too scientific, :rolleyes: but it worked. The biggest help to this has been the procycle clear-blue lines I have under the hood. I found that the filter was NOT the problem - car starts, runs for 1-2 mile, then stalls out. I could see that the filter was moving fuel to the engine, probably because it gets so much heated return fuel from the engine (I've heard 9/10 of fuel goes right back). The problem, at least in my car and I would expect in many other TDI's, is further back. The filter was just not getting fuel. So it was the fuel line or the tank that was clogging. After another freeze-up, I took off the cap to the fuel sender unit, shook it around to knock off bio ice crystals, and poured some PS right down in there. Car ran like a dream after - turns out the problem is in tank.

Solution: got a heater element from PlantDrive
http://www.plantdrive.com/shop/product.php?productid=16148&cat=250&page=1then
Its a 12V element made by Racor, pretty simple design. Only takes a couple of amps, 85 degrees tops, not too expensive either. We figured theres no point in heating the whole tank, might as well get it right where its clogging - the sender unit screen. We imbedded element sideways in the platic box that the screen is carved into (pics to come, can't figure out how...) to put the heat right where the fuel enters the sender.

The switch to control the element went on the dash, where the ESP button is on nicer models. Plugged it right into the fuse box w/ the map light fuse. No worries about shorts that way.

To make sure the heated fuel gets to the engine, we replaced the crappy plastic fuel line with some Goodyear 3/8" insluated line. 3/8 was probably overkill, I'd use 5/16 next time, but the fuel seems to move to the engine much smoother now.

Total cost:

element: $55
fuel line: $25 for 25 feet, we used probably 10, but had to buy a whole roll.
Labor: not to hard to do it yourself, would probably take a day or so. I got SligShotSlug, an SVO conversion company here in Denver to help, since I'm not the most mechanically inclined.

Pics to come as soon as I figure out how, and I'll try to post updates on its effectiveness. I figure I can run B75 when its 40+ during the days (no garage or I'd be running B100), and B50 when it gets really cold.

EDIT:

Finally got some pics up, see at http://biodieselpictures.com/viewtopic.php?p=624#624
 
Last edited:

RC

Top Post Dawg
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Oct 13, 2000
Location
Maryland`s Eastern Shore
TDI
Two White 96 B4 Wagons
Nice work, looking forward to the pics. I've always known the fuel sending unit to be a bottleneck but am reluctant to go to measures beyond winterizing our fuel to B80.

Sad thing is, car manufactrers could offer a foolproof OEM fuel heating system and option it for about $100. Insulate and heat the tank, fuel lines, and filter and we're on our way. Perhaps one day.
 

bluegraphite

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NH
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JettaWgn5spd 2005 bluegraphite; 2000 Jetta TDI GLS
That sounds great! Can't wait to see the pictures.
Can you show how & where you made the junction to insulated lines from the sendng unit, too? It's a pretty tight fit back there, as I recall. Does the larger line make the bends without kinking?
 

sonicyellow

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Jun 28, 2006
Location
New Hampshire
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Silver '03 5spd Jetta
This is exactly what I've been looking for. :) Anyone know of a company that would do this sort of thing in New England?

Now, what's the possibility of setting up a timer and thermometer so it'll run a little before your usual drive time *if and only if* it's below a certain temp outside? Being able to automate this is key here so I can convince my buddies to go bio, too. They're a little lazier than I :D.
 

RareAir_Biofuel

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Location
Denver, CO
TDI
'03 Jetta Wagon
Jury's still out on the fuel line issue - I don't know if its as big of a problem as people say. I think when biodiesel causes problems with a hose, the hose is already cracked internally or of poor construction. We went with the Goodyear since 1) its some of the best hose made, 2) its insulated, unlike the polyurethane hoses, and 3) is a heck of a lot cheaper than Viton. Installing it took less than an hour, and a new hose would be easy to put in if this one starts sweating. Big improvement over the OEM hose, thats for sure.
 

RC

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Maryland`s Eastern Shore
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Two White 96 B4 Wagons
RareAir_Biofuel said:
... We went with the Goodyear ...
I've got a big Goodyear supply hose on our 500 gallon storage tank. It's been pumping B80/B100 for 7 years now... sweating the last two or so but still holding up quite well. We'll see how long before I have to replace it.
 

Jeffmx5

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Dunstable, MA, USA
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Did you replace the elbows?

When you replaced the stock fuel line did you eliminate the 90 degree elbows as well?

