Q16 fuel

[wrench459]

We've been running the fuel in three different cars for a little over a month.
Two cars love the fuel But oh the third hates it.
Yes the jetting/fuel mixture was corrected.
Called VP and they said you must drain and flush all components after a weekend of racing.
This is due to the high evaporation rate and high lead content. Seems that that fuel leaves a coating on the carb. float pivots and they stick.
So far the fix is to drain/flush the fuel tank and lines. Then drain the carb and spray the floats with wd-40. OK no problem so far.
Has anyone come across the fuel breaking down the fuel lines?
This has turned into a mystery.. you touch the steel braided return line and it starts seeping fuel

[traytodd]

Q16 Fuel Properties Typical Test Methods
Specific Gravity @ 60F° .716 ASTM D 4052
Motor Octane 116 ASTM D 2700-86
Research Octane 120+
Reid Vapor Pressure 6.76 ASTM D 323 (in psi)
Distillation F° ISO 33405
10% Evap. 141.0 (Temperature (°F) at which 10% is vaporized)
50% Evap. 174.0
90% Evap. 214.5
E.P. 260.2 (End Point, Temperature at which entire sample is vaproized)
Oxygenated Yes
Leaded Yes ASTM D 3237
Color Yellow


The MON rating of 116 is extremely high as is the RON value. Straight benzene and xylenes are about 116 RON. The high knock numbers could be coming from the lead content. The fuel has high oxygen content implying it is either an ether or an alcohol. More likely an ether such as Methyl Tertiay Butyl Ether (MTBE), Ethyl TBE, or Tertiary Amyl Methyl Ether (TAME). Both ethers and alcohols can attack rubber with ethers probably the more aggressive. I am not sure if the yellow is a dye or a natural color of the fuel. If it is natural, that would imply a large amount of heavy aromatics (benzene ring compounds with long side chains, probably branched side chains to keep the octane ratings up). If illuminated with a blue, green or black (UV) light does the fuel strongly flouresce (ii.e., emit yellow or red light)? This would be an indication of aromatics.

The high evap rate is indicative of ethers and alchols. The residue is more indicative of heavy molecules such as the suggested aromatics. I would need to run a near infrared spectral scan of the fuel to tell you more exactly what its characteristics are but these are my best guessing looking at the available information.

Terry

[wrench459]

Thanks Terry for your reply.
I'll get a sample and place it under a UV light and see what happens.
I assumed the fuel was dyed so its now a step by step process to find out whats going on. VP said they've have not had any reports with fuel line problems.
Funny thing is all three cars are running Earl's lines with only one having problems.

[traytodd]

If you hold up the fuel in a clear bottle in sun light and it has a funny yellow/green appearance, that is fluorescence. If it just looks piss or straw yellow, then it probably is dye.
I have been doing some thinking on how I might design a fuel with these properties. There is a process in the refinery that is called a catalytic reformer. Its output after the light ends have been stripped out is called reformate (~104+ RON). (in the old Texaco ads they called it platformate which refers to the UOP platinum reformulation process). The reformer takes low octane light hydrocarbons and turns them into high octane ring compunds such as benzene, toluene, xylene and higher aromatics plus cyclohexane and other branched paraffins. Ring compounds and branched paraffins have high octane. Today, nearly all of the benzene and a lot of the toluene are removed from the reformate in the benzene stripper before it is blended into gasoline. This is done to meet EPA requirments.
To make a high octane fuel such as what is described, I would start with straight reformate before the benzene is stripped. Then I would add a high octane ether such as MTBE or ETBE. Finally, since this is not a street legal fuel, I would add as much tetraethyl lead as I could to further increase the octane rating. That is where I would start. There might be other compounds you could add to enhance it.

Terry

[wrench459]

Things are starting to heat up around here. The new season is just around the corner.
Pulled the problem child apart just to check.
Man did that Q16 fuel leave a heavy layer of gummy(lead)stuff everywhere.
The pistons also showed signs of detonation. Not good
There's got to be a better way..take this as a question,statement, or whatever.

So with our limited amount of experience with Q16. It seems to work good with a F/I systems. But put a carb into the mix....