How to Make a Carburetor - Propane Conversion for Small Engines

This video is part two of the Propane Bike Project series. I am taking a 50 year-old Briggs and Stratton engine from the scrap heap and using it to make a propane powered pedal bike.
In this video I demonstrate how to make a propane carburetor from Home Depot parts.
Propane Bike Project FIRST VIDEO: • How to Power an Engine...
Propane Variable Regulator:
www.amazon.com/dp/B096CRXM43?...
Garretson Style Regulator: amzn.to/3MuXOyY
As an Amazon Affiliate, I earn a small commission from qualifying purchases.

[@stevemcconnell1313]

Thank you so much. That really helps me out. Modifying a wood chipper from 4 hp gas to 11 hp Briggs propane. 👍

[@stephenpaul9165]

Love the t shirt dude 😄

[@GuerrillaShop-m3]

Thanks man!!!

[@stevemitz4740]

Today I ran a 3/8 ID hose from the worthless TEMU $20 multi-fuel carbs, regulator, 3/4" in. into the carb on a 6 HP Tecumseh generator, it worked fine, I just need to mount & run it properly, through the air cleaner!

[@donaldreadenour3776]

Re-key the flywheel so that the spark is as close to TDC as possible. Use a copper or steel capillary tube inserted into the intake port AS CLOSE AS POSSIBLE to the intake valve without causing interference to the valve. Have a needle valve controlling the flow to this for the idle circuit. Have another copper or steel tube, somewhat larger, also terminating next to the intake valve, but have it connected to a valve to control speeds above the idle from the first mentioned circuit, this is the acceleration circuit. The beauty of this setup is that you don't need any air modulation (no air throttling or throttle body) and that you can use methane, butane, propane, or any other gas without any jetting modifications, just idle speed adjustments...

[@GuerrillaShop-m3]

Thanks for the advice! Makes perfect sense.

[@brianlavigne3579]

Great experiment. Thanks for sharing. You made me nervous with your hand near the flywheel.

[@GuerrillaShop-m3]

Thanks man! Sorry I made you nervous 😜

[@87octane2]

great video, i am gonna try to replicate this with a ford 302

[@FordbyFor]

Dude that’s literally what I was researching to do w a 370, haha, nice

[@87octane2]

Running on propane would need a lot of advanced timing, like about 20 to 20 degrees@@FordbyFor

[@willyck948]

Any questions just ask I've messed around with a few propane conversions. I buy parts from ebay seller Propane-kits and also have a few mixers I can compare to gasoline carbs. I also plan on converting tecumseh carb in the future.

How do you put oil in the engine? When you use a two stroke engine, you mix the oil on the gas, but how do you do put oil here?

[@FordbyFor]

Awesome! Hey do I think there’s a way to plumb it next to the carb so you could switch back and forth from gas to propane? All the kits require you changing the carb but would be cool to have both on hand. Great explanations, thank you

[@FidgetBlips]

Still love your channel intro 😂

[@GuerrillaShop-m3]

LOL! I'm just a goof ball with ADD...

[@swalowit]

Hey man.. Nice Job !! Im watching because im also about to start experimenting. Got a bunch of small 4 strokes from all my homemade toys over the years. When you said in begining with direct injection it wouldnt idle up my thoughts immediatly went to that there was no oxygen able to mix and pictured in my head that air opening in between the adjustment knob and burner on any Gas Grill. So when you first started showing your PlumberCarb i figured the Propane was going to go through the 45° and straite shot through the Tee with the Air getting sucked in at the 90° of the Tee. Like a typical venturi type suction pump. So my question is now with your experiences do you think that might work any better ? Different ? I would think that with the propane going straight and picking up its oxygen through venturi that maybe through experimentation, maybe enlarging, reducing inlets & outlets of the Tee you might be able to get to a point where you only have to adjust the propane and itbself regulates Air intake ? Oh wait you did mention building a venturi carb i think ? Did you show that design in a video and was it basickly what im describing ? Honestly i havent even looked to see how they design the Store Bought Conversions yet, your video was the beginning of my research. Im think im going to start with scaveging everything off my old gas grill in back, possibly using the valves for throttle and the air mixing section and start experimenting. I saw a comment about the regulator ? Is that necessary or no ? THANKS !!

[@GuerrillaShop-m3]

Hey, thanks for your comment! My experience with running a small engine on propane is... it's very finicky. I would just order a conversion kit, but nobody makes a conversion kit for a 50 year-old Briggs and Stratton engine. I did machine a Venturi and set it up with the same structure as a typical carb. The engine ran, but it was rough and I was not able to control RPMs. I have concluded that a Venturi is not needed because the propane is a gas and already has pressure. I believe it all boils down to ratios and getting perfect: air vs gas. You might want to check out my other video on using propane to power a small engine. It might give you some ideas. At any rate, please keep me posted on your propane/engine adventures. I am very interested!

[@selador11]

I'd like to do this as well. Only for a generator, so not so much variable needed, and without the garretson.

[@GuerrillaShop-m3]

Yeah I tried without the Garretson and it was the same… Good luck. Let me know how it goes!

[@calysagora3615]

@@GuerrillaShop-m3 Same here, looking to convert a couple of generators. Did you come up with a compact unit? I see you didn't post in a while, I hope all is well...?

[@GuerrillaShop-m3]

Got sidetracked for a bit. Plan to get back to it later this summer😊

[@paultrauzzi5360]

Never use a ball valve for flow control. You can get or even convert a ball valve into a "characterize" unit. Look it up.

[@mkeyengineeringservices4378]

Would this work for a regular generator

[@GuerrillaShop-m3]

I don’t see why not. The connection to the engine may be a little different but the concept is the same.

[@bernardpoole9123]

I see no way for the propane to shot off if motor stops ( very dangerous)

[@Beechnut985]

REF

[@egjorgov]

Why all the stupidity, buy from a lie press an evaporator na a carb plate for $15 and it will rev up to 5k

[@Beechnut985]

LNG.REF