3000W Chinese Gensets Info.

olephart wrote:
That's good news. It's nice to have options. I thought I was finished bothering you with questions, but I was wrong.

I noticed a photo many pages back where you had the regulator mounted 90 degrees from upright. This would be best for my installation.

Was the Garretson happy when turned on it's side?

I also noticed a few photos where the adapter block was placed between the engine and carb. Others were placed between carb and air filter.

What did you decide was the best location?

The position of the regulator is unimportant as long as you can keep water that might corrode or collect and freeze from entering around the primer button opening. (Note: Some manufacturers and models do specify the mounting position or orientation of the regulator. Always follow the manufacturer's directions.)

Where to place the adapter block? In very simple terms and without a full physics based explanation of airflow and the venturi effect:

Engines that run at a constant RPM (like a synchronous 3,000 watt class Chinese generator) perform well with the block in front of the carburetor (i.e. in front of the throttle butterfly plate). Since the throttle butterfly maintains a relatively stationary position, air flow that creates the negative pressure required to draw LPG into the engine remains constant, allowing for a simple one time mixture setting for the load block - which is placed between the low pressure Garretson type demand regulator and the adapter block.

When the adapter block is placed between the carburetor and engine (i.e. behind the throttle butterfly plate) air flow is reduced when the throttle butterfly closes but vacuum from the slowing down engine will continue drawing LPG into the engine. When the throttle is reopened the engine loads up from the excess LPG and bogs down - perhaps even backfires.

When the carburetor is "drilled" the fuel feed point does not change from that of petrol. The tube is smack-dab in the middle of the venturi where the carburetor body narrows and air speeds up to siphon petrol out of the float bowl lying underneath (also between the choke/intake and throttle butterfly/engine manifold. This position is the best choice for engines that run over a full RPM range - it is also the most invasive and destroys the option for multi-fuel.

"Some" carburetors that have a greater physical mass will have room to drill a new opening into the venturi, which adds a centered feed for LPG as well as gasoline. This is obviously the most efficient for dual fuel on an engine where speed is not constant.

A feed block behind the carburetor is NOT an option for your fixed speed Chinese generator engine.