The "LP" trick... but on a generator

[ps2fixer]

I've mentioned this trick a few times for testing if a machine has a fuel related issue (carb issue, blocked fuel line, plugged up filter in tank, etc). Can't get much more detailed than a video. Only difference is I use a portable LP torch. Figured this might help someone out, just remember this is a "do at your own risk" type of thing. There's a very slim chance a back fire could light the torch (I've never had it happen), and also be mindful of how much gas is coming out. Like don't stick the torch in with the valve opened and walk away, then come back to try to start the machine. Same principle as starting a grill, you don't want to make a small bomb lol.

This works with flooded engines pretty well too with fuel turned off to the carb, no choke, etc. Ultimately this is like starting fluid, but it doesn't wash away the oil on the cylinder walls so there's no wear/damage to the engine from using this trick often, in fact as the video shows, you can run an engine directly on LP.

The principle is the torch (and grill controls) premix the fuel with air, so as long as you put out about the amount of fuel the engine needs to run on, it will easily start. I've never ran into the "too rich" condition like the video shows, but I didn't use grill controls either.



The video makes me want to convert my generator to LP since it has a bad gas tank (can only fill half way). I bet it's easier to cold start too and the carb becomes just a air/fuel volume control to keep rpm in check.

[El Camexican]

Pretty much every commercial use non-diesel truck in Mexico runs on LP. There are stations all over the place.

If you want to see an engine that runs off of gas in the air look up the Arrow engine Company in Oklahoma. Those old beasts power oil pumps when electricity isn’t available. The carburetors just take whatever Natural gas is spewing out of the hole and somehow manages to run on that without blowing anything up by means of a governor. It is about the most ecologically unfriendly engine you could ever imagine, but they’ve been getting the job done for over a half a century.

[ps2fixer]

I read they were common in Europe, didn't know it was common south of the boarder too. I guess USA is just behind the curve on alternative fuels. LP powered road vehicles are so rare here that I can't find much info about regulations here. Like our gas and diesel has road tax on them, but LP wouldn't have the tax, same deal as with "recreational gas" aka E0 "real" gas. I know it's illegal to run off road diesel or kerosene in a diesel vehicle and they die the fuel system red to try to catch people. I know it's possible to do it legally, my grandpa had a diesel truck converted to LP way before my time.

The other engines sound interesting, are they natrual gas hit and miss engines? Those are an interesting tech, engine is always wide open throttle, and it only gets fuel/spark when the rpm is low enough, so it can fire once and spin for 10+ turns before it fires again, put a load on it and it fires almost every other turn (4 stroke engine).

[El Camexican]

I see a lot of Mexican trucks crossing into Texas with LP systems, so I don’t think it’s illegal, you just have to make sure you have a source.

You can run a diesel engine on used cooking oil as well, my cousin made it all the way down to Nicaragua and back In an old Jetta, no laws against it.

I don’t know if you would call those engines hit and miss, but they do have massive flywheels so I’m sure they could skip a few revolutions and still keep running. I knew a lot more about them about 12 years ago, but I think the issue was more about keeping them from over-revving due to being constantly immersed in fuel.

[ps2fixer]

Yea, not sure how the laws are exactly, never looked up the real law, but there's road tax on fuel to pay for road maintenance and repairs, new roads etc and pretty sure it's a requirement to pay it to be on the road, atleast by the books. That's atleast how michigan is setup, not sure about the other states since I'm pretty sure the tax is a state level thing.

For the hit and miss engine, this is what I'm talking about. Got probably 8 or so oil wells in my general area with this setup. I don't think I've seen one running in like 20 years though. You can hear when it fires vs misses, super efficent engines at idle, like they run on almost no fuel just to keep going, while under a load and it's firing every time, it's similar efficiency as a normal gas engine.




Also... found a bug on the forum, the embed youtube plugin doesn't work with youtube's shorten url such as this link - https://youtu.be/I53TsWvcEes?t=36