Generac Power Systems 941-2 Service Manual page 125

If the engine cranks but won't start, it is possible that
a failure in the circuit board has occurred and DC
power is not being delivered to the Wire 14 circuit.
This test will determine if circuit board action will deliver
battery voltage to the necessary engine components.
PROCEDURE:
Set a VOM to read battery voltage. Connect the meter
test leads across Pin J2-9 of the A6060 circuit board
and Pin J2-6 of the circuit board connector (to which
common ground Wire 0 connects). Crank the engine
and the meter should read battery voltage.
RESULTS:
1. If DC voltage was NOT indicated in Test 17, but IS indicated
now, repair, reconnect or replace Wire 14 between board and
Ignition Module.
2. If no DC voltage in Test 3 but good voltage now, replace Wire
14 between board and fuel pump.
3. If there is no DC output from the circuit board to Wire 14,
replace the A6060 circuit board.
Figure 10. Receptacle J2
TEST 22-TEST AUTOMATIC CHOKE
DISCUSSION:
Refer to Section 3.5, "AUTOMATIC CHOKE".
TEST PROCEDURE:
See Section 3.5.
RESULTS:
1. Adjust or repair choke system as necessary.
2. !f choke is good, go to Test 23.
ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING
DISCUSSION:
If the engine won't start or if it starts hard and runs
rough, one possible cause of the problem is carburetion.
PROCEDURE:
Before making a carburetion check, make sure the
fuel tank has an ample supply of clean fresh gasoline
(gasoline fuel systems) or gaseous fuel. The installer
may have installed a gas or gasoline shutoff valve in
the fuel supply system. Make sure all shutoff valves
are open.
Make sure the automatic choke is working properly
and that the choke closes completely.
If the engine will not start, remove the spark plug and
inspect it. If the plug is WET, look for the following:
• Overchoking.
• Water in fuel.
• Excessively rich fuel mixture.
• Intake valve stuck open.
If the spark plug is DRY, look for the following:
• Carburetor gasket(s) leaking.
• Fuel line plugged or shutoff valve not opening.
• Intake valve stuck closed.
• Inoperative fuel pump.
• Clogged fuel filter.
RESULTS:
Adjust or repair carburetor or fuel system as necessary.
DISCUSSION:
An engine that will not start or one that starts hard
and runs rough may be caused by a failure in the
engine's mechanical system.
PROCEDURE:
The first step in checking for an engine problem is to
perform a compression check. To check engine com-
pression, proceed as follows:
1. Remove the spark plug.
2. Insert an automotive type compression gauge into the spark
plug hole.
3. Crank the engine until there is no further in-crease in pressure.
The highest reading obtained is the engine's compression
pressure.
TEST 23- CHECK CARBURETION
TEST 24- CHECK ENGINE
Section 7.2
(continued)
Page 7.2-15