Here in Denver ULSD is the only fuel available to blend with. I drive a 1996 F250 7.3L. I have been blending 50:50 UVO & ULSD. My UVO is cold upflow setteled, then heated and CF'ed. Very dry very clean. When driving 75mph my Fuel Filter light comes on, (high flow conditions). The engine does not hesitate or stall. If I switch to the 100% ULSD tank the filter light goes off after a few min.

I hesitate to add any fuel that has a higher potential head pressure than diesel, sic RUG. Should I decrease the % of VO costing me more, or what?

Another question is how far should I drive (city streets) to purge the blend before shutting down my truck?

Sounds normal, the thicker blend causes a higher pressure drop across the filter at higher flow rates. Could be a bad thing if the filter light is indicating low lift pump pressure to your injection pump input, depends on what makes the filter light come on, I don't know the details for your vehicle so hopefully others will know what controls the filter light. Reducing the amount of veg in the blend would likely keep the light from coming on. A friend here has the same problem with his 93 Ford 7.3L IDI pickup, the filter light flickers every now and then when the weather is cool, he ignores the light?

Mix with kerosene.

Right now I run 50/50 with heaters,diesel/wvo.Cool morning here.August will be back to 70/30.
I always blend in diesel that way I need no heated fuel pickup,and easier to pump fuel in car.

I'll second UFO's comment. Kerosene is great for blending. You can't let a little issue like road taxes stop you. It's a pain having to pump into a container then into the vehicle, but it really blends well and has better cold weather properties than ULSD.

Here in TN its over $3.00 a gal.

Ya, that's the only issue with K1. Here right now it's about the same as ULSD, but who know's how long that will last.

Drive less than 75 mph. Seriously, is the speed limit really 75 there?
Add about 5% K1 and compare, or lower your speed a little and compare.
Continue to learn the tolerance of your truck and decide on the trade off you are willing to accept.

I have run 100% vo for the last several months. I rarely drive above 60.

Yes the interstates I76, I70, & I25 are 75mph between urban areas. Eastern Co. is rolling high plains desert. I have to make a triangle trip from Denver to Hudson to Ft. Lupton and back every Mon. If I couldn't drive 75 for 45% of that trip, it would be all I could get done.

I'll try adding K1 to the blend.

No one has addressed my second question, how many blocks/miles should I drive 25-35mph to purge my fuel system so I minimize carbon build up?

quote:

how many blocks/miles should I drive 25-35mph to purge my fuel system so I minimize carbon build up?

What is the GPM of the fuel feed [lift] pump?
What is the volume of the fuel system downstream of the fuel switching valve?

Both good questions. I not sure the owner's manuel contains that info, I'll do some research.

Anyway I got a shock when I bought some K1 at a farmer's coop last week $7.00/USgal. Ouch!

Further searchinf found K1 @ $4.25/USgal. Boy blending with K1 kills any financial savings.

Instead of K1, use "Stove Oil" same stuff, much cheaper. Available from most bulk fuel dealers. It's the fuel for Monitor and Toyo heating stoves.

I run what i run 100%, no purge.
Purging is for two tank individuals who post under WVO/SVO.

**BUT**, if you take note---almost all blenders are also single tank WVO/SVO.

quote:

Originally posted by jdfoxinc:

No one has addressed my second question, how many blocks/miles should I drive 25-35mph to purge my fuel system so I minimize carbon build up?

That Ford 7.3 powerstroke has a return line from the fuel rail so just letting it idle for say 5 min should purge the system. Newer versions didn't return but I'm not sure of the cut off year for that update

quote:

Originally posted by jdfoxinc:
found K1 @ $4.25/USgal. Boy blending with K1 kills any financial savings.

I buy pump diesel in a 150 gal. tank in the winter and save for year round. Its just as thin as K1 in the Denver area, I have run viscosity tests on it.

quote:

I buy pump diesel... in the winter and save for year round.

I do the same. Simple, easy, and I pay the motor fuel tax. I don't believe in cheating on taxes.

Pump diesel? Is this the same as off road, and who carries it?

My understanding is that winter blend pump diesel is essentially regular diesel with kerosene added to prevent gelling and aid cold weather starting. I bought 100 gallons when prices dropped in the late winter and only recently ran out. I plan to buy several hundred gallons this year.

quote:

winter blend pump diesel is essentially regular diesel with kerosene added

Perhaps in some regions. That wouldn't work where it gets below freezing in the winter. The wax component which causes gelling has to be removed, not diluted. It's similar to PHO/fats in biodiesel.
Refineries vary the output from the processing units to provide fuel which is seasonally adjusted for the temperature anticipated. This might help in understanding how a refinery works:
http://www.chevron.ca/operatio...fining/treatment.asp

quote:

Originally posted by jdfoxinc:
Pump diesel? Is this the same as off road, and who carries it?

At all stations thats the only kind they sell during the winter months, buy some diesel from any station in Denver during Jan-Feb. its the thinnest you can get, as thin as 100% K1. Not off-road, that simply has no road tax paid.