I have had similar experiences as you. When I investigated where the problem was I also observed that the fuel filter was not the problem. I tested trying to pull fuel from the sending unit and I did have success there. When I tried to pull fuel through the line I found that the line was plugged. I blew the clog out of the line and from the results I believe the clog occured at an elbow.

In my opinion, in order to cold start with bio the first issue is making the cold bio fluid enough to even start. After that the next problem is getting the cold fuel to flow from the tank to the motor. Any locations that can collect frozen particles will quickly cause a clog. The fuel screen, check valve, and elbows have proven to be problem locations.

I like your idea of heating the fuel at the fuel sending unit, but the initially cold fuel in the line still has to make it to the filter without plugging. Replacing the 90 degree bends with more gradual radius curves should allow slushy fuel to still flow to the filter. I would replace the return line and drill out the return check valve for the same reason. Intially this fuel will be cold. The hot return fuel must push the cold fuel back to the tank. The cold fuel in the line could still plug at an elbow or check valve.

In one test I performed it took over 5 minutes of driving for the reported fuel temp in VAGCOM to climb from -10C to 0C due to the recirculating heating alone. Assuming the cold fuel in the line makes it to the filter without plugging then the heated fuel from the heater in the sending unit should keep the filter from plugging and speed up the heating of the filter.

The pump at my local retailer of bio has frozen up so unless we have an above freezing day I will have to run D2 for the rest of the winter. :(
 

sassercollins

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here and there
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2000 Beloved Golf, 4 Door, MK4 (AHL)
Yeah Mon!
You saved me a ton of research. The weather is cold here in Idaho and we can't aways find Canola stock, which tends to hold it's own in the cold weather. I heard linseed does really well too but I have not found any in the recycled market.
I had been looking for a back-up heating system. Thanks for the post Rare Air!
 

Huweth

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Devon, UK
TDI
2001 Passat TDI PD Sport
I've heard of a few people here in the UK who have installed insulated electric heating all along the fuel lines. It works like an electric blanket. They switch on before they start, wait a short while for things to warm up a touch, then start the engine and leave the electric fuel line heating on for a few miles to allow the fuel plenty of chance to warm due to the electrical and engine heating.
This was a long time ago, and I think it was for running BioFuel as opposed to Biodiesel, but would of course be great for BD in the cold.
Anyone heard of this or done it?
 

RareAir_Biofuel

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Denver, CO
TDI
'03 Jetta Wagon
Answers to 2 questions:

RC- Denver Biodiesel, the local co-op, also has a big 'ol Goodyear fueling hose, which has been in operation only 6 months but looks to be doing a solid job. Bought on recommendation from several experts.

JeffMX5- yes, the line does repace all 90 degree elbows except the one right at the top of the fuel sender unit. The only place this gets sticky is where it has to go from the top of the fuel tank to under the car. We had to use an uninsulated poly hose for this part, it was the only thing with an O.D. small enough to get through there. If you were OK with cutting a piece of the body sheet metal out (hidden from view by the back seats), you could run as big a hose as you want without kinking. Up front, the fuel line goes through a ~2x3 inch housing that makes a nice easy bend up to the engine. No problems pulling hose through there. Overall, flow is great, which should make life easier on the injection pump (TDI's are on a vaccum system, no fuel lift pump).
 

MrErlo

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Omaha, NE
TDI
2003 Golf 4dr 5sp
excellent research Rare.

i've been reading posts about fuel addatives and heating systems for a while, this one seems pretty good to me. i want to run B100 year round so i'm gonna need some a pretty hard core heating setup.

i notice you're in Devner and you're got the SVO company to help you out. if i were to take a weekend trip up that way, would you be willing to teach me the process you used? we've got the Kansas City GTG coming up at the end of March and i'd love to be able to teach this mod to people there.

let me know if a weekend workshop would work out for you, thanks.
 

RareAir_Biofuel

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Denver, CO
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'03 Jetta Wagon
Sure thing Mr Erlo. We could run it through Denver Biodiesel, the co-op that holds all of these factions together. I'll bet Kirby at SlingShot Slug, the SVO guru, would be happy to explain the systems. You can give him a call at (303) 435-7479.

That said, my system is rather simple, and wouldn't hold up to more that B50 in these Colorado winters (below 0F ~10 nights a year, and 10-30 most of therest of the winter). To expand on the system I have, a filter heater by Racor or Stanadyne would complement nicely, and can be run off the same circuit. The beauty of these systems is their tiny energy draw, they don't require a second battery/plug ins. Using the hose for insulation helps utilize the heating power of these tiny elements. Kirby has some systems that are way better, B100 all the way!

