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Small engine propane conversion

I have a Taylor Dunn cart with an Onan Elite 140 engine that wont idle. The engine and its carburetor seem to be extinct, a few places say they have a carb for 300+ dollars. This thing is destined to be used inside so a propane conversion is the way to go.

In looking for a conversion kit the ones offered for small engines seem to be designed for generators and engines that run at steady speed. The kits are mainly a vaporizer, and gas tube that attaches to the airbox. On a forklift burning propane how is load sensed and what mechanism enriches the fuel delivery? I have run the engine with a weed burner stuck in the carb but gasoline is still providing off idle enrichment. I have the room to make a manifold if needed for a propane carb if a direct fit is not possible.

Steve
 
A propane carb is just a mixer. The engine airflow (on the atmosphere side of the throttle blade) actually sucks the propane out of the vaporizer.
 
Your existing carburetor butterfly controls the engine speed, when switching to propane. The more vacuum you have, the more propane the regulator/vaporizer will provide.
 
On a forklift the gas is heated and vaporized by coolant heat.....I know air cooled engines do run on gas ,but how do you rig up heat?.....use the exhaust seems a bit extreme?
 
I looked at an Onan generator that is propane fueled, it has a loop of metal tubing inline with the feed from the gas bottle to the vaporizer. That tube is clamped to the exhaust with perhaps 30" of contact. In looking at the systems for small engines many are using gas bottles like a BBQ, are these bottles usable horizontally like a forklift bottle? I have several 40# bottles for a camper that I would like to use.

Steve
 
I have a Hesco utility company trailer with a 7.5 kw generator set up to run off of either propane or gasoline. In the front of the trailer there are two 40# propane bottles used upright, and the engine uses vapor draw. Do you know what HP you engine is- and what HP it will actually be used at?

As the rate of vapor draw propane use increases, the liquid propane evaporation cools the liquid and the bottle, with a larger bottle taking longer to cool. As the propane cools, the rare of evaporation slows. Smaller engines do well on vapor draw propane- even with #20 bottles. As the engine HP increases, the 20# cannot meet the demand, and a 40# is needed (or two 20# manifolded together). Go up further in HP, and you need to go to liquid draw.

If a propane tank is set up for vapor only, you should not turn it over to try and draw liquid.

Well- I found your answer. Look at page 9-5. No mention of liquid draw in describing the factory LP carb function.
https://f01.justanswer.com/mr2cycle...8184f4_492-4714+Onan+E125V+&+E140V+SM.pdf

Your 40 lb bottles should work out for you.
 








 
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