Current Output - Mercury 225 EFI Service Manual

Current Output

NOTE: Before conducting current output test, assure that all boat electrical accessories
are turned OFF.
1. With engine shut off, install ammeter with clamp-on current probe (capable of reading
60+ amperes) onto alternator charging conductor (10 AWG Red Wire).
2. Start engine and allow to warm up.
3. Battery voltage should be between 14.2 and 15.0 VDC for all engine RPMs.
Alternator output current should correspond with graph below. Example: If engine is
revolving at 2000 RPM current meter should be approximately 14.5
a
a -
b -
c -
NOTE: Alternator amperage output can vary by as much as 10% due to heat buildup from
the numbers listed below. Alternator output listed below was with a battery loaded at 12.6
volts.
RPM
600
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
5750
90-884294 OCTOBER 2001
Ammeter (DMT 2000 Digital Tachometer Multimeter 91-854009A1)
Clamp-On Current Probe (91-802650)
Alternator Charging Conductor (10 AWG Red Wire)
AMPS @ ALTERNATOR
21
37
44
48
50
51
51
52
52
52
52
52
CHARGING & STARTING SYSTEM
c
AMPS @ BATTERY
16
31
36
39
40
41
41
42
42
42
42
42
3 Amps.
b
59066
ENGINE DRAW AMPS
5
6
8
9
10
10
10
10
10
10
10
10
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