**Still trying to figure out how to post pics, any help there???
 

Jeffmx5

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Calculations

I was curious so I got out my physics book this weekend and performed some math.:eek: I am an Electrical Engineer so this was actually fun :rolleyes:.

I have seen several heaters for 12V systems that dissipate 100W. I was curious how quickly that would raise the temperature of the fuel. I was able to find the specific heat of D2 on the web and I assumed bio has the same specific heat.

I started with an assumption for maximum fuel flow rate. I assumed traveling at 90mph and achieving 34mpg while doing it. This equates to 10 liters per hour of fuel used. 100W for 1 hour is 360kj. This will raise 10l of fuel by 21C. ( I have skipped a bunch of interviening math )

90 mph in the dead of winter is unrealisticly fast for me so I took a more typical case. 60mph and achieving 45mpg. This equates to 5l/h and therefore 42C rise.

If the starting temperature is -40C then a 100W heater will heat the fuel to 2C (above or at the cloud point of bio) under normal highway conditions.

Now what about idle or low volume usage? I don't know what the fuel usage is at idle but I believe it is reasonable to assume it is at least 10 times less than steady state highway speeds. 0.5l/h would give a 420C rise.:eek:

This shows the need for a thermostatic control built into the heater. If a 100W heater is installed in the fuel tank then convective circulation should keep the element from overheating until all the fuel in the tank is too hot. Another concern with an in tank heater is what happens to the heater when the tank is low on fuel and sloshing uncovers the element for a moment. The element must not be allowed to get hot enough to ignite the fuel when it sloshes back. In the confines of a fuel filter a 100W heater element is only cooled by the fuel flow over it. At idle the small volume of fuel flowing over the element will over heat very quickly if the heater runs at full power.

This is why companies like Stanadyne have a thermostatic control built into the heating element. Any electric heating element you add to your TDI must have a thermostatic control built in otherwise you run the very real risk of starting a fire.

Based on the expected flow rates of our TDIs 100W heaters appear to be appropriately sized. At 50W there might not be enough heat rise at highway speeds to warm the fuel enough.

This analysis does not take into account the heat of solidification (the heat required to melt frozen particles). If there is some crystalization in the fuel (clouding) the heat required to melt that crytalization will reduce the resultant temperature rise.

Jeff
 

RareAir_Biofuel

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Denver, CO
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'03 Jetta Wagon
Thanks Girl Mark, I will give that a try- working on a login for biodieselpictures.com. By the way, all of us at Denver Biodiesel are excited to help out w/ the B100 conference this summer. We'll work to make sure it goes off with a bang.

mx5 - I'm not sure what to say there - I think the element is way less than 100W, and its right in the main mass of fuel. I was worried it wouldn't put out enough heat, not the other way around. We had some freezing issues at Denver Biodiesel, and w/ a 300W heater in the 250-gal tank its taking days to melt off anything...
 

Jeffmx5

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Since you are using a commercially made product I believe you will be safe. I have read posts where people have "rolled their own". It is these members for who I am concerned.

There are some heating elements that must be submersed in fluid or else they get too hot and burn themselves out. Many electric water heater elements have this issue.

As a test for yourself wire your heater to the battery and place it on a non flamable surface. See how hot it gets. If you drip some D2 on it does the oil self ignite or even smoke?

With the heater fully submerged in oil the oil will circulate through convection and keep the heater element cool enough.

As an Engineer most anyone can design a solution that will work in the steady state normal operation. It is the start up, shut down, transient cases that cause failures. You need to think of all the oddball but normal conditions and what effect they will have on your design.

With the tank full of cold fuel it will be fine. What happens as the tank nears empty? What happens as fuel sloshes back and forth in the tank when it is nearly empty? If you are driving up or down a steep hill so the fuel uncovers the element for many seconds what will happen? Does the heating element get hot enough to melt the plastic it is mounted to in this case? If the fuel temperature is below the pour point so it does not flow what happens? Does the fuel right against the heater get over heated because it cannot circulate away from the element? What happens if you forget and leave your system on in the summertime?

These are all real possibilities. You must understand what your design will do in these conditions and if that is acceptable. You have a source of heat, fuel, and oxygen. If something goes wrong the consequences could be dire so you want to be sure the system is safe.

