On Sun, 04 Nov 2012 13:16:34 -0800, Gunner
wrote:

On Sun, 04 Nov 2012 14:44:03 -0500, wrote:

On Sat, 03 Nov 2012 22:24:16 -0700, Gunner
wrote:


Im thinking more along the lines of a Pinto engine or similar. When
one simply changes the pulley sizes...an idling engine can spin a
genny at 1800 rpm easily. How many hp is the typical small engine out
of a Saturn or Pinto or similar?

the little 1.9l Saturn engine is 85hp out of the box. At idle...how
long will it run on 5 gallons of fuel? 10-15 hours or more?

And they can be had very very cheaply out of wrecks and other sources.
A buddy of mine built one using the HF 10kw gennhead and a Pinto
engine. It runs for days on a 20 gallon gas tank. At something like
800 rpm

Gunner


Gunner
The Saturn 1.9 is 85HP at 5000 rpm in original form, and 100HP at
5000 with multiport injection.

Torque at 2400 is 107 and 115 respectively.

Assuming 80% torque is available at 1800 RPM, the early engine would
produce [ (.8X107)X1800/5252] =29.33 Hp

The multiport engine, under the same assumption, would produce
[(.8X115)X1800/5252] = 31.53 HP

Assuming 80% of maximum rated torque on an engine without variable
valve timing is being quite generous, from my experience.

I'd call 25 and 27 HP pretty realistic.

Also, idle consumption and full load consumption at 1800 RPM have
absolutely nothing in common. Specific fuel consumption at 1800 RPM
MAY aproach 0..4 per HP Hour. That would mean ABOUT 10 lbs per hour
for the low powered engine. At 6 lbs per american gallon of regular
gasoline, we are looking at just under 1.5 gallons per hour, so about
3.3 hours at full load - of approxemately 15 KW with an average
generator head and a reasonably well set up belt drive.
At anything less than full output, the efficiency would drop quite a
bit, so half load MIGHT give you 5 hours of running.

Take off the OEM fuel injection system and replace with a custom
tuneable unit, and retime the camshaft to move the torque peak down
closer to the running speed, and you could perhaps improve efficiency
a bit and squeeze, say, 7 hours at half load out of the system.

And if its run at an idle with say...4kw load? 15kw is a hell of a
loadout. I dont pull but 2kw with just the basic...CF lights, reefer
motor, and a TV or radio, plus the blower for the gas furnace. Make
that 2.5kw on furnace startup.

Ill have to see if I can get ahold of Gene, he documented his usages
pretty well and I know he runs his homestead on that engine/genset for
about 4 days on 20 gallons of fuel. At an idle.

My genset here at the homestead is a 4kw Onan and it runs everything
nicely, including the popcorn popper (grin) on about 1/3 gallon an
hour with everything running balls to the wall. Its an 1800 rpm twin
cylinder motor out of a wrecked motorhome.

Which btw..is another good place to find gensets.

Gunner

Actually about the BEST place to get one - particularly if you want
dual fuel (propane/gasoline) Take a 12HP twin (at 3600 RPM) and run
it at 1800 RPM as a 6 HP engine on a 4Kw Generator head and it is a
long life unit - particularly with a full flow oil filter set-up.

The liquid cooled systems are significantly quieter than air cooled -
and a lot of the higher end motorhome units are moving to liquid
cooled. More expensive though.