Sounds like some big fish tale to me.

My Dad is the Pope!

I seriously need help! I have a generator that could be 20 years old. When I bought it I was told that it had been fueled with natural gas. I put the orifice back in to run on lpg. My generator has a random backfire and I feel like gas flow is an issue. My gas guy hooked it up with a 3/8” od soft copper line to a secondary regulator and 3/4” line from that regulator to the unit. I feel like I should have 1/3” black pipe to the regulator which is only 13’ away from the tank. Can anyone advise me?

Yes I've been wondering how this works

Larger engines like trucks that run on propane are required to have another positive shut off, which would be the solenoid.

I was just curious could you just use the adjustment on the regulator to adjust the amount of gas going to the engine instead of using the extra metering valve on the outlet. I've seen a few videos where there's a few folks doing this.

BadCatKharma did you ever try out running your generator on natural gas? I have the same question. Do you know if it works?

The generator may run when hooked up without this kind of regulator but it either run too rich or too lean depending on the load and valve settings on the tank. It would be sketchy.

Another KN will probably work just fine. The variants in models are: (1) PRIMER: Some have no primer, some a manual button prime; another with a solenoid attached for priming. "Priming" in KN regulator lingo means the unit allows some gas flow to the metering unit at the engines "carb"/snorkel/ propane gas entrance. (2) FLOW RATE: Standard KN models have a 3/8" orifice and high flow have a 1/2" orifice. The Horsepower rating for LPG/NG are 40hp /25 HP for standard flow and 50HP/30HP for high flow. (3) INLET PRESSURE Recommended: 11" W.C. or 7 " W.C. A model typically used for Natural Gas often uses the 7 inches of Water Column type and ones for Propane often use the 11 " W.C. one. The SPRING inside is the difference. The Natural Gas spring is RED and 4oz and the stronger spring is GREEN and 6oz. (4) 039-128 might be just an OEM version or spec for you generator. An OEM version can be the same or have a different spring, different exit threading or might just be one where they block off the adjustment so folks will not fiddle with it.

I'm not the guy that made this video but I don't see why it wouldn't work. You must be doing gasification running off the fumes of gasoline. I'm pretty sure guess a vacation is more fuel efficient than propane. They say propane is 130 octane and you use the same kind of pipe dope for gasoline and I think propane and natural gas. It would actually say at the store on a bottle of pipe dope or online somewhere. The people at the regulator company may know whether it would work and not wear out early. In my 9200 lb truck at interstate speeds at 70 miles an hour with the AC and cruise on. I get about 11 miles to the gallon. Running the truck around 40 miles per hour with AC and cruise on I've gotten 42.5 miles to the gallon. Slowing down makes a world of difference and turning less RPMs really increases gas mileage too in anything.. When I'm at 40 miles per hour in my truck I'm only turning 1,150 rpm's about.

Not opening diaphragm because of low vacuum Check carb gaskets

@@philliphall5198 interesting. I finally got it to work on natural gas but I need to have the choke on first. Once it starts to run then it stays running. Could it still be the gaskets? Thanks

No. Most American made last for years

Gaskets on the air/fuel trane can deteriorate and cause vacuum leaking which can affect how the engine runs. Backfiring can also be the result of a leaking intake valve caused by wear or carbon build up. And yes, the regulator can have problems, particularly a worn seat or diaphragm that leaks/is cracked. You can perform a vacuum test on the diaphragm or disassemble the regulator to do a visual inspection to see if it needs replacement. They make rebuild kits to restore the regulator function.

The negative pressure increases on the outlet side and allows more of a free flow of gas

Yes, but make sure the rubber parts are compatible and the pressure in is right.

Yes! For SMALL Engines only! Here... Specs: carbturbo.com/product/impco/

*Your problem is what that inferior quality generator that you purchased from Harbor Freight, which sells directly from in red China. Son, you get what you pay for.*

@@dr.pickle5842 What's it feel like to be a complete tool, AND wrong, all at the same time, son?

The Demand Regulator is more than a cut-off. The Demand Regulator meters out the vapor based on the volume of air through the "carb area" ie throat of the intake manifold. Without a demand regulator, one has to manually adjust the flow of gas. ie like this video here where I just use a dropping BBQ regulator and no demand regulator. kzfaq.info/get/bejne/qb59aLuL3Lu0gY0.html

The "converted" gasoline engine runs on Vapor. It can be either Natural Gas like what is plumbed to a building; or Propane like come in bottles or tanks. Propane in the bottom of a tank is liquid and the outlet is up so only the gas /vapor is used. If one tries to run a 2 Kw generator off a very tiny propane bottle for soldering the generator will not run long since the bottle is too small and one cannot extract enough vapor fast enough. A grill BBQ sized 20Lb propane bottle runs my 2kw generator just fine. A gasoline engine runs on vapor too, the carb atomizes the gasoline into vapor and hopefully very little liquid is at the pistons!.

