Fuel Vapour System - Got it working!!

[crashhh]

Deja Vue!  I built virtually the same thing in 1981, including the pipes. 
Only difference was that I built a perspex box with a float at one end to keep the fuel level constant instead of the can.  I attached it to the air intake of the carburetor of an old Datsun 1000 station wagon, and it worked.
A few problems I encountered were as follows.
First, additives will be left behind in the liquid fuel as they don't evaporate at the same rate.  In my case the Datsun required leaded fuel, which was being left within the liquid.  It pinked it's brains out when accelerating.
Secondly, the evaporation also carries away thermal energy from the liquid, and so it cools very rapidly.  As the evaporation rate is affected to a very large extent by the temperature the engine will quickly lean out if that heat is not replenished constantly.
It's quite important to keep the liquid at a constant temperature or your fuel usage will vary markedly between a rich mixture, and one that won't sustain combustion.
I don't know whether to congratulate you or not.  If I do, then I am also effectively patting myself on the back as well.
I did race off to the patent office, and discovered that Chrysler already had an evaporator patented, and so did Honda, though they were both quite different to this in how they worked.  The Honda one was quite interesting.  It was a circular chamber sort of like a snail shell, with the head end below a carburetor and the spiral finishing at the inlet port.
All the best!
Vince

[ashtweth_nihilisti]

At Plasma Student. Got this From Naresh (the GEET guys) for you

it kind of looks like only the lighter fractions are getting evaporated?.
Is there exhaust heat used to evaporate all fractions of the petrol
together evenly?Is there an exhaust pipe inside the big PVC pipe?

[plasmastudent77]

Hi All,

Thanks for the feedback - much appreciated!

OK - I tried some other fuels in my "coffee tin vapour maker" and this is what happened:

(1) Fuel was 95% ethanol ( methylated spirits bought at local supermarket ) - ran fine. Runs up to full power and runs smoother and QUIETER than petrol and exhaust smells very clean by comparison to petrol. Power sounded a little down ( I dont have a dyno to test properly ) but you would expect that as alcohol has less calorific value per kg than petrol. Would be a suitable fuel if needed.


(2) Added water to 95% ethanol fuel alcohol, so the fuel mix was 40% water, 60 % alcohol. Ran OK, but a little inconsistent and had to ease the throttle open gradually to stop misfires ( due to water vapour I think ). Ethanol absorbs water, so water and alcohol are a good to use together. This misfiring might improve when I pre-heat the fuel. I'll let you know.....

I also noted I needed more air with ethanol than when running on petrol, so that the air-fuel ratio needs to be higher. I opened up the feed pipe so more air went in and the combsution settled down and was more stable. I'll test this some more and report back.


An important point here - this is NOT GEET. It is a fuel vapour system. It is really a 1/2 GEET system if you want to call it that as it is using only 1/2 the setup. GEET uses fully recycled exhaust vapours going into the fuel tank to go "closed loop". I am not doing this - I am using fuel vapour evaporation to produce fumes and is "open loop".

The next step will be putting the fuel tin in a bucket of hot water so the fuel is preheated to produce fuel vapour more consitently. As the fuel cools down, even through it turning to vapour, the tin gets colder and colder and so vapour production slows down and slows down so that the engine eventually stops.  A fuel heater ( the bucket of hot water ) is safe and will allow me to test over a longer period. If this system was on a car, I would expect the exhaust gas or radiator water be used to pre-heat the fuel.

Cheers,

PS77

[Chris31]

@plasmastudent77

Did you get to test right down to empty fuel tank?

The fuel evaporates quicker than water, so the engine is using the fuel and then leaving the water behind.

I have not built a GEET Im wondering if this same thing happens to GEET? proper fuel are consumed but water and junk mostly stays behind...

This is probably why the mixture get leaner and leaner as the engine consume the fuel...if that make sense 

[plasmastudent77]

Hi

I havent run it down to empty as I've only really started doing this, however what you say makes sense.
My thinking is that if the fuel is clean ( eg alcohol+water  ) then over a period of time after say a few tanks of fuel, maybe the engine would be cleaned up and the exhaust would run clean enough to produce very little gunk. I suspect after a period of time the fuel tank would have to be emptied, however the fuel+water emulsion would have to result in some of the water being consumed at least, if only as steam.

One thing that does stick out is that even fuels thought generally unusable ( I havent tried diesel yet - next on the list ) might be usable. I think though that the GEET process of recycling the exhaust into
the fuel tank to aerate the fuel and make sure the different fuels are mixed up properly ( mixing I think is important ) then all of a sudden you expand the capabilities of an engine. With vapour or GEET
you might also be able to mix say a small ammount of alcohol ( acting as a solvent and producing highly combustible fumes to get combustion going ) and vegetable oil  ( the fuel ) and produce an overall usable fuel. I think this is a good step forward.

I also think its possible tio use say HHO as a starter fuel, or even as a necessary additive to allow the combustion of say heavy vegetable oil ( better suited to diesel usage ) in an engine that normally uses petrol.

All this is to be explored yet, but I think the possibilities are intersting. If oil went up drastically again in price, or we had a serious war that dried up most fuels ( highly likely ), this technology would allow folks to be able to at least move around, rather being held "hostage" at home by high fuel prices or non existant normal fuel supplies.

I think older carburetor engines and diesels are better suited to this type scenario, but fuel injected engines could be used but need to have the injectors disabled and turned into vapour systems or crude carburetors fitted to them - which isnt hard to do. I used PVC pipe and a coffee tin to prove how easy it is.

Food for thought.....I'll update this thread as tests continue.

Cheers

PS77