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Basshopper
07-09-2005, 20:51
Does anyone know if fuel temp, flow and volume can be read with a scan tool? If not, is the Stand electronic pump effected by fuel temp or the optical sensor effected by fuel temp? Runs great up to 75mph then starts to miss.Does not do it on Diesel.

GMC Hauler
07-09-2005, 21:30
Fuel temp can be read on a scantool. It has to be an tool designed to read it, such as Carcode, Autoenginuity, or the Tech II.

I don't know if it would read flow in the way you are thinking, but you could look at fuel rate for the amount of fuel the injection pump is putting in the cylinders.

Do you have a gage so you could look at lift pump pressure while driving? That would be the first place i'd look. Maybe you're being starved for fuel at higher loads.

Basshopper
07-10-2005, 16:03
Here is a link to posted results and know I am at a stand still, Have pressure but not enough volume but other people seem to have it working with same fuel line. Your thoughts

http://www.greasecar.com/forum_topicview.cfm?frmtopicID=2752

GMC Hauler
07-10-2005, 18:58
Where are you measuting pressure? (I would assume from the fuel manager drain). Is your filter new and not clogged?

Basshopper
07-10-2005, 19:45
the Gauge is inline just before the Injection pump and after both filters. So that I can switch back and forth from Diesel and VO. The 2 systems are isolated the Diesel filter and VO filter are seperate.

GMC Hauler
07-10-2005, 20:57
Read your post on the Greasel page. It seems that the injetction pump is not getting the required fuel. These diesels are known to studder or stumble a bit if the lift pump is now working good (not enough pressure/fuel at the injection pump).

I'm assuming that the WVO is thicker than diesel. You could try cutting the WVO with diesel and see if that fixes the problem. I would mix your WVO tank 50/50 WVO and diesel, and see if this makes it better or not. If it gets better, than your line is too small/not enough pressure from the lift pump. By doing this, you would eliminate your WVO systems from causing the problem. You could also run straight diesel in the WVO tank.

Try both. That would give you good data. If absolutely no problems with the diesel fuel in the WVO tank, then you know the one variable causing the problem.

Basshopper
07-11-2005, 12:00
thats a great idea, When the VO gets down towards the bottom I will put in 10 gallons of Diesel and test it. That will give me about a 50 50 mix. I would be hesitant to run straight Diesel in a heated tank. Will let you know the results.

Basshopper
07-14-2005, 13:28
I did a mix of 10 gal D and 40 gal of VO since that is how much I had left in my tank. I ran it up to 95mph without one studder.The VO temp was 170deg. So does the mixure thing it to flow better through the fuel line and filter? or what would your take on this be. I have heard of some guys mixing 1 gal of Kerosene with 50 gal of VO would accomplish the same thing. Thoughts????

GMC Hauler
07-14-2005, 18:19
Sounds like running VO straight is too thick. Mixing other fuel to thin the mix would work. If you are wanting to run straight VO in that tank, then your next step would be to run a larger temporary line and a very good pump to the IP (filtered, of course). You could use some rubber fuel line. I would use the rubber line temporarly until you verified it was a fuel delivery problem. If it works with larger line and higher pressure, then you know where to go from there.

Remember, your fuel needs to be warm, but the PCM will go into some kind of limp mode or reduced power mode if the fuel is too hot. I dont remember where that happens. Anyone here know?

DChristie
07-15-2005, 15:57
Greetings!

I'd urge caution on mixing VO and Diesel because the mix isn't stable. (it will seperate like milk and cream) And the mix has issues with coking injectors.

At 160 degrees the kinematic viscosity (in centistrokes) of the VO is close enough to diesel to flow through our engines. It's below 20 centistrokes (mm2/second) at 175 the viscosity drops below 10 centistrokes which will allow it to be used in any diesel engine.

I had issue with recycled VO in my truck and the optical encoder. The darker color of the oil caused the sensor to not "see" the wheel. Causing a stumble shudder miss whatever you want to call it. Solution: Filter filter filter or swap to a mechanical IP. :D I use a set of filters; the first is a spin-on oil filter that catches down to 25 micron, then a spin-on Hydraulic that gets down to 10 micron, and finally a homemade 1 micron, to keep pressure and volume up I overheat the oil and let it cool a bit on the way to the IP. and use two lift pumps on the VO side, one pushing one pulling through all the filtration. :cool:

If you haven't done it yet, relocate your FSD. The added heat from the VO will fry it. (no pun intended) :rolleyes:

Sorry about the post length redface.gif
DChristie

Basshopper
07-17-2005, 06:49
What kind of pumps do you use,are both the same? So you push and pull the fuel at the same time is that what you are saying? What size is your feed line from the tank? and is it heated along the way such as a HIH?

thanks

DChristie
07-17-2005, 11:03
I run two Purolator Proformance #12s's one after the "rock-catcher" 25 micron and one again after the one micron The rock-catcher is gravity fed. 1/2" steel pipe 10" below the tank straight down.
The rockcatcher has a "hotsock" I made (coiled copper)to keep VO thin enough to flow through it, lard was a plugging concern until I did that.
I coiled 25' of 1/2" copper tubing (10" diameter coil) inside my tank which heats the entire volume of oil. I used 3/8" copper tubing for fuel line, yes HIH almost the entire length.
My first experiences weren't so great. I cooked my IP because of an undiagnosed coolant leak that removed about 1/3 of the coolant from my radiator. Then... In the summer here in Houston the truck would climb to 210ish and stay there if I wasn't moving. In Houston traffic, I sat alot. I figured it was normal for the truck.
I Found the problem when I fried my IP. :eek: :mad: :(
Silly me, I was stuck in traffic one day and figgered if I was going to have to sit there I'd do it for free.... Reallly hot VO. :(
I fixed the hole and now I rarely see 200 even for a pre '97 cooling system.

Not sure at first that I'd be able to heat all 60 gallons in my tank to 160 degrees, I routed the coolant from the heater out on the water-neck to the fuel line then the tank , then back to the heater core. I never could get the cab even "warm" in the "frigid" Houston winters. Ya know it freezes down here for hours at a time? tongue.gif
I fixed that error fast, I grew up in Montana but I've lived in the tropics; Houston, Hawaii, and Guam for the last 10 years. YEAh that's right, pity me! :D

Like I wrote earlier it put me off of fried foods for about a year.
Tip for you: restaurants don't own (for the most part)the grease trap, its leased as part of removal service, so look official, white hardhat, pocket protector, clipboard etc. and fill up any where you like. If anyone questions you, smile and say "just a little routine testing, we'll notify you if there is a problem. No news is good news."
Be tidy about it, they get antsy if you're makin' a bigger mess than the pimply faced kid that usually cleans out the grease.
If the oil is blond, use it, if it's dark, or black move on. doughnut lard is some of the best around. but you have to get it while it's hot. My tank gets hot enough I can liquify lard for use. :cool:

Oh yeah...the Hi-speed miss you are suffering maybe a supply/demand thing too, ie an under-rated aftermarket lift pump.

The only time I burn VO anymore is long trips, it's too problematic to use for local use. start-up and shut-down switching etc.

I hope this helps and encourages you smile.gif

DChristie