Originally posted by Sport_Pilot
The glow plug in a glow engine IS NOT kept hot by the combustion that takes place in the cylinder.
Not true the first glow plugs did not have platinum in their alloy. The catalytic reaction inhances the performance, it is not the primary reaction.
/// You are wrong, Sport_Pilot. The first, non-Platinum glow plugs were not even put into production. Without this catalytic reaction, which IS the primary reaction, the secondary heating due to the combustion process IS NOT enough to keep the engine running.
You can try to run a glow engine on gasoline (Neoprene fuel tubing and a gasoline only tank...) and you will see that it shuts off the second you stop heating the plug electrically.///
If you put a drop of methanol on a glow plug, it will not start to glow by itself.
There has to be a reaction in the first place for the catalytic reaction to work, i.e. the fuel has to be burning.
This, because platinum has no catalytic reaction with gasoline.
Not true, the catalytic converters in our automobiles have the same reactions going on and they work very well with gasoline.
///Platinum is also the catalyst in an automobile catalytic converter. But there it converts Carbon Monoxide and Hydrocarbons into harmless water and Carbon Dioxide.
It does not break down methanol, as there isn't any. The CC also needs to be very hot to function correctly and combustion does supply the needed heat.///
In fact they work best with nitro because nitrogen sticks to the catalytic element exposing the carbon and hydrogen elements to make a quicker bond with oxygen. Of course without nitro they work with the nitrogen in the air.
///May be true, but glow engines do run on FAI fuel, using a hotter glow plug and more compression.///
See the SmartPlug thread.
///A methanol fuel engine can easily be run on spark plugs, as they are. But in order to run a gasoline engine with glow ignition, you must supply constant electricity to the glow plugs; no catalytic self ignition.///
Also do a search on catalytic converters and how they work.