4 stroke Propane ??????????????????

M

Member 5549

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Has any one tried to convert a 4 stroke to run on LPG.
I was thinking it would be Cool to use the 1lb screw in propane bottles like I use for my camping stove, You can buy a refill kit and recharge them from your 5 lb. Gas grill bottle, and could carry a spare or 2 safely.
Just need the regulater and carb issues worked out..
Talk about Clean Burning.
:cool:
 
That the drawback..

I drove a 5 ton truck in Montanna that had a LPG conversion and it was gutless,, Going up the moutain roads full loaded I think I got like 20-30 MPH Full Throttle.
 
The regulator might be an easy hack, get an ajustable regulater for a oxy acetlyne setup, modify the fittings, the tough part is the carb. the smallist propane carbs i have seen are on propane buffersand they would be to big. the smallist propane buffer I have seen is 6-8 horse power.
 
Most floor polishers as used by shopping centres are a 4 stroke engine, running off a 9kg gas cyl (cant use petrol indoors for obvious reasons).

There is no reason why not - another thing to consider is the butane cartridges for those little cheap camping stoves...
 
This could be done- I'd like to see someone do it....not going to be me, though. Takes me over a year to finish one bike.
 
It would be nice if some one would offer us a kit. till then it is on my wish list. I already have to many projects going.
 
The carb bowl atmospheric vent must be located and plugged. Remove the carb needle valve. Connect the propane hose to the fuel inlet nipple on the carb.

I would think it gets tricky without a variable pressure regulator (see my idea below). Propane requirements will be different at wide open throttle and under load as opposed to idle and no load.

Or, how about this: A propane storage tank running to a 'fixed', but adjustable pressure regulator to drop the pressure to a workable level. Then from the regulator, a hose to a ball valve with a lever, to control the valve opening manually, mounted on the handle bars. The ball valve could be limited in it's closed position to allow a metered amount to reach the carb for idle purposes. Slowly opening the ball valve would increase flow to the carb, in tern, the engine RPM and torque increase. The pressure regulator could be adjusted to suit full throttle requirements under load by dialing the correct line pressure for the best full throttle performance.
Your engine oil would certainly last a lot longer!!

Running propane on a fixed RPM engine is easier, such as a generator set, etc.
 
You are over-complicating it, you can make a vw or ANY other carbed 4 stroke run on propane just by drilling a hole in the carb and inserting a jet (for the propane). Remove the float and figure out a way to regulate the low pressure gaseous propane coming from the regulator (hi-pressure liquid to low pressure gas) to the carb propane jet. and you're good to go. you could even keep it dual fuel by leaving all the gas lines intact and minimal modification to the carb. There are plans on the internet for VW's that would give you a place to start. Honda50 has the right idea, a ball valve would work perfect. And for all the comments about how LP has lower power, that is simply not true. The reason you are getting lower power is because the engine's compression ratio is optimized for gasoline. Optimize it for propane and you get MORE power than gas. The reason for this is propane has a higher octane than gasoline. Look it up if you don't believe me. Very interesting idea by the way.
 
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