In my opinion you want to make the system as fool proof as possible. You don't want to have to remember to have to do anything. I would wire the power so that the element is only on when the ignition is on. That way you cannot leave it on over night and drain the battery down. If the element has a thermostat built in then it cannot get too hot (unless the thermostat fails closed).

Heating systems that use engine coolant as the heat source cannot start a fire because they cannot get hot enough. The down side is they are more difficult to install and they don't provide any heat until the engine is warm. By then you could be stuck with frozen fuel. The eletronic heaters work immediately so you are less likely to get stranded a mile down the road.

250 gallons is 950 liters, almost 1000 liters. If it takes an hour to heat 10 liters 21C with a 100 W heater, it will take 33 hours to heat 1000 liters 21C with a 300W heater. This does not take into account the heat required to melt any frozen fuel and any loss of heat from the tank due to convection of air over the tank, conduction due to soil contacting the tank or radiation. Yup 300W is not a very big heater for 1000 liters of fuel.

I don't mean to dissuade you from adding an electronic heater. I like the idea and want to try something similar myself. I did the calculations to see how effective the heaters available would be. Since I went to the trouble I figured I would share the results. I think 100W is in the right ball park but some measure needs to be taken so that it cannot get too hot.

Let us know how your system works out.

Jeff
 

MrErlo

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TDI
2003 Golf 4dr 5sp
Jeffmx5,

it seems as though your plan calls for the in tank heating element to be engaged the entire time your car is on. in my undertanding, fuel that is not burned is recycled from the IP back to the tank. so after the engine has reached NOT, won't the recycled fuel provide more than enough heat to keep the fuel in the tank warm? that would allow you to shut off the heating element as after 5 mins or so, which would help avoid many problems. this is just in regards to your calculations about "maximum fuel flow rate", since by the time you get up to 90mph you're generally near NOT anyway.

perhaps i'm not undertanding the fuel system correctly, i'll apply liberal amounts of the search function to inform myself. your insight is very much appreciated, you seem to have given this issue very careful thought. i'll make sure to keep all these things in mind.

also, you mentioned " Heating systems that use engine coolant as the heat source". i've considered the idea of installing a FrostHeater (TDIHeater... whatever brand name you want to call it) and plumbing it not only into the coolant system, but running additional pipe around the fuel filter. that way you can plug in over night and keep the engine warm as well as the fuel in the filter, which should make for much easier starts in cold weather. how do you feel about that idea? do you think it would be easier/wise/cheaper to just install a FrostHeater and Stanadyne heated fuel filter seperately?
 

Huweth

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Devon, UK
TDI
2001 Passat TDI PD Sport
What about plumbing the coolant back to the tank and filter and installing a supplementary electric water pump and heater that would warm the coolant below a set temp and pump it all around to keep everything at an acceptable temp?
 

Bill_Blazek

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Location
Littleton, Co
TDI
2002 Golf GLS TDI, 5 spd, Navy Blue
Huweth said:
What about plumbing the coolant back to the tank and filter and installing a supplementary electric water pump and heater that would warm the coolant below a set temp and pump it all around to keep everything at an acceptable temp?
This is exactly what I am planning on doing with Kirby whenever he has time.
We have a design for running a loop of tubing with cooant along the
fuel lines, back to the tank, and an aluminum tube into the fuel sender.
The fuel and coolant lines will be bundled in insulation under the car
so the fuel lines will be warmed all the way from the tank.
And the aluminum tube in the sender will warm it.

My goal is just to warm the lines and sender enough to keep fuel flowing
from the tank and not gel solid in the fuel line and block the flow of fuel.
I have another coolant based fuel heat exchanger and
an electric fuel line heater in the engine compartment that
heat the fuel to ~100+ and thoroughly ungell it before it gets to the filter.
 

GV-TDI

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Dec 28, 2006
Location
Grass Valley, CA
TDI
2000 Jetta
Take a look at PlantDrive.com for fuel heating systems. They do WVO systems and from what I've seen on their website, they have an edge over the GreaseCar systems. Mostly, their heating systems are electrical oriented although they can provide coolant-based heating systems as well. If I remember correctly, they have a temperature regulated as well. Unfortuanately, their products aren't inexpensive and a basic Jetta system is in the $1400 range. Still, the parts are mostly individually available.
 

Jeffmx5

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Mr. Erlo - I put together a response to you but in the process of posting it something bad happened and it didn't get posted, I don't know why. I will put the information together again in a few days and try posting.

