Type 4 Kit

natural gas generator conversion kit

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We have Professionally Equipped Yamaha Generators Ready to run on Propane, Natural Gas and Gasoline. Click here to learn more . . .      Want help figuring out which kit to order?  First try our "What Kit Do I Need?" page and

also the new "Simple Explanation" page!





Some Kit Order Links on individual pages are no longer functioning.  We apologize for the inconvenience during this website update.  If the ones on your page are not functioning, please verify what kit is available for your unit and then

click this link "KIT LIST PAGE FOR ALL GENERATORS AND ENGINES" to go to this temporary kit listing page.


Search for any Generator or Engine number. See results below:


Help Links


ALL ENGINES 12hp or smaller use

A & C Kits


ALL ENGINES 13hp or Larger use

Type 1 Kits

Dedicated High Pressure Propane


Type 2 Kits

Bi-Fuel Propane and Gasoline


Type 3 Kits
Dedicated Natural Gas and Low Pressure Propane

Type 4 Kits
Tri-Fuel Natural Gas, Propane, and Gasoline


Remote Start
The parts needed to start a generator remotely by wire or even wireless


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Don't know what kit is best for your application?

Click this link for a Simple Chart that should help you decide what is your best kit choice.

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Thursday August 05, 2010

News & Features

Kit Production Update:


 is currently at:

1-3 days

As always, some kits take a little longer due to heavy order volume. 

Kit Center Regular Hours of Operation:

Monday thru Friday

9:00 am - 4:30 pm

Eastern Time.


If you require assistance please fill out a request form using this link

Tech Help

 or the email address found in your Master Conversion Instruction Booklet.




Use your credit card and safely and securely  order on-line.  Or call our office toll free at :


 Monday thru Friday 9-4:30 Eastern time.  You can place your order over the phone if you feel more comfortable doing that or if you would like to speak with a company  representative to answer any further questions you may have. 

Please check our BASIC INFO page first.




For our Canada customers call us here in the U.S. toll free at




reg&adpn.JPG (68306 bytes)

Photo of an Adapter Installed on a Tecumseh HM100 Engine
Click for larger view

Type 4 kits are Bi-fuel: Natural Gas and Gasoline.  Actually they are also considered Tri-fuel: Low Pressure Propane, Natural Gas, and standard Gasoline.  The photo above illustrates how most adapters install on an engine.  Adapters are just that. They adapt to whatever carburetor an engine has and are installed between the carburetor and air cleaner. Above, you can see the adapter is between the carburetor on the left and the air cleaner assembly on the right. 

This is basically how they work:

venturi.jpg (14790 bytes)The Adapter has a hose running to it from the demand type regulator supplied in the kit. The center of the adapter has a venturi.  A venturi has an opening in the middle the shape of which resembles a doughnut. All around the edge of the center opening are many small holes. As air passes through the center opening and over the many small holes, fuel from the regulator is delivered to the air stream. How much fuel depends on how much air is passing over the holes which depends on how far the throttle is open based on the governor. 

People often ask about power loss with the adapter style kits. We have never had a complaint about power loss with any of our kits. 

After the installation, the engine should be tested right away on gasoline. If a reduction in performance is noticed on gasoline you may choose to remove the adapter when using gasoline. This usually takes only a few minutes though it is often not necessary.

So basically, adapter kits are not a conversion, they are an adaptation.

Low Pressure Bi-Fuel Kit Type 4 Price For Most Engine Brands Including Some V-Twins:



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in the U.S. at 1-800-553-5608

or toll free from Canada to our US office 1-800-486-0077.

US Carburetion Kit Center

416 Main Street * Summersville * West Virginia * 26651

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