Lincoln Electric SAE400 WELD'N AIR, Operator'S Manual

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D-2
MAINTENANCE
D-2
COMMUTATOR AND BRUSH MAINTENANCE
Uncovered rotating equipment can be dangerous.
Use care so your hands, hair, clothing or tools do
not catch in the rotating parts. Protect yourself
from particles that may be thrown out by the rotat-
ing armature when stoning the commutator.
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The generator brushes are properly adjusted when the
welder is shipped. They require no particular attention.
DO NOT SHIFT THE BRUSHES or adjust the rocker
setting.
Shifting of the brushes may result in:
- Change in machine output
- Commutator Damage
- Excessive brush wear
Periodically inspect the commutator, slip rings and
brushes by removing the covers. DO NOT remove or
replace these covers while the machine is running.
Commutators and slip rings require little attention.
However, if they are black or appear uneven, have
them cleaned by an experienced maintenance man
using fine sandpaper or a commutator stone. Never
use emery cloth or paper for this purpose.
NOTE: If the welder is used in dirty or dusty locations,
or if the welder is not used for prolonged periods of
time, it may be necessary to clean the commutator and
slip rings more often.
Replace brushes when they wear within 1/4" of the pig-
tail. A complete set of replacement brushes should be
kept on hand. Lincoln brushes have a curved face to fit
the commutator. Have an experienced maintenance
man seat these brushes by lightly stoning the commu-
tator as the armature rotates at full speed until contact
is made across the full face of the brushes. After ston-
ing, blow out the dust with low pressure air.
To seat the slip ring brushes, position the brushes in
place. Then slide one end of a piece of fine sandpaper
between slip rings and brushes with the coarse side
against the brushes. With slight additional finger pres-
sure on top of the brushes, pull the sandpaper around
the circumference of the rings, in direction of rotation
only - until brushes seat properly. In addition, stone
slip ring with a fine stone. Brushes must be seated
100%.
Arcing or excessive exciter brush wear indicates a pos-
sible misaligned shaft. Have an authorized Field
Service Shop check and realign the shaft.
COOLING SYSTEM
The SAE400 and SAE400 WELD’N AIR are equipped
with a pressure radiator. Keep the radiator cap tight to
prevent loss of coolant. Clean and flush the cooling
system periodically to prevent clogging the passage
and overheating the engine. When antifreeze is need-
ed, always use the permanent type.
PRE FILTER / WASHER SEPARATOR
When working on the fuel system
• Keep unguarded lights away, do not
smoke !
• Do not spill fuel !
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The SAE-400 and SAE400 Weld”n Air machines with
Codes 10884 and above are equipped with a
Fuel Pre-
Filter/Water Separator Assembly located before the
lift pump mounted to the engine block.
FUEL PRE-FILTER/WATER SEPARATOR ASSEMBLY
The pre-filter is a 150 micron screen designed to pro-
tect against gross fuel contamination of the water sep-
arator element and the Secondary Fuel Filter. If the
pre-filter becomes plugged it may be removed, inspect-
ed, cleaned and reinstalled. In general this only needs
to be done with each water separator element change
(about every 1,000 hrs.) However if at any time exces-
sive fuel contamination is suspected or a sudden fall-
off in engine performance is detected the pre-filter
screen should be inspected and cleaned. Follow the
following procedure:
1. Close the fuel shutoff valve located on the fuel
strainer mounted to the under side of the fuel tank.
2. Unscrew the cap ring located on the top of the filter
header and remove the plastic center cap and O-
ring.
3. Remove the large white volume plug located direct-
ly under the center cap in the upper cavity of the fil-
ter header. Use a small screwdriver (or similar
device) to lift the plug part way out of the cavity to
assist with its removal.
Be careful not to damage the pre-filter screen with
the tool used to remove the plug.
SAE400 & SAE400 WELD ’ N AIR
WARNING
WARNING