Author Topic: New 24V gas generator project  (Read 6632 times)

0 Members and 1 Guest are viewing this topic.

Volvo farmer

  • Hero Member
  • *****
  • Posts: 1026
New 24V gas generator project
« on: October 23, 2010, 01:59:50 PM »



In my quest to charge batteries with gasoline, I came upon this little problem using a regular Outback inverter/charger. I could charge batteries, but the leftover generator power got routed into the house and looked like this






So I was l,ooking for 24V gas generators and found three of these military 24V 1500W generators on Craigslist last month. Id swapped out parts until I got one up and running! Build date on this one is 1968.




I find it amazing that the thing starts on first or second pull every time. Who needs a recoil starter?



Old school voltage regulation works perfectly. No matter where I set the voltage knob, the thing seems to settle down at about 90% load.





Meter has a little moisture in it but still works!



It's rated at 1.5KW and seems to have no problem running right at that rating for extended periods. I have only run it about 45 minutes so far but it seems happy cranking out 40-50 amps into batteries at 28-30V. There's no muffler and it will deafen you if you stand next to it for too long. I'm going to move this into the power shed and fabricate a muffler here before the days get too short. Now my inverter can continue to put a perfect sine wave into the house and I can charge batteries on dark days with gasoline.

This old military stuff was built pretty well, much easier to work on and more straightforward than many of the new generators you can buy today.  I still can't get over the fact that I can rope pull start the thing every time and it is over 40 years old!






Less bark, more wag.

ChrisOlson

  • SuperHero Member
  • ******
  • Posts: 3642
  • Country: us
Re: New 24V gas generator project
« Reply #1 on: October 23, 2010, 02:56:38 PM »
Those old military units are tough and built good.  I use a gas battery charger when power gets low too.  My system is all 12 volt and I use an old Techumseh snowblower engine driving a Delco 10SI.  It will run for about 5 hours on 2 pints of gas.


Fused

  • Guest
Re: New 24V gas generator project
« Reply #2 on: October 23, 2010, 03:59:41 PM »


I get 1420 watts out of mine, all parts collected from old non assembled projects. Cost, about 5 hrs labor. Starts first or second pull every time. PMA hardly gets warm to the touch after de tuning the alt for lower output.

Im sure that military gen is a good buy.

Fused

ChrisOlson

  • SuperHero Member
  • ******
  • Posts: 3642
  • Country: us
Re: New 24V gas generator project
« Reply #3 on: October 23, 2010, 05:28:33 PM »
I get 1420 watts out of mine, all parts collected from old non assembled projects

Mine doesn't put out that much.  About 30-35 amps with the engine running just above idle and the alternator full-fielded.  But it's enough to keep the wood furnace blower going when it's 30 below, in the middle of the night, and the wind hasn't blown or the sun shine for three days.

That little Delco 10SI won't take much more than that anyway without burning the stator out of it.  If I open the throttle on the engine it will put out 50 amps but then the stator burns out after about 15 minutes.

I think those military units like VF got have a brush-type DC generator in them, and those are pretty robust.
--
Chris

Fused

  • Guest
Re: New 24V gas generator project
« Reply #4 on: October 23, 2010, 06:03:43 PM »
My delco 10si is a PMA.

28.4v batteries I can push 50a. Just above idle puts out 15a. 50a will warm it up good but for normal use around 15a it runs quite cool.

I rarely need mine, but I set it up so I can rig it for DC welding. Kinda portable too.

Fused

ChrisOlson

  • SuperHero Member
  • ******
  • Posts: 3642
  • Country: us
Re: New 24V gas generator project
« Reply #5 on: October 23, 2010, 06:22:34 PM »
I rarely need mine, but I set it up so I can rig it for DC welding. Kinda portable too.

Mine just sits outside the back of the house by the turbine tower with a box over it and I leave the generator cord running from the battery bank hooked up to it all the time.  It's not that heavy, so I can pick it up and carry it in the house to warm up a bit if it won't start.  Usually, though, it'll start at 30 below with 10W-30 oil in it if I pull the starter rope thru real slow 5-10 revolutions to free it up a bit

I just use a 10 AWG cord to it and I used to have a standard outlet on it like shown in the photo.  But I burned that outlet up because it was only rated at 20 amps.  I replaced that outlet with a 50 amp clothes dryer plug and that one seems to hold.
--
Chris

ghurd

  • Super Hero Member Plus
  • *******
  • Posts: 8059
Re: New 24V gas generator project
« Reply #6 on: October 24, 2010, 01:39:40 AM »
VF,
Is that 2 spark plug wires I see?
G-
www.ghurd.info<<<-----Information on my Controller

Volvo farmer

  • Hero Member
  • *****
  • Posts: 1026
Re: New 24V gas generator project
« Reply #7 on: October 24, 2010, 08:45:12 AM »
Yeah, it's an old Continental engine I believe. 3600 RPM, 16 cu in. and rated (conservatively) at about 3HP.  Uses a diaphragm type fuel pump, and I think there's points in there somewhere too.  Those bumps on top of the engine cover the tops of the valves, and the lash number is stamped right into the covers.

I got all three generators for $75. Someone took the plugs out of one and left it in the weather so it's seized. The other was an '86 vintage and ran for an hour before the ignition system quit. It had some kind of electronic ignition on it so I abandoned it and got this one going. 

I figured even if I didn't get one running that there was $75 worth of fun in trying!
Less bark, more wag.

ChrisOlson

  • SuperHero Member
  • ******
  • Posts: 3642
  • Country: us
Re: New 24V gas generator project
« Reply #8 on: October 24, 2010, 09:36:45 AM »
Yeah, it's an old Continental engine I believe. 3600 RPM, 16 cu in. and rated (conservatively) at about 3HP.

Yeah, it looks like a Teledyne aircraft ground power unit.

How is it on fuel?  Can you idle it down and still get the voltage you need, or does it have to run flat out all the time?

One note about those old OHV Continental engines - they were made for leaded gas and the valve guides go to hell in short order on today's pump gas.  If you're going to run it a lot it probably wouldn't hurt to run to the local airport and get some 100LL avgas and it'll be much happier.
--
Chris

Bruce S

  • Global Moderator
  • Super Hero Member Plus
  • *****
  • Posts: 5413
  • Country: us
  • USA
Re: New 24V gas generator project
« Reply #9 on: October 25, 2010, 11:50:37 AM »
VF;
 good ole OD green :). Watch those two condensers inside the control area if you start getting surges or what we used to call voltage hunting, those will be dried up.
After sitting the dry out and fail.

The electronic 86er, they went to IR much like what Magnalite came up with to replace point/condensers. Normally when they don't work it's the pickup on the rotor, they wear out. You can replace, but may be out of luck finding. OLD small engine repair shop will be able to cross-match, but might have to go to point type setup.

BTW: old ARMY trick to un-seize engine was to pour fresh Automatic tranny oil in try to turn and let sit a day of two then keep turning by hand until unseized.
Rings will be toast tho.
Compression is up there on old one and was originally built to run off anything gasoline related. The spark wires should be weather proof too.

NICE find even if only one stays working.

Bruce S
A kind word often goes unsaid BUT never goes unheard

DanG

  • Hero Member
  • *****
  • Posts: 1122
  • Country: us
  • 35 miles east of Lake Okeechobee
Re: New 24V gas generator project
« Reply #10 on: October 25, 2010, 12:04:55 PM »
I had a late 1940's two-stroke Army Radio Corps 120VAC generator that used the fuel-air intake plenum to cool the over sized main bearing - if it had been a 4-stroke I'd still have it...