Bio Diesel Cold Test.

[SHobbs]

Headshot,



No intention of starting anything here, but when I switched to B100 I gained a little in mpg. I only gained around 1mpg and I have checked the mileage three times. Advancing the timing from what I understand is to help deal with the increase in NOx emissions from blended bio.

 

[Headshot zod]

Thats fine, its how we learn around here.



This is how I thought it went down. Cummins retarded the timing to decrease NOX. Thats why advancing it is a cheap performance trick. Increasing the timing makes for better combustion and therefore greater heat, ergo greater NOX. B100 has a higher oxygen content and therefore burns better and increasing NOX. So advancing the timing and using B100 really increases NOX. Also I thought advancing the timing allows you to take advantage of the better burning fuel.



Any ideas on this? (it might be offtopic at this point we may need to start a new post)



Of the engines using B100 the 5. 9 has the lowest increase in NOX then VW and Benz. I'm thinking because the VW and the benz have such higher compression ratios then we do. I caught this factoid on a Biodiesel video.



Introducing a small % of hydrogen gas to your intake will eliminate most of your NOX.

 

[Josparkz]

How high a compression ratio are we talking about there?

Of the engines using B100 the 5. 9 has the lowest increase in NOX then VW and Benz. I'm thinking because the VW and the benz have such higher compression ratios then we do.

 

[Headshot zod]

cummins around 16 or 17:1 and mercedes around 22:1

 

[Josparkz]

cummins around 16 or 17:1 and mercedes around 22:1

Why so much higher on the Benz?

 

[Eco Rednek]

Really COLD!

Still running the B100/B20/K1 mixture,



Last night we had some near record cold temps... At 10pm it was -1F in Boulder,

drove up the canyon to 8300' and it was -7... over night lows were probably around -15.



I have a jar of this blend after having just changed my fuel filter... ... It sleeps out on the porch. This morning it had reached it s cloud point, and I did not try starting the truck. Came back at 11: am and she fired right up, temps still below 0.....



I am pretty impressed with how far a little K1 goes in the cold, all in all, I am still running like 70% b100.



Been plugging the truck in too, what a huge difference, starts up like it s been running all day.



Also, having changed the FF the fuel guage seems to be moving alot more slowly.

 

[Msilbernagel]

Why so much higher on the Benz?

Might have to ask the designers about their goals - but in general, higher boost means higher effective compression ratio and therefore the static compression ratio (of the pistons) is reduced to accomodate. Having a turbo is pretty much the same as jumping up and down to squish the contents before closing the lid. . non turbo'd engines just up the CR to try and get similar gains before going too high.



I doubt a 'normal' 300TD Mercedes runs anywhere near the boost we see on the Cummins, but that's just a guess.



With no turbo at all, you'd expect to see the higher CRs used by designers.



This is also why you see lower compression ratios on the turbo'd gas models - same issue. At some point, either effective CR of turbo/low static CR, or with high static CR and no turbo - the stuff get's squished enough to detonate and the engine self-destructs.



I don't know what happens with a diesel when the effective CR is too high, it may simply be a mechanical (stress) problem. Or. . the injectors can't push the fuel in, or the valves leak, or... ?



Mark

 

[DFerverda]

DLGonzo

Did ya figure out why you were jelling.

Are you making your bd or buying it??

I found my trouble, I bought my diesel fuel and a gallon jug full to test my bd with.

I was jellin all over the place, than i put straight diesel in the freezer and it turned to goo real quick, they did not put in any antijell,,, in december..... I bought from a new source and now my bd mix at 50% is clear and great at -2°f.

got 50%mix in truck now no trouble.

Dirk

 

[DLGonzo]

Dirk,



As far as the gelling. With strait BD I extect it to thicken in the freezer. I make my own and the oil I use is partially hydrogenated, so again I expect it to gel under cold conditions. I'm running about a 20% mixture with normal Petrol Diesel right now with no problems. I think I may not have dried my first two batches quite enough after washing either. I got a little impatient. I have since constructed a drying tank with water heater element and air bubble. Kentucky winters aren't too bad, but never the less I'm ready for warm weather again.



Doug

 

[DFerverda]

Doug

Check this out just use your glyc from the last batch.

http://biodiesel.infopop.cc/groupee/forums/a/tpc/f/419605551/m/9441081511

Doing this will use up a couple gallons of wvo but you can vac it off the top after it settles out, If you do it for the winter months you wont have to worry quite as much.

Also try the glyc pre wash, just add 5% water after the reaction and let it circulate for 15 minutes, and than shut down and let it settle as usual, It makes it a lot easier to wash.

Dirk