Jeff
 

thenewguy

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Oct 26, 2006
Location
Baltimore
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2012 TDI Sportwagen, 2000 Jetta GLS TDI
I was just looking at the GreaseWorks! website, and they offer a B100 winterization kit. It looks to be a fuel filter heater, and a tank heater for $150. Does anyone have experience using these? Here is the link. They also have other heating options, line heating, etc, and they have a Viton fuel line kit for VWs as well.

http://www.greaseworks.org/index.php?module=pncommerce&func=itemview&ItemID=65
 

MrErlo

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Omaha, NE
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2003 Golf 4dr 5sp
from Arctic Fox

thenewguy said:
Does anyone have experience using these?
i don't have any expereicnce with them, but i did some research on the Arctic Fox site.

as specified by GreaseWorks!
Specs: 12v Arctic Fox heater pad, 8" x 1.5", 80 watts, 6.2 amps.

and from the Arctic Fox online purchasing page

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]AF-EH-2874[/FONT] [FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]ELECTRIC FLUID RESERVOIR HEATER 8''X1.5'' 80W 12V (View)[/FONT] [FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]$58.05[/FONT]



Specs: 120 volt, 250-watt, ~2 amps, 3.5" x 4.5"

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]AF-EH-2802[/FONT] [FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]ELECTRIC FLUID RESERVOIR HEATER 3.5''X4.5'' 250W 120V (View)[/FONT] [FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]$80.94[/FONT]

so it seems like it might be slightly cheaper to just buy from Arctic Fox directly.
 

MrErlo

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Location
Omaha, NE
TDI
2003 Golf 4dr 5sp
lift pump

what about wiring a lift pump and heater combo? i've been considering the lift pump anyway, but i'm not quite sure how well the two would work together.

anyone have thoughts on that?
 

Bill_Blazek

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Location
Littleton, Co
TDI
2002 Golf GLS TDI, 5 spd, Navy Blue
thenewguy said:
I was just looking at the GreaseWorks! website, and they offer a B100 winterization kit. It looks to be a fuel filter heater, and a tank heater for $150. Does anyone have experience using these? Here is the link. They also have other heating options, line heating, etc, and they have a Viton fuel line kit for VWs as well.

http://www.greaseworks.org/index.php?module=pncommerce&func=itemview&ItemID=65
The Greaseworks site says:
greasworks said:
Specs: 120 volt, 250-watt, ~2 amps, 3.5" x 4.5". Self-adhesive pad heater with special 3M adhesive backing, designed to adhere to all bare metal surfaces. Heater is wired with a standard 3-pin 120v plug. Not for use on plastic tanks!
Am I missing something?
Don't all VW TDIs have plastic tanks?
The 2 golfs that I have had, both had plastic tanks.
Are there any models with metel tanks?
These kits don't look very useful for TDIs.
I don't see the filter heater sold separately.
That would be useful.
 

Jeffmx5

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Dunstable, MA, USA
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Since you asked....

MrErlo - here is the post I promised.

The data.

In my personal experience I have had my car fuel freeze up 3 times, all on B100 with Enerflow 100 additive. Each time I was able to start the car and drive off but the car died 1 mile down the road. The fuel filter was never the cause. On one occation I was able to determine the fuel line had a frozen, I believe at an elbow. I suspect the other two times were the same cause. I was able to verify the fuel in the tank would still flow out the sending unit in every case.

I have read of members here who have driven for 40 minutes and then their car died due to frozen fuel. In one case a member drilled out the check valve in the fuel sending unit while on the side of the road. He also observed crystalized fuel collecting at the fuel screen on the fuel sending unit. After drilling out the check valve he was able to restart the car and drive on.

With VAGCOM I have monitored fuel temperatures from a cold start. It took 7-8 minutes to get from -10C to 0C and over 40 minutes for the fuel temperature sensor to get to 35C.

I have also performed freezer tests on biodiesel and biodiesel with additives. When crystals form in fuel they sink to the bottom of the fuel.

Based on my experience and the recounted experience of others I have come to several conclusions.

1) Biodiesel must have sufficient additives that it remains mostly liquid in order to be able to start the motor. If too much of the fuel has crystalized the motor won't even start and it won't matter what heaters are where.

2) All restrictions between the fuel tank and the fuel filter must be eliminated. When the car is first started all the fuel is cold. Also since the car has been sitting for hours all of the crystalized fuel has precipitated to the bottom of the fuel tank, fuel filter, and the lowest point in the fuel line which is the 90 degree elbow near the fuel tank. Any restrictions will collect the crystalized fuel and form a clog that will quickly stall the motor before any heating can take place.

