Guardian Technologies 4270 manual 16. - Clamp-On Ammeter, 17. - Tachometer, 18. - Test Bracket

Section 7

DIAGNOSTIC TESTS

Figure 7-16. – Clamp-On Ammeter

TACHOMETER:

A tachometer is available from your Generac Power Systems source of supply. Order as P/N 042223. The tachometer measures from 800 to 50,000 RPM (see Figure 7-17).

Figure 7-17. – Tachometer

2"

3.5"

1.75

3.5"

4"

2"

1.5"

15"

3"

Figure 7-18. – Test Bracket

TEST BRACKET:

A starter motor test bracket may be made as shown in Figure 7-18.

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 7-19).

TESTING STARTER MOTOR:

1.A fully charged 12 VDC battery is required.

2.Connect jumper cables and clamp-on ammeter as shown in Figure 7-19.

3.With the Starter Motor activated (jump the terminal on the Starter Contactor to battery voltage), note the reading on the clamp-on ammeter and on the tachometer (rpm).

Note: Take the reading after the ammeter and tachometer are stabilized, approximately 2-4 seconds.

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.

	CLAMP ON
STARTER	AMP METER
CONTACTOR
STARTER
MOTOR
TACHOMETER
VISE	12 VOLT
	BATTERY

Figure 7-19. – Testing Starter Motor Performance

Page 50