Winco PSS25000/A - Manual (Page 8)

PAGE 6 60706-171 5076-10
Natural Gas
1 3 4
UNIT OFF LINE PSI 7-11 in 7-11 in
4-6 oz. 4-6 oz.
STARTING LINE PSI 7-11 in 7-11 in
4-6 oz. 4-6 oz.
NO LOAD LINE PSI 7-11 in 7-11 in
4-6 oz. 4-6 oz.
FULL LOAD LINE PSI 7-11 in 7-11 in
4-6 oz. 4-6 oz.
LP LIQUID WITHDRAWAL
The following is a block diagram of a typical L/P Liquid
Withdrawal fuel system for the PSS25000.
Tank Fuel Solenoid Converter Engine
1 2 3 4
Reference number 1 is the fuel tank. No regulator is
required but the tank must have a liquid withdrawal drop
tube installed in it and a liquid valve on the tank.
Reference numbers 2 through 4 are installed on the
engine generator set.
Liquid fuel is delivered from the tank directly to the fuel
solenoid on the generator at full tank pressure. This
system requires no pressure regulator be installed any
where in the system. The converter mounted on the
engine generator set will take the liquid fuel at tank
pressure and convert it to vapor at the proper delivery
rate.
LP/NG FUEL ADJUSTMENTS
**** CAUTION ****
Do not make any fuel adjustments or governor adjust-
ments until all pressure readings are in compliance with
specification. See fuel pressure charts (tables 1, 2, and
3).
NATURAL GAS (NG)
Due to variations in NG fuel characteristics and BTU
levels throughout the country, it may be necessary to
readjust the fuel mixture once the engine has been
installed and serviced.
**** CAUTION ****
Never make a fuel mixture adjustment on a unit when it is
stopped or running no load. A mixture adjustment is only
effective when the engine is operating under load.
ADJUSTMENT PROCEDURE
1. Insure the unit is operating with an 80 to 100% load
or at the highest anticipated load.
Note: The mixture adjustment is located on the carbure-
tor just behind the fuel inlet hose. This mixture
adjustment is a partial turn, lean to rich, load block.
2. Begin making a mixture adjustment. Adjustments
should be made very slowly. Adjust back and forth until
the engine is running as smooth as possible.
3. The PSS25000 is equipped with an electronic
governor which requires no speed adjustment.
FUEL TYPE CONVERSION
If it should be necessary to change the type of fuel used
after a unit is received, the following procedures are
provided.
NATURAL GAS TO PROPANE
1. Turn off fuel supply.
2. Remove the fuel line from the carburetor at the
demand regulator.
3. Remove the cap on the upright column of the
regulator. This will expose the pressure spring adjusting
screw. Back off the spring adjusting screw so there is just
enough room to replace the cover. Replace the cover.
4. Invert the regulator so it is positioned with the column
pointing down.
5. Reconnect the fuel line at the regulator.
6. Remove the 1/8 NPT plug (the one closest to fuel
solenoid) located on what is now the top of the regulator.
Connect a fuel pressure meter or a manometer where
the plug has been removed. Move the generator control
switch to the run position. As the unit starts to crank the
fuel solenoid will open and you should get a pressure
reading of between 4 to 6 ounces (7 to 11 inches of water
column).
7. If the pressure is correct, remove the meter and
reinstall the pipe plug.
8. You are now ready to make the final fuel mixture
adjustment. Refer to adjustment section in this manual.
PROPANE TO NATURAL GAS
1. Turn off fuel supply.
2. Remove the fuel line from the carburetor at the
demand regulator.
3. Invert the regulator so the column is in the upright
position. Remove the cap on the upright column of the
regulator. This will expose the pressure spring adjusting
screw. Turn the screw all the way out (CCW) and then
back in (CW) about 8 turns. The plug should be approxi-
mately half way down for initial starting.
4. Reconnect the fuel line at the regulator.
5. Remove the 1/8 NPT plug (the one closest to fuel
solenoid) located on what is now the bottom of the
regulator. Connect a fuel pressure meter or a manometer
where the plug has been removed. Move the generator
control switch to the run position. As the unit starts to
crank the fuel solenoid will open and you should get a
pressure reading of between 4 to 6 ounces (7 to 11
inches of water column).