Run an Engine with the GEK

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Saved by jay
on March 23, 2010 at 6:40:00 pm

return to How to Build and Run the GEK Gasifier

I. Convert your engine to run off of wood gas

When connecting the gasifier to the engine, the gas is routed through the air filter canister and a second air mixture valve on the wood gas line is needed to create the wood gas air mixture 1:1 right before entering the engine.

Upgrade the air filter canister to a wood gas carburator system:

Air tight filter canister-Air filter canisters are not designed to be air tight! (On the Honda Accord, we did not notice an extra unpopulated bolt pattern underneath the canister this was delivering leaner mixtures than our controls indicated which caused problems).
The air filter will be used as the last filter before the engine for the wood gas.
The extra T fitting and valve will add extra weight to the canister. They are typically not designed to support weight, make sure your design holds up.
Minimize the amount of stochiometric gas mixture in the system. Place the T for the air mixture connection as close to the air filter canister as possible.
The air to fuel ratio for wood gas is 1:1. However, the air mixture valve pipe diameter will be smaller than the wood gas line. For the GEK, use the existing 1.5'' wood gas line with a 1'' air mixture valve. The vacuum subjected on the system from the engine will more easily pull air in through the air line than wood gas from the GEK system because there is less resistance through the air line. Consider attaching a the air mixture valve at the end of a longer tube or place baffles in the air line.

Gasoline Engine Converstion:

Carburetor gasoline engines are fairly simple to convert. Convert the air filter canister modification (described above). Because wood gas burns a little slower than gasoline, advance the spark timing a few degrees. (Picture of Kholer engine in 10Kw skid (Power Pallet) with automatic air mixture valve).

http://www.gekgasifier.com/forums/showthread.php?t=332

Fuel Injection Engine:

After you have converted the air filter canister to accept a gaseous fuel, next is to cut the gasoline. For fuel injection engines, locate the wire delivering power to the fuel injectors (reference the wiring diagram in the manuel for the enigne) and place a switch in line. Remember, the engine will be a hybrid after the conversion. Important: Do NOT run the fuel injectors without gasoline! You must cut the power if running only on wood gas. Running fuel injectors without gasoline will ruin the injectors.Again, advance the spark timing a few degrees. (Picture of Honda Accord conversion with Dino Fuel Injector Cut-off Switch)

http://gekgasifier.pbworks.com/How-to-Make-a-Woodgas-Carburetor

Diesel Engine Converstion:

Adding a small amount of diesel/bio-diesel reduces the auto-ignition temperature of the mixture, allowing it to ignite at a reasonable compression For this reason, diesels must run in a dual-fuel mode which supplements a small amount of diesel/biodiesel with the wood gas that provides the spark needed to ignite the wood gas. Most turbo diesel engines are not appropriate for wood gas conversion because compression ratio can exceede the compression ratio optimal for wood gas combustion.

Spark Conversion for wood gas Diesel (advanced):

By using a spark plug, no additional fuel needs to be used to ignite the mixture. This was demonstrated at the APL workshop in February 2010. We converted a Lister diesel engine was converted to a 100% wood gas engine by using a Hall Effect sensor on an Arduino microcontroller that controls a spark plug added to the engine.

II. Run the engine off of wood gas from the GEK

This section assumes that you have properly assembled the GEK and tested the wood gas to ensure that your gasifier is producing quality wood gas given the characteristics of the biomass that you are using. If you introduce tarry wood gas into your engine, it will damage your engine by sticking the intake valve. To ensure this does not happen, use dry biomass, make sure that you are within the proper temperature and pressure range in the reactor, double check seals on the gasifier, and make sure filters are not spent.

The Hand-off:

A) Turn off the Flare:

1. Make sure the flare is steady in the swirl burner. The flare should be down inside the swirl burner with the flame terminating before reaching the top of the burner.

2. If you have hooked up propane to the ejector venturi line, make sure that the valve and take are OFF. The wood gas flare should be sustained with out supplementing other fuels.

3. At the same time, close the air mix valve (a) and the ejector venturi gas valve (b). This should be done in a way that does not expose the operator to any wood gas from the air mix valve.

a) b)

4. The open the gas valve to the engine (c), while closing the air compressor valve to the ejector venturi (d).

5. Start the engine in a 'wood gas rich mode' by closing the engine's air mix valve. There might be air (or a lean mixture from the previous run) in the line between the engine gas valve and the engine. This is the reason that the engine should be started without adding extra air into the line.

6. Once the engine is pulling wood gas through the line, it will start. Open the air mixture valve slowly and find the appropriate air to fuel ratio for the engine.

III. Shut down the GEK

To properly shut down the GEK, run it in flare mode.
Turn down the ejector venturi down low so the pressure reading on the manometer is around 1''H2O.
Wait for about 3-5 minutes or so, then close the gas valve to the ejector venturi, place a cap on the air inlet on the reactor, and close the air compressor valve on the ejector venturi.
BE CAREFUL: if any gases are released upon shut down, be sure not to expose yourself or others.