3beltwesty How does the power the engine makes compare when running on Propane compared to running the engine on gasoline?

I realize this post is a year late but folks may find this helpful...... 1.) Both! This demand regulator measures the vacuum created by the engine and increases/decreases volume flow based upon this changing vacuum pressure. If no vacuum - no flow of gas vapor. Of course, the demand regulator must be setup properly to function with your specific low pressure supply just before the demand regulator inlet valve. More on that later..... 2.) Yes, factory setting, as marked on the demand regulator, is 6 ounces or 10.379 inches of water column ("WC). This is appropriate for typical low pressure propane. If you are demand regulating natural gas supply from a residence you might ask for/order a 4 ounce (RED) spring which is equivalent to 6.919 "WC. This particular spring pressure is appropriate for a typical home where the low pressure, after the meter, is 5 - 7 "WC. 3.) No, the inlet valve does not work that way. I follow your thought, though. Just before the gasoline engine intake valve, the mixture of the fuel gas & air moves in a somewhat staccato fashion. Stopping and starting as the intake valve opens and closes. But, the farther away from the intake valve, the smoother the flow or velocity of the mixture becomes. At the demand regulator, the vacuum or negative pressure is either constant (HIGH IDLE), increasing (ACCELERATING), decreasing (DECELERATING) or non-existent (OFF). Gas flow rate at the demand regulator inlet valve is therefore constant at HIGH IDLE, increasing, decreasing or stopped when engine is off. 4.) Very good question. Small engines don't require an electrical solenoid switch to physically shutoff fuel supply in the case of the engine crank not turning. But, you could install one anyway. I will not cover all safety issues here but be aware of what vapor fuels do when a spill occurs and how vapors pool. Natural gas rises and propane falls at atmosphere. Always run portable generator outdoors away from flammable items and ignition sources while planning for the worst case if vapor gas pools from a temporary leak. More on that later..... More on setting up your demand regulator properly: Make sure you know what your low pressure supply is just before the demand regulator. Use a gas low pressure gauge. Or, make a crude measurement with the following: take a deep bucket and mark 1" graduations on inside of bucket. Starting at the bottom measure 5 inches up and mark it so. Continue marking upwards, 6", 7", 8" and so on to 14". Fill bucket with water to the 14 inch mark. Make sure no ignition sources are nearby and proper ventilation is at hand before doing the following. With gas supply on, plunge the supply hose to the bottom of the bucket. You should see NO bubbles. If you do, turn off gas supply and call in a professional to fix your supply overpressure. Remember the 8oz marking on the demand regulator? This is the maximum limit of low pressure the demand regulator can withstand without failure. 8 ounces is equivalent to 13.839 "WC so this pressure you just measured of roughly 14 "WC could damage the demand regulator in a bad way. Continuing on with no bubbles.... Slowly, raise the gas supply hose noting when the first bubble appears and stop when you have a nice stream of bubbles. Make a note of the graduated marking on the side of the bucket and turn off gas supply. Hopefully, your crude, low pressure measurement would be in the 5 - 7 "WC range for natural gas and 10 - 11 "WC for propane. Now, with the appropriate spring installed in the demand regulator just above the inlet valve, you can adjust the spring tension. Remove the first screw and set aside. Connect low pressure gas supply to inlet. If gas is escaping from the outlet, turn screw inwards (Clockwise) until gas does not escape. Put soap on outlet for a bubble test. Slowly, turn screw outward (Counterclockwise) until a bubble just starts to form. Then, turn screw inward a half turn or so. Now, recheck there is no gas flow with bubble test. Once set, replace the first screw you removed earlier and tighten to lock in your setting. Now, we have covered the pressure of the gas supply. Please make sure you are supplying adequate volume of gas vapor to your demand regulator. In regards to natural gas: the bigger the hose diameter, the better. Don't starve your demand regulator and engine by scrimping on a 3/8" or 1/2" supply hose when you really need a larger size. With propane: the larger the tank the better. A full tank performs much better providing adequate vapor from boil off than a discharged tank. Tee two tanks together when possible. The warmer the ambient temperature around the tank the better. Extreme cold outdoors is not your friend in regards to using propane tanks to obtain vapor capacity you need for a generator. The last adjustment on the demand regulator is the power valve attached to the outlet. The reason for this fitting is propane and natural gas have different volume mix ratios with air. Propane is roughly 1:24 parts air while natural gas is 1:10 parts air. At any demand rate , a smaller volume of propane would be required compared to natural gas. So, if you are switching fuels, you will need to back screw out (Increase Gas Vapor) when changing to natural gas or tighten screw inward (Decrease Gas Vapor) when changing to propane.

