E85Forum.com

novaz · Joined: 05 Nov 2009 Posts: 3 Location: Seattle

Just finished testing some E85 and was surprised to see it at
test #1 =86.42
test #2 =84.48
I realise that both of these are good results Very Happy

my query is for it to change 2points with in 1/2 hour from the same batch is that normal I am filling 5 gallon plastic race cans from the same source that was testing at 81-82around xmas.
second question is why is distilled wated preferred is it because of metal particles affecting the%
Roy

Alcohol · Joined: 17 Apr 2007 Posts: 471 Location: Central Wisconsin

Roy - I strongly suspect that this was only the variability of the test itself. The alcohol test using the water method is from my experience accurate +2 to -2 when done carefully. If you were using the Kent Moore tester then time/air exposure is absolutely critical- I have seen car dealer shops blow the accuracy by 10 to even 15 % if they did not follow procedures perfectly.
I find our state test lab using VERY expensive equip off by 2-5% due to the fact they have to do a dilution method. The only truly accurate test that is simple and repeatable is in a lab using the Karl Fischer analysis method.

The first method, done well, is plenty accurate for normal high performance applications. Just do not expect perfection in the test itself because water temp, fuel temp, sample size, sample collection, and measurements are critical to even stay within the above tolerance.

Distilled water would be best due to possible secondary bonds to the hydrocarbons- if the bond is strong enough it might not be enough for the last % to release and go with the water- at least that would be my theory.
I do not generally bother with using distilled however because I have the lab for quality control and only use the water test in the field as a quick analysis.

novaz · Joined: 05 Nov 2009 Posts: 3 Location: Seattle

Thank you
I was really carefull about my test equipment in cleaning and drying
its a good sign that my results were within what maybe expected
appreciate your reply Very Happy

Alcohol · Joined: 17 Apr 2007 Posts: 471 Location: Central Wisconsin

Correction- I must have been asleep on my last post;

The Karl Fischer test is for water only-- I knew better because this is the test we have going around the clock in our lab. Rolling Eyes

440Jim · Joined: 01 Jan 2008 Posts: 152 Location: Maryland

I do the water test on the batches I buy.
If you are careful, 1-2 percent error is in line. It is easy to be off by 3-4 percent.
I use distilled water to try and eliminate variables.

How much water/E85 did you mix? ie 100 ml total
What is the graduation on the container you use? ie 1 ml, 0.5 ml, 0.1 ml

_________________
'69 Dodge Dart 511 CID 3215 lb Ron's Injection http://www.ronsfuel.com
E85: 1.23, 5.79@116, 9.21@142 mineshaft air
E85: 1.26, 5.88@115, 9.33@141 summer air
Methanol: 1.25, 5.76@118, 9.12@145, -650' DA