Author Topic: Stale gasoline  (Read 509 times)

Jhanananda

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Stale gasoline
« on: October 30, 2016, 05:12:36 PM »
A month ago I started work of my deuce and half to get it back running again.  I had noticed in my trouble shooting that there was no flow of fuel in the return line, so I reasoned the return line wass probably plugged with grease. 

Anyway. I opened the fuel cap and found that the cap was just resting on the opening of the tank, which is not how I would leave it.  I also noticed that there was 3/4 of tank, when I had left it with only 1/4.  When I had left it with almost pure diesel fuel, so it was clear to light blue in color, now it was amber colored. 

So, I pumped out and drained the tank and got 42 gallons (128L) out of it, and it smelled like stale gasoline.  So, I concluded that someone had used my deuce fuel tank for a waste bin.

I flushed out the tank with 5 gallons of clean diesel fuel, and got about 2L of dirt, gravel, sand and silt out of it.

I tested the fuel with o-rings and found that BUNA-n and silicon seals swelled badly, so I was sure that it was not my fuel in the tank.

With some blending experiments I found that the stale gasoline had to be diluted in about 90% WVO before the blend would not swell seals.  So it is going to take about 420 gallons of WVO to use up this stale gasoline. 

So, while stale gasoline is a popular blending agent it appears that the alcohol that is blended in USA gasoline does not evaporate as fast as the light fractions in the gasoline.  So, be careful when blending with stale gasoline (petrol).
I have run various blends of waste oils and unleaded gasoline since Feb, 2007 in a 1983 Chevy G-20 van with a 6.2L diesel V-8 engine, with a Stanadyne Rotary DB2 IP. I have started the engine with no difficulty on an 80/20 (WVO/gas) blend down to 3F (-16c).  I now run 60/20/20 (WVO/diesel/gas)

Jhanananda

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Re: Stale gasoline
« Reply #1 on: March 28, 2017, 09:50:14 AM »
I recently started to reduce the WVO content in my diesel fuel blends.  Two years ago I lowered the blend from 80% WVO to 60% in an effort to reduce injector coking.  I ran the same injectors for 2 years, and pulled them last summer, just to inspect them.  Only 4 of the 8 had any coke at all, and it was not much.  So, I plan to reduce the WVO content in my diesel fuel blends to 50% to see if injector coking, and ring and valve gumming, stop altogether, or it just delays the inevitable.  This also gives me a way to git rid of the Stale gasoline, by adding it at 10% to every blend from now on.
I have run various blends of waste oils and unleaded gasoline since Feb, 2007 in a 1983 Chevy G-20 van with a 6.2L diesel V-8 engine, with a Stanadyne Rotary DB2 IP. I have started the engine with no difficulty on an 80/20 (WVO/gas) blend down to 3F (-16c).  I now run 60/20/20 (WVO/diesel/gas)