The question I have is if the demand unit is from a fork lift truck, is it a vapouriser. ie ment to be fed with liquid propane and water heated. If so it has both regulator stages. vapouriser, and first stage to around 100 psi, into the second stage which is a zero biased guvenor, no suction at the outlet, no flow.
Propane has 19,500 BTU per pound, so you can work out your requirement if you can borrow a gas analizer the stoichometric mixture is 14 - 17% and you can regulate the flow to the engine with a screw into the carb fitting.
Look at CAT forlifts they used a US made Beam system with lots of set up data.
Brian.[ Parent ]
The vapourizer style regulator will have no problems with vapour, the problem could come in the bottle where the liquid becomes a gas, if it can't get enough heat back into the bottle, you will get a frost line round the bottle at the liquid level. Propane boiles at minus 44 C, and expands around 700 volumes. At around 65C the tank pressure with no take off will be around 150PSI.
The carb adaptor can be a simple pipe entering the air flow anywhere above the narrow part of the choke tube, it is refered to as a spud adaptor, we used to drill through the side of the carb just below the air cleaner clamp. Some vapourizers have a solenoid on the second stage to give a gas purge to assist in cold starting. Air cooled engines had a vapourizer that was a concentric pipe that went into the exhaust.
There should be no problems with what you are trying to do and the engine life will be extended, propane is carbon deficient in its combustion so it will clean the engine, if you have trouble starting close the plug down 5 thou propane has a higher ignition temp, if the engine has points not electronic ignition it could eat the points more quickly, it has a slower flame front so there is a longer push on the piston so the bearings should last longer.
good luck
Brian [ Parent ]
This reminds me of something that's been bugging me. I had always thought running a generator on propane or natural gas would make it live longer, but when I was looking at generators to purchase earlier this year, I kept finding comments on the various websites (mostly dealers' sites, don't remember if I saw any on a vendor's site) clearly stating the opposite - that a generator run on propane or natural gas would have to be replaced sooner. In some cases, considerably sooner!
So, why would they be saying that, when it seems fairly logical that it should live longer? Or maybe I missed something - I was lumping propane/NG together, but only paying attention to NG since that's what I would have run. [ Parent ]
If the engine has high carbon valve seats it can suffer damage to the seats, and rotory engines ie Wankel require fuel lubrication of the rotor tips, and suffer excessive wear of the tips.
As several generator companies offer LPG as an alternative fuel option, and CAT do an engine that will run on diesel, petrol, or various gasses by selecting the choice of fuel from the panel, but they are 12 ltr V12 not used in many RVs.
Generator manufacturers don't normaly go for high performance engines, 900, 1500, or 3000 depending on the number of poles, sorry in the US those RPM figures will be corespondingly higher. I would have no hesitation in running a small domestic generator on LPG, add to the fact the exhaust gasses are mainly CO2 and water, the Nox products are minimal.
Hope this helps
Brian. [ Parent ]
Sounds like it might be a good idea to advance the spark a tad, too. More power and efficiency.[ Parent ]