Hi, I need some ideas to solve my problem when my Honda eu3000is runs on load with natural gas . It’s shut off suddenly. I think , there is an adjust problem in the low pressure regulator with the flow in the carburetor. Any ideas to do?. Under no loads conditions runs ok. I tried to move the set point in the regulator but I could not make it work fine.

Not sure if you ever received an answer to this, but the diaphragm most likely is cracked/leaking. They make repair kits for this regulator that include a new diaphragm.

@@commonsense5105 thank you. No one did. Unfortunately, I replaced it with another and had the exact same result. I used it for power outages many times, and after monitoring for hours, I just accepted that it may be normal to have a small leakage from these. I'd prefer none, but mostly 1000 to 10000 max. It never got near the 50,000 LEL to combust. My concern was having a generator tent, is that it may build up in larger concentrations to an explosive limit. Thankfully, testing proved the tent wasn't too sealed off to cause this.

Something doesn't add up. Some regulators will have an internal relief and blow out the vent if the downstream pressure gets too high. A regulator at the meter for natural gas does this to insure the system operates safely and is a fall back safety. This regulator doesn't have that feature, confirmed by talking to Impco who makes the KN unit. The reason the vent is there is it allows atmospheric pressure on the back side of the diaphragm to account for atmospheric pressure changes. One reason the diaphragm is as big as it is, atmospheric pressure is pretty small and a larger diaphragm amplifies the effect of that low pressure. The other side of the diaphragm is where the gas valve is and that pressure, or in this case, vacuum, pulls on that side of the diaphragm to help open the valve. Thar vacuum is created when you go to start the engine, and is transferred to the regulator from the hose that supplies fuel to the engine. That vacuum force is also amplified by the larger diaphragm as its not very strong either. The atmospheric pressure and the suction from the engine are an opposing force working against a spring within the regulator. When the engine is not running and there is no vacuum, the spring overwhelms the atmospheric pressure and keeps the valve in the regulator closed. When the engine vacuum is added to the atmospheric pressure, like when you try to start it or the engine is running, the spring is overcome and the valve in the regulator opens. The more vacuum, the more it opens. Here's the part that doesn't add up. The part of the regulator that contains the natural gas or propane is under vacuum from the engine. This means it would be almost impossible for any gas/propane to seep out of the regulator, assuming the regulator is set up properly. The only place it might leak out would be where the fuel comes into the regulator, as up to the valve within the regulator, its under positive pressure. The only other thing I can think of is the settings are off on the regulator, but normally if there was enough gas to be leaking out of the regulator, it would flood the engine with too much fuel. Any leak on a fuel system is not good. I would suggest using some soapy water, put a little on your finger and try to get it to span the vent hole to check to make sure it's leaking from there and not another fitting near by. You might want to check all your threaded connections for a leak too. Not setting up a tent is a good idea as that could yield in very undesirable results. 😳

@@commonsense5105 thanks for the very thorough explanation. I've replaced many gas regulators, but on-demand regulars pulled by vacuum are new to me. What you say about positive pressure makes sense. Unfortunately, I've sprayed blue all around the hoses and other areas, the leak does come from the regulator itself when running and after it's done running for awhile. Before I start it, there's no leak. My meter is a Sensor HXG-3P, which I calibrate regularly. These are commerical grade testers and do a pretty good job of finding the leak. Maybe I got unlucky twice with a bad batch as the replacement was from the same eBayer, I kept both. On the first one, I tried adjusting the spring pressure to see if it would help.

I worked at a combination natural gas/electric utility for 38 years and been around regulators for that amount of time. Have done lots of autopsies on many failed regulators and its amazing what stories you find when you take them apart. If you still have the first one you had problems with, it would be interesting to disassemble it and see what you find. I understand the need to protect your generator and keep it out of the elements, especially when the grid is down. Hopefully you can get to the root of your problem so you can optimize your backup solution.

One scheme is to add a gas cut off solenoid in series that is open for flow when the generator is on and producing voltage. ie the 120 volts out from the generator supplies the voltage for the solenoid. Thus if the generator is off there can be no Propane flow. The larger generators usually have a scheme like this. The catch 22 is to start one has to manually or via magic gizmo/logic get the gas to flow ; ie to get the unit to start. In an automatic unit this is done so the user does not have to manually fire the solenoid valve. A safety shutoff scheme is required on larger units ; then too the same scheme helps not loose 100Lbs woth of propane too. The Gas cut off valves are often 12 Volts DC and thus the system uses the 12 volt car battery for starting and also to fire hold the solenoid on once the unit is running. ie the solenoid is manually given 12 volts DC to start then after a few seconds the logic uses the generators output changed to 12 volts DC to hold the solenoid open.

I guess what you are saying is your unit does have a cut off solenoid but I guess some trash held it open thus all the LP gas leaked out. ?

why you pay high amount after buy a generator, i use www.generatorkits.co kit. its awesome quality in low price