As the instructions from propanecarbs.com suggested, the actual conversion kit install took very little time, what took up my time was adjusting the propane to air ratio after the propane conversion so that the engine ran smoothly and started easily.
This is important because the air/fuel ration is much more critical when burning propane, it burns leaner than gasoline, because it has less BTU’s by mass so it is easy to adjust the fuel so that their is not enough fuel to burn, it is also temperamental in that it ignites at a higher temperature so it easily becomes too rich to burn.
The kit is able to fit on a wide variety of engines so it does take adjustment, the instructors say to set the fuel adjustment needle valve in the middle range by screwing it in fully the, backing it out 6 to 7 turns. This should allow most engines to start.
Once the engine is started you can turn the screw 1/4 turns until you get the engine to run smooth.
If you can not get the engine to start look at the following for troubleshooting.
On the beam regulator (flat pancake looking device that) there is a brass cover that looks like a screw that is directly above the propane inlet line coming from the LPG tank. The cover it should be 1 to 4 turns in. Occasionally the screw this plat covers is tightened too much at the factory and since it regulated how much vacuum it takes to allow fuel to flow through the regulator – if it is backed in too deep the generator will never run.
Check your spark plugs, the propane ignites at a higher temperature so good ignition is more important than when running gasoline.
Check your air filter – its just good mechanizing practice to check fuel, air and spark.
When I did all three – replacing the spark plug, air filter, and ensuring the diaphragm adjusting screw was in the right place the generator started right up just as the instructions said.
I let the engine warm up and then made slight adjustments until it idled smoothly – then tightened the lock nut and showed my wife how easy the generator was to start now.
I’ve wanted to finish the project of converting an engine to propane for years. I mentioned doing it on my lawnmower generator post back at the beginning of my blogging career.
I never got around to it because I thought it would be to hard and I did not want to tear up an engine since, like most of the people reading this post, I simply can’t afford to break an expensive engine.
However, I kept worrying about the fact that I was on the road a lot for work and I did not want my wife and son alone in a cold dark house if we had a bad storm. I also continued to have problems with storing gas and keeping the generator’s carb from gumming up while keeping the generator ready for my wife to start it.
This lead me to call Richard from propanecarbs.com and ask him exactly how hard it was to convert an engine to run on propane.
It did not take me long to realize that using a kit was pretty easy, actually after talking with him I briefly toyed with the idea of offering conversion as a service. So I concluded that he was either a great salesman or the process was exceptionally easy.
Turns out, the process is exceptionally easy. There was not a lot of products in the kit, and it had a LOT of documentation explaining the process. Each kit has some specific parts for your engine, but realize that your engine model may be installed in a generator, a snowblower, a tiller, or anything else the manufacture wanted so the instructions can be a little generic.
Take your time an look at the instructions before you start install, it makes it much easier if you understand how each part works.
The kit I got contained a couple hoses and hose clamps, a high pressure regulator, a vacuum operated regulator, a couple of elbows (one was also a valve), a venturi that bolts to the carburetor, some gaskets, bolts, mounting hardware, and studs.
There will be parts left over after your install so don’t panic if you have a bolt or two sitting around after the thing is installed.
The video shows the process pretty well, from start to finish it took me about 40 minutes, but a good portion olf that was figuring out what the parts were and how I wanted to mount the regulator. I could probably do it again in 25 or 30 minutes (so could a handy person that knew what they were doing)
The basic steps are:
With the large opening in the venturi pointed to the carb, install it between the carb and the air cleaner – there are gaskets and longer bolts to use if necessary.
Install the elbow that has the lock-nut and adjustment screw on the top side of the venturi (unless it won’t fit then use the normal elbow) and point it toward the location you will mount the beam vacuum regulator.
Decide where to mount the beam regulator on the machine you are converting, it needs to be close to the carb, be accessible so you can press the priming button when starting, and be orientated to the vertical – because if it lays on its side gravity will affect the diaphragm and make it hard to operate.
Screw the elbow into the top of the regulator so it is orientated toward the carb.
Install the shorter fuel line to connect the regulator to carburetor venturi – use the hose clamps.
Connect the high pressure regulator that attaches to the propane tank to the beam vacuum regulator
Use yellow gas-line tape on the connections and ensure they don’t leak.
OR – alternatively you can pay me to install the kit for you….
I’ve thought about converting a generator to electric start for years now. Actually, some years ago I bought a generator off of craigslist and decided that pull starting a temperamental 10 hp engine was not something I wanted to do, nor COULD my wife do it.
Since most of the times a generator would come in handy (ice storms) I would be out of town for work, having an easy way to start the generator became a priority.
When I bought the thing I did get a new flywheel installed so the engine would have the teeth needed to accept a starter. I kept intending to add a starter, but I never got around to ordering the parts.
Things to consider:
- Does the engine block have mounting brackets for a starter, if not, then this project is not feasible.
- Does the flywheel have teeth to accept a starter? You can replace a flywheel, but again, the cost and effort may not be worth it for the engine you have.
- If you replace the flywheel, try to get one with magnets for a charging system – mine did not so I have to charge my battery in other ways.
- Do you want a high amp switch or do you want to use a starter solenoid? The high electrical demands of a starter will burn out a normal switch. Personally I used a switch that could work with a circuit from the battery directly to the starter, but I used a solenoid to give myself some mounting flexibility and so I could use cheaper wire.
- How will you get power? For my model of engine I had several options, I had a very simple to install 110volt kit (why would I want my backup generator to start using house current?) and I owned a small motorcycle battery that could fit inside the generator cage (not enough voltage). I ended us cutting off one end of jumper cables and installing terminals that would allow me to permanently install them. That way I have more options when starting my generator, as I can hook it to any car battery, even one already in a car.
I am very glad I did this project, and my next achievement will be to convert it from gasoline to LPG using a kit from propanecarbs.com so I can run gas, high pressure LPG, and Low Pressure LPG
Some of my projects are done “just because”, others are experiments or learning exercises, but some – like this one – actually has tangible benefits. So lets talk about the benefits of converting small engines to propane.
The self reliant gain several advantages when converting small engines to LPG from gasoline. Some tout the ecological benefits, but I am going to focus only on the tangible things that make daily life easier for a prepper.
Unlike gasoline propane can be stored forever! It is much easier to buy a 20 pound LPG tank and store it in a shed than messing with additives and rotating gas. Gasoline can only be stored for a couple of months and fuel stabilizers don’t work well with ethanol gasoline.
Propane is not spilled like gasoline when refueling. This makes refueling simpler and safer. You don’t risk a fire when gas hits a hot engine, and you don’t have to wait for the generator to cool – you also don’t have to mess with funnels or other tools. Simply screw in another tank and start the engine right up.
While propane does have less BTU’s of energy than gasoline, so more propane is needed to power an engine than running the engine on gasoline, but less energy is waster when burning propane – the engine run cooler contributing to a longer engine life.
Not only does the cooler operating temperatures extend engine life, propane does not gun up carbs like gasoline, nor does it deposit carbon on the piston heads. You get a longer service life on engine oil and don’t have to worry about rebuilding carburetors. As a matter of fact, in my experience when first converting a small engine, you get black exhaust from the propane helping remove deposits.
Propane does not absorb water like ethanol fuels, nor is it corrosive to seals and gaskets like ethanol fuels are.
Propane in the 20 or 100 pound cylinders is also much easier to transport than the equivalent amount of gasoline.
Next up is how to actually convert an engine using a kit from propanecarbs.com