Direct VS. Indirect Injected Engines and WVO - Blends

[LowGear]

Hi veggie,

No.  It wasn't a typo.  I found the information on a different site that was more explicit than the one I've listed.  And I was surprised too.

http://www.4btswaps.com/forum/showthread.php?7348-Isuzu-4BD1T-Introduction.  Four or five paragraphs down.

We've talked the RUG VS. PUG thing.  I couldn't find anything strongly against a splash here or there.

I've back stepped just a bit.  I've gotten hooked on processing the WVO way better than let it set around for a few months and then filtering off the to top few gallons off every few weeks down to 10 micron.  The few gallons I've burned seemed to have gone through just fine.  And the smell has greatly reduced.  Diesel here whether its straight or B20 like I buy which is still cheaper than PUG.

I sure hope nothing gets messed up.  Washing WVO too huh.

Casey

[WStayton]

veggie;

  You said:  "Has anyone made viscosity tester that they could share with us.?"

  Commercially available units to measure the viscosity of motor oil are, conceptually, just a leak against which the time to pass a certain volume of fluid is measured - the result if expressed in "centipoise" and I'll have to go look, in text book for a lubrication course, if you really want to know what the definition of "centipoise" is!  Yea, I know its 1/100'th of a poise for the comedians in the crowd, but as to the actual definition of a "poise" . . .

  I'm not sure about how the viscosity of fuels is measured, but it stands to reason that it must be something like the units for lube oil, albeit with a different orifice(sp?) for the leak.

  I would think that, if you were only interested in comparing one liquid to another, and didn't care what the absolute measurement was, you could just use some size "leak" against a quantity of oil and then measure the time for a certain volume to pass through it.
You would have to start in the same place each time, so that you had the same head pressure on the sample, induced by gravity, but then you could do a sample of fuel oil and compare it to a sample of mixed fuel and draw your own conclusions from that.

  Many folks who use WVO in a road engine think that it is important to heat the oil so that is of the same viscosity characteristics as diesel fuel in order to have proper atomization from/through the injection nozzles.  There have been some "studies" (word used advisedly) that proport to show that if WVO is warmed to the same viscosity as ambient temperature fuel oil, the spray pattern is made (more) nearly like that of fuel oil, while cold WVO lead to spray patterns that were really just dribble's or streams, not the nice cone shaped pattern of diesel fuel.  I should add that they above test were preformed with an injection nozzle suspended in a glass container so that the experimenter could see what is hapening.  What is actually happening in a combustion chamber, under compression ratios of 15:1 to 20:1, MAY be different, but nobody has fitted a running diesel engine with a quartz window so you could see the result - at least not that I am able to find!

  In short, are you sure that just thinning the fuel, even with RUG, without heating it, will give you a system that will work long term?  I should add, if you are thinning with RUG, then heating may not be a good thing since you might induce "vapor-lock" and there is the danger of fire to worry about . . .

Regardz,

Wayne Stayton

[Tom Reed]

I've heard of using a battery electrolyte hydrometer for fuel density.

[LowGear]

Diesel here whether its straight or B20 like I buy which is still cheaper than PUG.

Oops!

Diesel is consistently a half dollar more per gallon that Premium here and almost a full dollar more that RUG.  I've come to think RUG is better because it explodes easier.

Casey

[LowGear]

Viscosity checker:

How about a quart can with a small hole in the bottom.  Perhaps a a six penny nail.  Mark the container for 2 cups with another hole so that if you over it self levels to the same amount.  Time the draining of diesel, water, rug and then your Waste whatever.  Too simple?

Casey

[veggie]

A reservoir filled to the same level each time with different liquids, and timed until they empty.
Swappable orifices. I will start at .020" and see how the two liquids compare.
As Wayne stated above, the important thing is the comparison between the two fuels and does not need to reflect the API, Centistoke, or SSU viscosity testing standards.

I will share the results when completed.

Lets call it the VEGISCOSITY TESTER !!   

veggei

[veggie]

Hi Wayne,

Ref your comments:

"Many folks who use WVO in a road engine think that it is important to heat the oil so that is of the same viscosity characteristics as diesel fuel in order to have proper atomization from/through the injection nozzles."

Petro diesel at 104 f = 2.5 cS viscosity

Rapeseed oil at 180f = 10 cS

In order to get VO viscosity even close to Dino diesel it has to be VERY hot.

