Try Cranking The Engine; Test Primer Switch - Guardian 4700 Repair Manual

Section 7
DIAGNOSTIC TESTS
other test lead to Stator Lead Wire No. 55. Normal Battery
Charge Winding resistance should be measured.
3. Connect one test lead to Stator Lead Wire No. 77. Connect the
other test lead to Stator Lead Wire No. 55. Normal Battery
Charge Winding resistance should be measured.
4. Connect one test lead to Stator Lead Wire No. 55. Connect the
other test lead to Stator Leads Wire No. 11 & 33 at the back of
CB1. "Infinity" should be measured.
5. Connect one test lead to Stator Lead Wire No. 55. Disconnect
Stator Lead Wire No. 2 from the DPE circuit breaker (CB3) and
connect the other test lead to Wire No. 2. "Infinity" should be
measured.
6 Connect one test lead to Stator Lead Wire No. 55. Connect the
other test lead to frame ground. "Infinity" should be measured.
7. Connect one test lead to the Battery Charge Resistor terminal
that Wire No. 55 was removed from. Connect the other test
lead to frame ground. One (1) ohm should be measured. If 1
ohm was not measured, remove Wire No. 0 from the Battery
Charge Resistor. Connect one test lead to Wire No. 0 and the
other test lead to frame ground. Continuity should be mea-
sured. Repair or replace Wire No. 0 if defective and retest the
Battery Charge Resistor.
BATTERY CHARGE WINDING RESISTANCE:
0.140 - 0.174
RESULTS:
1. For Steps 2 & 3, keep in mind that the resistance values are
very low. Depending upon the quality of the VOM, it may read
continuity across these winding. Exercise good judgement with
these values.
2. If Steps 2, 3, 4, 5 & 6 fail any test, replace the Stator.
3. In Step 7, if Wire No. 0 reads continuity, but resistor does not
measure 1 ohm, replace the Battery Charge Resistor.
4. If all of the Steps in this test pass, perform "Insulation
Resistance Test" on page 11.
TEST 18 - TRY CRANKING THE ENGINE
DISCUSSION:
If the Fuel Primer Switch on the generator panel is
actuated, but the Fuel Pump does not run (priming
function doesn't work), perhaps battery voltage is not
available.
PROCEDURE:
Hold the Start-Stop Switch at "START". The engine
should crank and start.
Page 38
Ω
RESULTS:
1. If the engine cranks normally, but the priming function still
doesn't work, go to Test 19.
2. If engine will not crank, go to Test 21. Refer to Problem 6 of
Section 6.
3. If engine cranks but won't start, go to Problem 7 of Section 6.
4. If engine starts hard and runs rough, go to Problem 8 of
Section 6.
TEST 19- TEST PRIMER SWITCH
DISCUSSION:
A defective primer switch can prevent the priming
function from occurring.
Switch failure can also prevent the engine from start-
ing, since the switch is in series with the Wire14 circuit.
(Also see "Fuel Primer Switch," page 19).
Figure 7-11. – Primer Switch
PROCEDURE:
1. Set a VOM to read battery voltage (12 VDC).
2. Connect the positive (+) meter test lead to the Wire 15 terminal
of the Primer Switch, the negative (-) meter test lead to frame
ground. The meter should indicate battery voltage.
3. Connect the positive (+) meter test lead to the Wire 14A termi-
nal of the Primer Switch, the negative (-) meter test lead to
frame ground.
a. With the Primer Switch NOT actuated, no
voltage should be indicated.
b. Actuate the switch to its "PRIME" position
and the meter should read battery voltage.
4. Repeat Step 3. Disconnect connector 2 at the Fuel Pump.
Connect VOM positive (+) test lead to Wire 14A, (Pin 2 of
Connector 2) going up to the Control Panel (see Figure 7-12).
14
14A
15