I have had this in the back of my mind for years and this summer we had an extended power outage and all the local gas stations had no power so no convenient gas. I saw a YT video about a month ago and did some research and decided to take the plunge. I can still run gasoline so not much other than a little time and money to lose. The basic parts of the system are the gas piping from the house to the garage, the hose from the gas pipe to the demand regulator (acts like a float bowl), adding a means of adjusting the mixture to the regulator and making or buying an adapter/venturi/mixer to the carburetor. You can buy kits for most generators but I wanted to see if I could do it myself.
I installed a gas line in the garage for an IR heater so just needed to tap into that, add a drip leg, shutoff valve and (later) a quick connect for the gas hose. The gas hose came from Amazon and had a quick connect on one end and a flare connection on the other.
The next big piece was the demand regulator with a means to adjust the mixture going to the carb. The demand regulator is closed until it sees a small (0.3 inches of water vacuum, if the engine stops or the hose becomes disconnected, the regulator shuts off the flow. Basically, it acts like a float bowl. The regulator is a Garretson as that seems to be what everyone is using and the specs. looked good to me, with all my extensive experience...
The mixture adjustment was provided by adding a tapered 3/8" bolt to a standard 1/4" pipe tee. These are available commercially for around $25 but the ones I have seen just had a plain bolt, maybe it works fine but I wanted more of a needle valve, so I tapered the end of the bolt.
The next big "chunk" was the carb adapter/venturi (to provide the vacuum to the regulator)/gas mixer. These are also available commercially for about $50 but, I have a lathe so I made my own out of a piece of aluminum plate.
I got it all hooked up temporarily using a piece of air hose, eventually I will replace it with a piece of gas rated hose but this is good enough for a test.
I pulled the starter cord about a zillion times (felt that way anyway) while adjusting the gas mixture from all the way closed to full open but all it would do was give the occasional "cough", usually after giving it a shot of gas by hitting the "prime" button on the regulator. It was getting late, and dinner was calling so I figured I'd leave it for the next morning.
In the morning, it dawned on me that I had put pipe plugs in the regulator vents (doh!!
) and never removed them for the test. I removed the plugs, and it seemed like it wanted to start more than before but still no joy. I pulled the hose off the adapter and gave a shot of starting fluid into the hose barb and BINGO!!, it started on the first pull. It was running pretty rough so I adjusted the mixture until it smoothed out. I adjusted the "mixture screw" in until it sputtered, then out until it sputtered again and set it midway. I then plugged in two space heaters totaling 3000 watts and it took the load smoothly and continued running well.
I tried to attach a movie, when I figure it out, I'll add it...says it's too big.
The final test will be shutting off the power and simulating an outage and seeing how it compares to its normal-gasoline operation. I figure worst case, if the power loss is noticeable, I will have to be more careful about how many things can be connected at a time. I think it helps that the motor is a 9 hp when 8 hp seems more typical for this size generator. (3500W/4000W surge)
Now we will see if all the horror stories of NG conversions burning exhaust valves are true, I have my doubts but we shall see...
I installed a gas line in the garage for an IR heater so just needed to tap into that, add a drip leg, shutoff valve and (later) a quick connect for the gas hose. The gas hose came from Amazon and had a quick connect on one end and a flare connection on the other.
The next big piece was the demand regulator with a means to adjust the mixture going to the carb. The demand regulator is closed until it sees a small (0.3 inches of water vacuum, if the engine stops or the hose becomes disconnected, the regulator shuts off the flow. Basically, it acts like a float bowl. The regulator is a Garretson as that seems to be what everyone is using and the specs. looked good to me, with all my extensive experience...
The mixture adjustment was provided by adding a tapered 3/8" bolt to a standard 1/4" pipe tee. These are available commercially for around $25 but the ones I have seen just had a plain bolt, maybe it works fine but I wanted more of a needle valve, so I tapered the end of the bolt.The next big "chunk" was the carb adapter/venturi (to provide the vacuum to the regulator)/gas mixer. These are also available commercially for about $50 but, I have a lathe so I made my own out of a piece of aluminum plate.
I got it all hooked up temporarily using a piece of air hose, eventually I will replace it with a piece of gas rated hose but this is good enough for a test.
I pulled the starter cord about a zillion times (felt that way anyway) while adjusting the gas mixture from all the way closed to full open but all it would do was give the occasional "cough", usually after giving it a shot of gas by hitting the "prime" button on the regulator. It was getting late, and dinner was calling so I figured I'd leave it for the next morning.
In the morning, it dawned on me that I had put pipe plugs in the regulator vents (doh!!
) and never removed them for the test. I removed the plugs, and it seemed like it wanted to start more than before but still no joy. I pulled the hose off the adapter and gave a shot of starting fluid into the hose barb and BINGO!!, it started on the first pull. It was running pretty rough so I adjusted the mixture until it smoothed out. I adjusted the "mixture screw" in until it sputtered, then out until it sputtered again and set it midway. I then plugged in two space heaters totaling 3000 watts and it took the load smoothly and continued running well.I tried to attach a movie, when I figure it out, I'll add it...says it's too big.
The final test will be shutting off the power and simulating an outage and seeing how it compares to its normal-gasoline operation. I figure worst case, if the power loss is noticeable, I will have to be more careful about how many things can be connected at a time. I think it helps that the motor is a 9 hp when 8 hp seems more typical for this size generator. (3500W/4000W surge)
Now we will see if all the horror stories of NG conversions burning exhaust valves are true, I have my doubts but we shall see...
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