Section 6
DIAGNOSTIC TESTS
Figure 6-32. – Tachometer
Test Bracket:
A starter motor test bracket may be made as shown in Figure
|
| METAL STOCK |
|
| 1/4" THICK STEEL |
0.5" | 2.625" |
|
|
| |
|
| 3.5" |
| 1.0" | 4" |
| 12" |
|
DRILL TWO HOLES — 1/2" |
| |
FOR STARTER |
| 2" |
MOUNTING BRACKET |
| |
|
| |
|
| DRILL TWO HOLES — 1/2" |
|
| FOR MOUNTING TACHOMETER |
|
| TAP FOR |
Figure 6-33. – Test Bracket Dimensions
Remove Starter Motor:
It is recommended that the Starter Motor be removed from the engine when testing Starter Motor perfor- mance. Assemble starter to test bracket and clamp test bracket in vise (Figure
Testing Starter Motor:
1.A fully charged 12 volt battery is required.
2.Connect jumper cables and
3.With the Starter Motor activated (jump the terminal on the Starter Contactor to battery voltage), note the reading on the
| CLAMP ON |
STARTER | AMP METER |
| |
CONTACTOR |
|
STARTER |
|
MOTOR |
|
TACHOMETER |
|
VISE | 12 VOLT |
BATTERY |
Figure 6-34 – Testing Starter Motor Performance
Note: Take the reading after the ammeter and tachometer are stabilized, approximately
4.A starter motor in good condition will be within the following specifications:
Minimum rpm | 4500 |
Maximum Amps | 50 |
Note: Nominal amp draw of starter in generator is 60 amps.
TEST 26 - Test Starter Contactor
Relay (SCR)
PROCEDURE:
1.Set voltmeter to measure DC voltage.
2.Remove Wire 15 from the Starter Contactor Relay (SCR). Connect the positive meter test lead to Wire 15 previous- ly removed. Connect the negative meter test lead to frame Ground. 12 VDC should be measured. Reconnect Wire 15 to the SCR. If 12 VDC is NOT measured on Wire 15 Stop Testing and repair or replace Wire 15 between the Fuse (F1) and the SCR.
3.Remove Wire 13 from the Starter Contactor Relay (SCR). Connect the positive meter test lead to Wire 13 previous- ly removed. Connect the negative meter test lead to frame
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