Hi

I had a thought on how to improve my vapour system.

I figured ( see pics on page 1 ) that having holes in the top of the can likely lets vapour out before its burnt.

So i figured maybe having a long air inlet tube attached to the side of the tin and have fuel in the bottom of the tin. You could also have a second tin connected tot he first tin by a tube, so that you could have a richer mixture of fuel in the air/fuel mix - this could be useful in colder climates where a richer mix is needed to start and run.

I might try and build this second version and post back.

Cheers

PS77

Hi spewing



Ok, my plon was to create a coffee tin vapouriser. I grabbed a coffee tin, punched a 32mm ( 1  1/4 inch ) daimeter hole in the tin lid, connected a pvc drain pipe which I got from a hardware store, leading from the tin lid direct to the carburettor air intake on the engine. I put the tin lid back on the tin.

I punched 8 half inch diamter holes in the lid to let in air so it combined with the fuel vapours.

I drained the carburettor of petrol.

I put petrol in the tin to depth of 1 inch roughly. ( I later replaced the petrol with 95% pure ethanol ( also known as methylated spirits ( or metho ) which I purchased from hardware shop/supermarket ).

I dropped fuel into the carby by the hole in the pvc pipe ( shown in one of the pics ) so the engine would start and once it kicked as long as the fuel vapours were available, it would run. There is no picture showing the drop pipe and I apologise for that. I also used a squirter bottle but its hard to get the air/fuel mix right to start it and then get the pvc pipe on quickly, so I reverted to using a dripper system through the hole. This dripper system isnt really important.

Does it work -   Yes it does, very well in fact.
Does the engine run up to full power - Yes, no problem.
Which burns cleaner? - Ethanol without a doubt. Petrol is actually quite dirty quite frankly.....
Is this system GEET? No - its a vapour maker and is an open system, where as GEET is a fuel cracking system that is in fact a closed system ( fuel/air recirculates ).

Does the system need a fuel heater? Yes it does - I didnt do much more than sitting the tin in a bucket of hot water ( not shown in pics ). I was amazed at how fast the tin got really cold because the fuel evaporates so quickly. In cold climates this would be a problem.

As the vapours are created, the fuel temperature drops quickly to the point where vapours cant be created and the engine stops. One solution is running a small coiled copper pipe through the fuel tin and use hot exhaust gasses tapped off the exhaust to heat the fuel by passing the exhaust gasses through the pipe ( dont put hot exhaust gases direct into the tin as you might get an explosion... OK I've now warned you.....).

Another solution is using an electric fuel heater as this would give better control of fuel temperature and fuel evaporation ( vapour creation ).
 

Possible Improvement ( or "Vapour System Mk II" ) :
======================================
(1) Put air inlet on side of tin to stop vapour loss to atmosphere
(2) Put fuel heater immersed in fuel ( or under tin bottom ) to keep fuel constant temp.


Further Possible Improvements ( or "Vapour System Mk III" ) :
=============================================
As above, but add second tin ( connected by same diameter pipe ) also with a fuel heater. Second tin outlet pipe connect to engine carby.
 
Air comes into first tin, mixes with vapopurs. As engine runs it creates suction and sucks fuel vapours from SECOND tin, but as second tin has vaopurs sucked out of it, this creates a vacuum and causes   vapours to be sucked in from first tin. Now we have a double system that shoul allow a richer air/fuel ratio which can be used for colder climates.
I havent built the Mk III yet, but am hoping to. It should, in theory, work fine.


Hope this helps explain things better.


Cheers,

PS77
 

Hi Didit,

Can you give me more info on what you mean by this please?

(1) "You kind of want to make a bubbler out of you vaporizer to produce the most vapor." 

(2) "I plan on having four air filters with copper lines drilled with several holes so the engine can just draw what it needs.  Hope this helps."

Cheers

PS77

Hi Didit,

Can you give me more info on what you mean by this please?

(1) "You kind of want to make a bubbler out of you vaporizer to produce the most vapor." 

(2) "I plan on having four air filters with copper lines drilled with several holes so the engine can just draw what it needs.  Hope this helps."

Cheers

PS77

Basically you want to draw your intake air through the gasoline and produce a bubbling effect.  Through your younger days or now you may have come across a Bong, LOL.  Sucking through the top of the bottle draws the air through pipe and into the water creating bubbles, same idea as the vaporizer.  The idea of all the copper lines and holes drilled through is essentially the same as the bong but instead of having just one "pipe" created the bubbles, the holes make up the same air volume but distributed through the entire vaporizer instead of one localized spot.

Hi Didit,


Ok, thanks for the info. I now understand the concept youre talking about.
Presumably the bubbling will add more air into the fuel and help it vapourise better?

Hi yaz,

Well the idea of an injection system is to add the fuel efficiently to the engine, which means burn it more efficiently. However, injection is not that efficient - a vapour system ( assuming it has no leaks ) is pretty much the most efficient way of adding fuel to an engine.
Injectuion systems add liquid fuel drops to an engine, where as vapours are a gas and are the highest level of fuel dispersal in air you can realistically get. If a vapour system gets say 50 MPG and an injected engine gets say 25 MPG, the vapour system is 100% more efficient than using injection.

Cheers,

PS77

H,mmm....if you pressurised fumes, they might turn back to liquid.....

Thank you Very much for your time indeed!

I can get an engine identical to yours, But it is like 11.5 HP, and i think its rated at round 330 CC. You have brought good stuff to this forum dude, and i appreciate that!

Thank you for sharing!~