OT? Propane/Natural Gas Carbs

Impco is one

I've bought their stuff for bigger engines but wasn't aware they did small engine carburetion. I'll check with them. Thanks.

You cannot depend on a generator for emergency power unless you run it regularly. We have ours on a timer and run it for a 1/2 hour every Tuesday morning and power our NOC off generator power during that time. Ours is natural gas.

I would strongly recommend you do NOT mess with attempting to convert a gasoline powered generator over to natural gas. Natural gas generators are completely shielded. With a gasoline powered generator, a small leak in the fuel system is nothing. A drip that evaporates. With a natural gas generator, a small leak in the fuel system means your natural gas falls down and fills up pockets in the low spots in the enclosure. Then when the generator fires, unless it is shielded, the starter will fire the loose natural gas and blow the entire works over the mountain.

Ted

Natural gas does not "fall down and fill up pockets", natural gas rises and will only fill upper pockets. LP gas will settle and fill low pockets. In either case assuming the generator housing is properly constructed there should not be any significant pockets in either direction and the gas should vent harmlessly.

In the OPs case he's talking about a very small portable generator which has no enclosure and therefore no place for any gas buildup. Indeed being a portable unit I expect it will not even have that LP tank connected unless it's actually in use.

Pete C.

What enclosure? This is a portable generator, which I drag around to the side of the garage when I need it. The technology to handle natural gas (or propane) through flexible lines is well known to people with barbecue grills.

As far as running it periodically, I did. But that didn't stop the gas tank from rusting out and clogging the carb. Even using a gas stabilizer and draining the tank didn't help.

Use stabilizer. Keep the tank full to prevent condensation. After using the generator before turning it off, disconnect the load, let it run unloaded a couple minutes to cool off then close the tank valve and let the carb run dry. Once a year if the generator is used infrequently, drain the tank and put the gas in your car to use up. Refill the tank with fresh gas with stabilizer. You should not have any problems this way, certainly I haven't.

Pete C.

The problem isn't getting the gas to the engine. It needs to be fed into the engine at the right mix and even if you solve that adequately your engine has no built in capability to be tuned to run properly on gas.

Newer versions of your engine come with a plastic gas tank that might be fit onto your engine. You can install an inline fuel filter to keep dirt out of the carb.

-jim

Duh. Hence the original request for a supplier of NG or LP gas carbs for small engines!

Right.

I had a '68 Dodge Pickup that ran very well on propane. The equipment for this is readily available (many standby systems are sold to run on natural gas). The problem is in finding suitable conversion equipment from a reputable manufacturer.

I own 2 bikes, a 1980 CB750K and an 81 CB750C and am familiar with the problems of gas tanks rusting, as this is a common issue with bikes that aren't run frequently. Incidentally, I have not had that problem with either of my bikes.

You may have been running it periodically but you wern't running it long enough. What you need to do to keep a metal gas tank from rotting out is to start the generator, then run the gas tank dry. Then turn off the fuel line to the carburetor, and fill the tank up with fresh gas. Then you can let it sit a month and turn it on and run it dry again, then turn off the gas and refill the gas tank. Repeat indefinitely.

No need to use fuel stabilizer if you do it this way. Gas has stabilizer in it when you get it from the pump, it's part of the additive package. You only need stabilizer if your going to let a half-full gas tank stand for months at a time.

Needless to say if your engine does not have a fuel valve between the carburetor and the gas tank you need to add one.

Ted

The gas tank bolts directly to the bottom of the carb. In fact, the carb's 'float bowl' is an integral part of the gas tank. This is a very cheap (and inexpensive) setup. Hence, my desire not to sink any more money into the gasoline carb and go LP/NG.

Pull the carb off, Throw it in the trash and replace it with a carb off an engine that can use a remote tank. Then use a plastic boat tank to fuel it with. I did that with an older generator here. The 5 gallon tank increased the runtime. Being it was a plastic tank there was no rust and I could just unhook the tank, run the carb dry and not worry about it. The new Honda unit I have can be run on gasoline, natural gas or propane. BUT it produces less power on natural gas or propane than on gasoline.