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General Information => General => Topic started by: ORCoaster on March 07, 2012, 07:38:53 pm

Title: Viscosity Difference in Diesel?
Post by: ORCoaster on March 07, 2012, 07:38:53 pm
Can anyone tell me if ULSD is thinner than diesel made from waste oil?  I picked up a tank of Bio D  99.9% and it cranked about 5-8 lbs more on the IP gauge I have in the car.  It may have been the cold but the car is more advanced at that RPM going 65 and I was wondering if I ran it all the time would I have to reset the initial setting from 92 mm to something more around the 88 mm called for on the label in the engine compartment?

The things I think about when the drive is boring. 
Title: Re: Viscosity Difference in Diesel?
Post by: 8v-of-fury on March 07, 2012, 08:16:55 pm
Your brain is magnificent. Did you know that? I am scared to see your dash board.. 17 gauges, to monitor EVERYTHING lol.

Interesting, Did it sound clackier?
Title: Re: Viscosity Difference in Diesel?
Post by: ORCoaster on March 07, 2012, 08:49:42 pm
Well, at least I have one fan.  My wife thinks I should think less and do more.  Yeah, I like to know what is going on with the parts and pieces.  When I finally get to monitoring the temperature of the wheel bearings I might have enough pods and overhead displays that I won't have to watch all the silly drivers out there. 

So do you know if it is thicker than ULSD? 

I wouldn't say it was any smoother because I stopped, filled and then proceeded to merge back on the I way.  So radio was cranked, engine humming about normal and I was thinking about the cause and effect of the fuel.  I will try to notice as I drive in town over the weekend.  That is where I notice I have the most click and clack going about 27 mph. 

Will report on that later. 

By the way, in the gasser pickup (yes, a Ford Ranger 4x4) I use one of those ScanGauges, there is some serious distraction there for information.  Right off the ECU. 
Title: Re: Viscosity Difference in Diesel?
Post by: Baron VonZeppelin on March 07, 2012, 09:15:03 pm
Idunno their viscosities right off, but it would seem like bio would be thicker. Make your own zahn viscosity cup and time them both.

It wouldn't be industry standard specs, but would give a measurable answer.

Plastic cup - drill a hole - mark a reference fill line - finger over hole - fill to line - time with stop watch until draining bead breaks.
Title: Re: Viscosity Difference in Diesel?
Post by: ORCoaster on March 07, 2012, 09:18:31 pm
Will do this weekend as I am in the apartment and mom won't know what I am doing with diesel in the kitchen sink. 
Thks Baron VonZ.

Does cup have to be flat across the bottom or would a cone or depressed bottom be better?

Taking me back to my Research Assistant days you are. 
Title: Re: Viscosity Difference in Diesel?
Post by: CRSMP5 on March 07, 2012, 09:56:54 pm
yes bio is thicker then diesel...

another thing i found running bio... the breather system will also seep more oil then when on diesel..
Title: Re: Viscosity Difference in Diesel?
Post by: Baron VonZeppelin on March 07, 2012, 10:08:22 pm
Cone concave depressed bottom would be best.

But even flat bottom would work for a side by side comparison.
Title: Re: Viscosity Difference in Diesel?
Post by: 745 turbogreasel on March 07, 2012, 10:37:59 pm
Pretty sure ULSD is thinner than piss.

Wheel bearings...you should get an IR pyrometer, they are awesome.
I used to check catalytic converters by gauging the sizling of my hand...no more!
Title: Re: Viscosity Difference in Diesel?
Post by: R.O.R-2.0 on March 08, 2012, 07:21:04 am
yes bio is thicker then diesel...

another thing i found running bio... the breather system will also seep more oil then when on diesel..

i thought it was imagining things.. but YES.. my breather definitely drips more with bio-d
Title: Re: Viscosity Difference in Diesel?
Post by: CRSMP5 on March 08, 2012, 07:54:11 am
now why does it.. :D i gots a theory.. and it goes with the thicker fuel.... and IMO bio runs better then diesel... so why would breather seep more..
Title: Re: Viscosity Difference in Diesel?
Post by: ORCoaster on March 08, 2012, 06:35:56 pm
Here's my theory to theory.  The Bio-D is thicker thus it will act more like old sulfur laden diesel of old.  Which is a good thing.  Now once it gets into the cylinder it acts different.  Someplace I looked at the additives that you can add to ULSD to make it slicker.  WVO was super high on the list for being slick and I think Bio-D retains some of those qualities. 

So think of a slime buildup on the cylinders and what do you get?  Better sealing.  But it comes at a slight cost.  Scraping off and out the bottom and into the vent lines.  Blowby? 

I did notice that after an hour and a half on the road I pulled off to drop some wood at my sons house.  Getting back on the I-way I rapped it up in third and was blowing blue smoke out the back much more than I do with regular D.  If I put my water catch back on the vent hose I bet I would see more capture than I used to get.