# Alternative model engine fuel.



## oneKone (Aug 11, 2015)

Hi,
I figured out I'm allergic to pump fuel and methanol so I'm going to have to drop them as a fuel for model engines. 

I was wondering if anyone knows of any systems where LPG or butane can be used as a fuel without leaking everywhere. 

Cheers,
Chris


----------



## Jasonb (Aug 12, 2015)

Have you tried the camping fuels such as Colemans, and the "green " ones like Aspen if you can get them down under. These are a good substitute for pump fuel but won't work as a replacement for methoanol fuels glow engines.

If you want to use LPG then you need a demand regulator that senses the vacuum in the carb as the engine sucks in air/fuel and opens then closes off for the remaining cycles.

Tip 3 on this page shows details of one, there was also a design in model engine builder mag

http://www.floridaame.org/HowTo2.htm


----------



## KLG (Aug 16, 2015)

Hello Chris,
I routinely use Shellite.
Cheers,
Kerry from OZ


----------



## oneKone (Aug 16, 2015)

Cheers for both replys. @jasonb sorry I replied earlier but it didn't get posted. 

I recently found out that I'm allergic to 2 stroke oil (mineral) so I can still use pump fuel luckily. 

@KLG would you know if a different compression ratio is needed for shellite? 

Cheers,
Chris


----------



## Jasonb (Aug 17, 2015)

The Shellite is naptha based like the Colemans fuel and I have not found the need to alter any settings, this is mainly on hit and miss engines but my 4 stroke aero engines also run fine on it


----------



## KLG (Aug 17, 2015)

chris001 said:


> Cheers for both replys. @jasonb sorry I replied earlier but it didn't get posted.
> 
> I recently found out that I'm allergic to 2 stroke oil (mineral) so I can still use pump fuel luckily.
> 
> ...


Hello Chris, 
Jason B is quite right regarding CR.
 With low speed model engines the effective CR is usually a lot less than the calculated CR because of the closure point of the inlet valve. 
Shellite has a  few of the components of pump fuel(up to 30% n hexane) but minus the toxic components (benzine) and is much safer(toxic wise) than regular pump fuel. You will not damage anything trying the fuel and you will be using a much safer compound.
Cheers,
Kerry from OZ


----------