3) On an ALH motor the recirculating heat from the IP alone may not be enough to prevent fuel filter plugging. For example if the fuel is 50% crystalized then only half the fuel in the fuel filter can be used to run the motor. As that fuel is used the fuel coming from the tank is also 50% crystals. If the recirculation does not heat the filter up before it fills with crystals the filter will plug and the car will stall.

4) On an ALH motor the recirculation from the thermostatic T is not enough to heat the fuel tank. At cold temperatures it takes a long time for the fuel filter to get hot enough to open the themostatic T. Once it does the cold fuel coming from the tank will quickly cool the filter and cause the T to close again. The volume of the return line is small and the surface area is large. The fuel in the return line will quickly cool to ambient temperatures and crystalize like the fuel in the tank. If the fuel in the tank stays below the crystalization temperture for a long period, days or weeks, the crystalized fuel will build up in the bottom of the tank. Even if the fuel screen does not plug successive fillups of fuel will add to the layer of crystals and eventually the capacity of the tank will be filled with frozen fuel.

Based on these conclusions I think the following modifications will help.

1) Eliminate all restrictions between the sending unit and the tank. Drill out the check valves in the sending unit. Replace the fuel line between the sending unit and the fuel filter to eliminate the 90 degree elbows. I am not sure how to eliminate the 90 degree elbows at the fuel sending unit. Replacing the fuel filter with a Stanadyne style unit will replace the 90 degree elbows at the fuel filter. Using a larger inside diameter fuel line will also help reduce the restriction in the system. This way the slushy fuel has a higher probability to flow into the filter where it will be melted instead of clogging at the check valve or at an elbow.

2) Add a heater to the tank right in front of the fuel screen pickup. While I could remove the screen it also prevents large debris from getting stuck in the fuel line. It is possible to use some kind of engine coolant heater but I think this approach has several drawbacks. In my opinion it is much more difficult to plumb engine coolant back to the tank then to run wires. I think it will be more difficult to get the coolant lines through the tank. For electric wires the fuel sending unit could be modified so they pass through just as the fuel level sending wires do. If a lift pump is installed then it may be possible to tap the wires for the pump motor to add a heater. The coolant line will need to be bled which is already a challenge in these cars. If a failure (leak) happens it will disable the car. Finally an electrical heater will provide heat imediately instead of having to wait for the engine to get warm.

3) While this may be enough, since the fuel filter is being replaced anyway why not use one that has a built in heater. The two heaters can be wired to the same circuit. It should be live with ignition only. In addition the heaters should have internal thermo switches. When the fuel is warm enough the thermo switch opens and shuts off the heat. The heaters only need to heat the fuel above 0C. This will melt all crystals in the fuel. In the Spring, Summer, and Fall the fuel will always be above 0C and the heaters will never come on.

This is all just my theory, I have not put any of this into practice except drilling out the check valve.
 

cessna

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Iowa
TDI
2006 Jetta
I make my own biodiesel from resturant grease. Even when made properly it has worse cold weather properties than that made from virgin oil. Here is one way I deal with the cold weather problem. Store the BD in plastic 5 gallon buckets and let it freeze and solidify.I then take them inside the basement and put them on the workbench and warm. If you look at the bottom when the fuel clarifies you can see the white stuff causing the cold problems so I siphon off the top leaving the stuff on the bottom.You can probably use the bottom next summer if it clears up. If not you don't want it anyway.
Martin
 

MrErlo

Veteran Member
Joined
Apr 25, 2006
Location
Omaha, NE
TDI
2003 Golf 4dr 5sp
lift pump / tank heater

Jeffmx5 said:
If a lift pump is installed then it may be possible to tap the wires for the pump motor to add a heater.
i'm currently planning on installing a lift pump at the KC/Omaha GTG at the end of March. i'll start looking into wiring a heating unit as well.

thanks for the extended write-up, you seem to have given this quite a bit of thought. if i actually implament any of these heating systems, i'll make sure to let you know how well they work out for me.
 

RareAir_Biofuel

Active member
Joined
Jan 9, 2006
Location
Denver, CO
TDI
'03 Jetta Wagon
UPDATE:

Running B50-B60, car started up at ~0F after a night outside, no problem. Even had 2 bad glow plugs, replaced on a regular checkup the next week.

Car's running like a dream, I think the better flow of the new fuel line is playing into that just as much as the heater. Overall, stoked about the system. Of course, you can do up the primo kit people are talking about, but on a budget this kit is pretty damn nice.
 
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