Rapeseed oil at 285f = 4.5 cS (which is considered close enough to diesel for comparable spray patterns).

How many veggie oil burners are heating there oil to 285f ??  Perhaps some.


"There have been some "studies" (word used advisedly) that proport to show that if WVO is warmed to the same viscosity as ambient temperature fuel oil, the spray pattern is made (more) nearly like that of fuel oil, while cold WVO lead to spray patterns that were really just dribble's or streams, not the nice cone shaped pattern of diesel fuel."

Agreed. Cold WVO (unblended, unthinned) would not atomize during injection.
However a blended fuel with the same (or close to) viscosity as DinoD should atomize much more readily.

Only two ways to use WVO.
1] Heat it
2] Thin it.

I'm totally in favor of both methods (heating and blending).
Each user will have their own reasons for choosing a WVO prepping method.

In my case, I have two reasons to try blending...
A] I have a couple of air cooled diesels that do not lend themselves to adding a water heated exchanger for fuel heating.

B] My opinion is that Biodiesel is the best alternate fuel (and requires no engine mods) however I want to try something simpler and safer (chemicals) than reacting biodiesel.

C] Rigging up dual fuel systems with heaters and fuel switching valves is not always feasible when you have several engines and vehicles.

Perhaps some of the "Blenders" in the membership could pipe in and tell about the things that worked (and did not work) for their engines ?

veggie

[LowGear]

Just so there is no confusion.

I have seen multiple Mercedes early 80's engines running mile after mile on straight WVO.  Some don't even warm it up.  Some haven't bought diesel in years.  It's warmer here.  I think some are crazy.  But it is going on.

Me.  I'm reading veggie, Tim and the others information pretty closely.  I'd be producing bio-diesel this month if I hadn't gotten strung out on purifying WVO with a centrifuge on my dryer.  I may say screw it and go forward and add the refinements as they become available on Ebay.

Casey

[Tim]

Casey,

I totally agree with veggie. But the thinnin part may be necessary for some engines or injection systems, but definite not all. Rudolf invented it for veggie oil, not that other stinkin' stuff .

I'm driving such a old Merc, blending only happens below 10 C (50F), from 5% to 50% when it starts freezing. I also changed the injectors to ones with a bit more reservoir at the needle, better quality ones and a bit higher injection pressure (+20bar). This is not theoretical balanced, but from my own experience and reading on the internet. I'm having them redone at the moment, so within two weeks can tell you more. Best achievements and results are done in winter, for that your have to wait till december .

The main problem, as written is mostly with bad quality oil, but also with a diesel engine with no load. When you use your genset at full pull, everything gets freakin' hot, which your engine loves, and the veggie oil too. Every sprayed drop out the nozzle will burn, burn like hell.

When you idle, half the drops wil burn, half will end up in your exhaust and engine. This will F it up in no time with veggie oil.

Tim

[veggie]

Casey,

That may be very true for the 80's IDI engines with single hole (larger hole) injectors.
I my case, I have 3 engines that are Direct Injection, so I want to experiment on which fuel is best for me.
Based on:
- Accessibility
- Ease of preparation
- Cost and type of engine modifications (if any)
- Fuel's ability for storage
- Safety

If running a DI engine on heated WVO turns out to be the better choice over blending (in my set of circumstances) , then I suppose I will go with heated WVO. I want to give the blending a fair trial first.

cheers,
veggie

[LowGear]

Aloha veggie and Tim,

My bio diesel guru in Seattle has a brother that has been blending WVO for years and putting it in his 90-something Mercedes.  He laughs at his brother, my guru, every time they see each other and hassles him about all the work and expense he goes through to make bio-diesel.  Oh, the guru runs a Mercedes, Dodge, motor home and heats his home with his bio diesel plant.  Credentials I respect.  There's just something about someone that says "This is what I've been doing for four years." that captures my complete attention. 

I think we'll all agree that bio diesel is a superior choice with the exception of costs.  I'm shopping Ebay daily for a cheap but adequate pump system to get my centrifuge up and cleaning.  If they won't ship Parcel Post I can't do business with them.  Paradise does have a couple of downsides.

Casey

[WStayton]

LowGear & Veggie:

  Commercial testers for oil don't go all they way to the end of the sample to measure the time because things get "funny" and depend on how many drops a minute you call the end, etc, etc,

  What a commercial unit does is start with a tall (maybe 30"?) column of oil, turn on the leak and then start the time when it gets down to some fixed level (say 24") and then stop the stop-watch when it gets down to something like 10", just so they don't have to deal with trying to figure out exactly when it quits running, i.e. when it gets to the bottom of the tube and has no pressure behind it.

