1999 YAMAHA YZF-R7 air filter

ENG

4 - 4
ENGINE
Order Job/Part Q’ty Remarks
Disconnecting the leads and hoses
Disconnect the parts in the order listed.
Fuel tank and air filter case cover Refer to “FUEL TANK AND AIR FILTER
COVER” in chapter 3.
Air filter case and throttle body
assemblyRefer to “ELECTRONIC FUEL INJEC-
TION” in chapter 6.
Engine oil and oil filter cartridge Drain.
Refer to “CHANGING THE ENGINE
OIL” in chapter 3.
Oil cooler and thermostat assembly Refer to “OIL COOLER” and “THER-
MOSTAT ASSEMBLY” in chapter 5.
1 Battery negative lead 1
2 Battery positive lead 1
ACHTUNG:CAUTION:
First, disconnect the negative lead,
then the positive lead.

5 - 3
COOL

EB502000
RADIATOR AND THERMOSTAT
Order Job/Part Q’ty Remarks
Removing the thermostat assembly
Remove the parts in the order listed.
Rider seat and fuel tank Refer to “SEATS” and “FUEL TANK” in
chapter 3.
Air filter case and rubber cover Refer to “AIR FILTER CASE AND IGNI-
TION COIL PLATE” in chapter 3.
Carburetor assembly Refer to “CARBURETORS” in chapter 6.
Coolant Drain.
Refer to “CHANGING THE COOLANT”
in chapter 3.
Fuel tank and air filter case cover Refer to “FUEL TANK AND AIR FIL-
TER” in chapter 3.
Air filter case Refer to “ELECTRONIC FUEL INJEC-
TION” in chapter 6.
1 Thermostat assembly 1
2 Thermostat assembly inlet hose 1
RADIATOR AND THERMOSTAT

6 - 1
EFI

ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
Order Job/Part Q’ty Remarks
Removing the injector 2 assembly
and air filter case
Remove the parts in the order listed.
Air filter case cover Refer to “FUEL TANK AND AIR FIL-
TER” in chapter 3.
1 Crankcase breather hose 1 Disconnect.
2 Fuel hose 3
3 Injector 2 sub-lead coupler 3 Disconnect.
4 Pressure sensor hose 2 Disconnect.
5 Plastic band 1
6 Injector 2 assembly 1
7 Spacer 6
8 Air funnel 4
9 Air funnel bracket 4
10 Fuel hose joint pipe 1
6

6 - 2
EFI

ELECTRONIC FUEL INJECTION
Order Job/Part Q’ty Remarks
11 Intake air temperature sensor 1
12 Copper washer 1
13 Air filter case breather hose 1 Disconnect.
14 Negative pressure hose 1 Disconnect.
15 Air funnel rubber seat 4
16 Air filter case 1
For installation, reverse the removal
procedure.
6

6 - 14
EFIELECTRONIC FUEL INJECTION
CHECKING THE FUEL PUMP AND
PRESSURE REGULATOR OPERATION
1. Check:
• pressure regulator operation
t t t t t t t t t t t t t t t t t t t t t t t t t t t
a. Remove the fuel tank and air filter
case cover.
Refer to “FUEL TANK AND AIR FIL-
TER” in chapter 3.
b. Disconnect the nagative pressure
hose 1 from the pressure regulator
at the joint.
c. Disconnect the injector fuel pipe 3 2
from the fuel distributor.
d. Connect the mity vac 3 onto the neg-
ative pressure hose from the pressure
regulator.
e. Install the pressure gauge 4 and
adapter 5 with the washers and
injector fuel pipe 3 onto the fuel dis-
tributor.
f. Install the fuel tank.
Refer to “FUEL TANK AND AIR FIL-
TER” in chapter 3.
g. Start the engine.
h. Measure the fuel pressure.
Mity vac
90890-06756
Pressure gauge
90890-03153
Adapter
90890-03151
T R..
Adapter
30 Nm (3.0 m • kg, 22 ft • lb)
Fuel pressure
250 ~ 260 kPa
(2.5 ~ 2.6 kgf/cm
2,
35.6 ~ 37.0 psi)

8 - 9
–+ELECIGNITION SYSTEM
BAD
NOTE:
• Before troubleshooting, remove the following part(-s):
1) fuel tank
2) air filter case
3) bottom cowling
4) front cowling
5) rear cowling
• Troubleshoot with the following special tool(-s).
Replace the ECU.
Ignition checker
90890-06754
Pocket tester
90890-03112
MEASURING THE IGNITION SPARK GAP
The following procedure applies to all of
the spark plugs.
• Disconnect the ignition coil from the spark
plug.
• Connect the ignition checker 1 as shown.
2 Ignition coil
• Set the main switch to “ON”.
• Measure the ignition spark gap a.
• Crank the engine by pushing the start
switch and gradually increase the spark
gap until a misfire occurs.
• Is there a spark and is the spark gap
within specification?
Yes ® Good.
No ® Measure the ignition coil resistance.
Minimum ignition spark gap
6 mm (0.24 in)

8 - 14
–+ELECELECTRIC STARTING SYSTEM
NOTE:
• Before troubleshooting, remove the following part(-s):
1) fuel tank4) bottom cowling
2) air filter case5) front cowling
3) throttle body assembly6) rear cowling
• Troubleshoot with the following special tool(-s).
Pocket tester
90890-03112
CHECKING THE RELAY UNIT
• Disconnect the relay unit from the cou-
pler.
• Connect the pocket tester (W ´ 1) and bat-
tery (12 V) to the relay unit terminals as
shown.
• Does the starting circuit cutoff relay have
continuity between blue/white and black?
• Connect the pocket tester (W ´ 1) to the
relay unit terminals as shown.
• Check the relay unit for continuity as fol-
lows.
NOTE:
When you switch the tester’s positive and
negative probes, the readings in the above
chart will be reversed.
• Are the tester readings correct?
Yes ® Good.
No ® Replace. Battery positive terminal ® red/black 1
Battery negative terminal ®
black/yellow 2
Tester positive probe ® blue/white 3
Tester negative probe ® black 4
Tester positive probe ®
sky blue 5
Tester negative probe ®
black/yellow 2
Continu-
ity
Tester positive probe ®
sky blue 5
Tester negative probe ®
blue/yellow 6
Tester positive probe ®
black/yellow 2
Tester negative probe ®
sky blue 5
No conti-
nuity
Tester positive probe ®
blue/yellow 6
Tester negative probe ®
sky blue 5
R/B L/WW G
Lg
L/R L/BSbB/Y B B/R L/Y
6
1
3 54 2