
SEBU8088-06 69
Maintenance Section
Maintenance Recommendations
•
The internal pr
essures of the high pressure fuel
lines are higher than other types of fuel system.
Before any ser
vice or repair is performed on the
engine fuel lines, perform the following tasks:
1. Stop the engin
e.
2. Wait for ten minutes.
Do not loosen the high pressure fuel lines in order to
remove air pressure from the fuel system.
Engine Oil
To relieve pressure from the lubricating system, turn
off the engine.
i03091592
Welding on Engines w it h
Electron ic Controls
SMCS Code: 1000
NOTICE
Because the strength of the frame may decrease,
some manufacturers do not recommend welding onto
a chassis frame or rail. Consult the OEM of the equip-
ment or your Caterpillar dealer regarding welding on
achassisframeorrail.
Proper welding procedures are necessary in order
to avoid damage to the engine’s ECM, sensors,
and associated components. When possible,
remove the component from the unit and then
weld the component. If removal of the component
is not possible, the following procedure must be
followed when you weld on a unit that is equipped
with a Caterpillar Electronic Engine. The following
procedure is considered to be the safest procedure to
weld on a component. This procedure should provide
a minimum risk of damage to electronic components.
NOTICE
Do not ground the welder to electrical components
such as the ECM or sensors. Improper grounding can
cause damage to the drive train bearings, hydraulic
components, electrical components, and other com-
ponents.
Clamp the ground cable from the welder to the com-
ponent that will be welded. Place the clamp as close
as possible to the weld. This will help reduce the pos-
sibility of damage.
Note: Perform the welding in areas that are free from
explosive hazards.
1. Stop the engine
. Turn the switched power to the
OFF position.
2. Disconnect th
e negative battery cable from the
battery. If a battery disconnect switch is provided,
open the switch.
3. Disconnect the J1/P1 and J2/P2 connectors from
the ECM. Move the harness to a position that will
not allow the
harness to accidentally move back
and make contact with any of the ECM pins.
g01075639
Illustration 52
Use the e
xample above. The current flow from the welder to
the grou
nd clamp of the welder will not c ause damage to any
associa
ted components.
(1) Engine
(2) Welding electrode
(3) Keysw itch in the OF F position
(4) Battery disconnect switch in the open position
(5) Disconnected battery cables
(6) Battery
(7) Electrical/Electronic com ponent
(8) Minim um distance between the compo nent that is being welded
and any electrical/electronic component
(9) The component that is being welded
(10) Current path of the welder
(11) Ground c lamp for the welder
4. Connect the welding ground cable directly to the
part that will be welded. Place the ground cable as
close as po
ssible to the weld in order to reduce the
possibility of welding current damage to bearings,
hydraulic components, electrical components, and
ground st
raps.