  No reason you can't do the same thing with a piece of hose grafted in that is transparent, so you can see when it gets down to your cut off point, or just make your column out of hard plastic to begin with and scribe a couple of lines at say 3/4 and 1/4.  Just don't make it 6 inches long and try to measure from 100% to 0%, because you'll have too much going on at full to get a reading and it'll be hard to decide when the ending actually is.


Veggie:

  About the choice of words - it was a bad choice, and I knew, when I typed it, that heated veg-oil isn't of as low a viscosity as #2 Diesel - what I should have said was:  " . . . heat the oil so that it was/is more nearly the same as diesel fuel as they can get it . . ." 

  Thanx for catching it so that I didn't inadvertently/unintentionally mislead somebody and make them think that they could get the same viscosity out of veg-oil as #2 diesel simply by heating it to the limits of what hot-water-to-fuel heat exchangers can give us.

  I might add that a lot of the road crowd think that heating it to 180F is all they need to do . . . I don't think that is true - I think that the closer you get to #2 diesel viscosity, the less problems you will have, but even if you mix 35% (to pick a number) diesel and heat to 210F and the viscosity is the same as diesel, you will still have injector life and lube oil life  issues due to the non fuel "stuff" in WVO - even free has a price!  <grin>

  Of course if you are paying zero, or nearly zero for your fuel, you can afford to do more frequent oil changes and injector cleaning's and/or nozzle tip replacements.

  As Tim points out, increasing the injection pressure helps with old Mercedes but that has limits, because if you jack up the injection pressure too high, you will probably create issues with the injector unit which has to work harder to get those higher pressures - I'm increasing the ones that I will use in my OM616 for the reason that a little bit seems to help and, so far, as shown no bad effects.  But, geting 200 bar out of injector where 180 is specified (or 172 for some engines) is a lot different than thinking that if you just increase the IP to 350 bar everything will be fine, even if you do nothing else.

Tim:

  You say:   "When you idle, half the drops wil burn, half will end up in your exhaust and engine."

  I hope that you mean in cold ambient with no measures to prevent it.

  I think that if you increase the IP, preheat the fuel to as near 210F as you can get, and use a mixture of 25% to 35% # 2 diesel, and ONLY use the veg/#-2 blend after the engine is warmed up, you will nearly eliminate the problems associated with using WVO.
I am assuming, here, that you filter the WVO down to 1 micron before you blend it.  I feel that you will only then have the problems associated with having things other than veg oil in the fryer oil, such as dirty injectors earlier than with straight # 2 or having to do more frequent oil changes.

  If you don't believe this, what do you believe and why?  Enquiring minds, and ones like mine, want to know!  <grin>

  I should preface everything that I have said here by saying that it only applies expilicitly to older indirect-injection Mercedes engines -  I think that it pretty much applies to Listers and clones, but as to other engines, particularly direct injection one's, I have no knowledge or opinion . . . well, maybe I have a couple of opinions, but they aren't worth much!  <smile>


About making/using boidiesel instead of WVO:

  I think that bio-diesel is superior to WVO for use in any diesel engine.

  However, due to the Marcellus Shale gas stuff, we have EPA types swarming all over the place and I have read of them finding a few guys making home-brew bio-diesel where they shut them down, labeled their work area as a Hazardous area, called in a hazard team, in cute little white suits, to clean it all up and then billed the previous bio-diesel makers for the services of the hazardous waste guys AND also slapped them with a fine for polluting!

  Not wanting to wind up in the pokey, looking out through the bars, and to keep the EPA's hand out of my pocket, I have tried to stay away from the whole area/subject of bio-diesel, thinking that one set of clean-up fees and EPA fines would pay for a lot of injector cleanings and early oil changes.  I am hoping that if I stay under their radar, I minimize my chances of having a problem . . . Maybe that is true and maybe not - time will tell!!  <grin>

  Also, what do you do with the stuff other than fuel that results like, glycerin, etc., etc.  I am sure that they EPA would view that as a hazardous waste also - so there you go, off to the pokey, again!  <grin>

  On that note, I bid you adieu, at least for today!

Regardz,

Wayne Stayton