Day Brown wrote in a message to Jim Dunmyer:
 DB> I didn't see the beginning of this thread, but... 
I was wondering when you were gonna show up in here...   
 DB> One of the things I lost when my house burned was a homemade
 DB> LPG...
 DB> Took an old gas engine; 2-3hp is best, 5 is too hard... which 
 DB> was hooked up to an old DELCO truck generator (NOT alternator) 
Why not?  I had the thought a while back that if you tapped into an 
alternator before the diodes,  and fed the resulting AC into a transformer 
hooked up "backwards" from the usual way,  you could easily get line voltage 
AC out of it.  (Never mind,  you explain it below...)
 DB> with an 8" pulley on the engine with the standard 2-3 inch 
 DB> V-belt pulley on the generator. 
 DB> I disconnected the gas tank and gasline, and drilled a ¬" hole 
 DB> in  the air filter through which I fed a copper tubing LPG line 
 DB> right  into the throat of the carb, past the choke, which is 
 DB> disabled.
 DB> I put a 10 ohm ceramic 10 watt resistor between the A)rmature 
 DB> post and the F)ield post.  With some old generators you would 
 DB> put the resistor between the F)ld and Ground since it was 
 DB> already tapped inside the case with the Armature windings. You 
 DB> can test the setup before with a pair of jumper cables.  The 
 DB> resistor is needed to keep the field windings from frying in 
 DB> continuous use. IF you got it set up right, the generator will 
 DB> "motor" at a good clip. You may havta reduce the field resistor 
 DB> to around 3 ohms on some units.
 DB> Bolt both the motor and the generator to a 2X10; apply 12 VDC 
 DB> to the A) or (+) and metal frame (grnd) and with the 3:1 v-belt 
 DB> ratio,  the generator will turn the motor over fast enough to 
 DB> start it on LPG, which you must turn on with a gas (heater 
 DB> type) valve. crank it out till it puts out around 15 amps and 
 DB> let her run a while. A lot of old generators will do 20 amps 
 DB> all day w/o overheating.  I  know you see alternators listed at 
 DB> 80 or 100 amps, but what they do not tell you is that they will 
 DB> only do the rated output for a few minutes.. ;)  and- their 
 DB> bearings will blow if you try 25 amps for a few hours. 
Ah...!  Ok!  Maybe some truck parts?  
 DB> As you crack the gas valve, you'll be able to provide more than 
 DB> a cold motor needs, (choke condition) and it should start right 
 DB> up.  it is a bear to start on LPG with a pull rope cause it 
 DB> floods out if you don't crank fast enough. But with the 
 DB> generator doing the cranking, you can back off on the gas valve 
 DB> till it pops off. A 5hp motor is too heavy a load for most 
 DB> generators to crank, but if you can yank the rope, most 
 DB> generators can keep it cranking to start.   The LPG burns so 
 DB> clean, the motor oil stays light for months, but change it once 
 DB> or twice a year anyway; some moisture condenses in the crank 
 DB> and forms acids that eat at aluminum parts. 
 DB>  
 DB> Even if you can get an alternator hookup to start, you may see, 
 DB> as I have, that if the belt starts slapping it will tear up the 
 DB> bearings in short order, whereas the lubrilite bushings used in 
 DB> generators can take that kind of abuse till you get a round 
 DB> tuit.
 DB>  
 DB> I never got around to installing the 12vdc LPG control valve
 DB> I got for 6$, which wouldda let me turn it off remotely. 
 DB> Recently I've seen some solid state 20 amp relays that were 
 DB> designed for computer power supplies which should work as well 
 DB> as a voltage regulator to turn off the power should you run 
 DB> outta gas, and which, unlike the mechanical voltage regulators, 
 DB> don't have points to burn out.  Two hundred bucks will get you 
 DB> 240 watts of backup power; compare that to the cost of PV and 
 DB> batteries to take you through the rare times when you get 7 
 DB> consecutive days of cloudy...
Interesting stuff!  I'm going to have to see what I can come up with in 
regard to this...
email: roy.j.tellason%tanstaaf@frackit.com 
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