Gast 74R Operation & Maintenance Manual Download Page 3

OPERATION

Injury Hazard

Install proper safety guards as needed.

Keep fingers and objects away from openings and
rotating parts.

When provided, motor terminal covers must be in
place for safe operation.

Product surfaces become very hot during operation,
allow product surfaces to cool before handling.

Air stream from product may contain solid or liquid
material that can result in eye or skin damage,
wear proper eye protection.

Wear hearing protection. Sound level from motor
may exceed 70 dBA.

Failure to follow these instructions can result in
burns, eye injury or other serious injury.

WARNING

Model with a power supply cord:
This product must be grounded.  For either 120-volt or
220/240-volt circuits connect power supply cord
grounding plug to a matching grounded outlet.  Do not
use an adapter.  (See above diagram.)

Check with a qualified electrician or serviceman if
the grounding instructions are not completely
understood, or if you are not sure whether the
product is properly grounded.  Do not modify the
plug provided.  If it will not fit the outlet, have the
proper outlet installed by a qualified electrician.

In the event of an electrical short circuit, grounding
reduces the risk of electric shock by providing an
escape wire for the electric current.  This product may
be equipped with a power supply cord having a
grounding wire with an appropriate grounding plug.
The plug must be plugged into an outlet that is properly
installed and grounded in accordance with all local
codes and ordinances.

Grounded Plug

Grounding Pin

Grounded Outlet

120-volt grounded connectors
shown.  220/240-volt grounded
connectors will differ in shape.

Model that is permanently wired:
This product must be connected to a grounded,
metallic, permanent wiring system, or an equipment
grounding terminal or lead on the product.

Power supply wiring must conform to all required safety
codes and be installed by a qualified person.  Check
that supply voltage agrees with that listed on product
nameplate.

Extension cords:
Use only a 3-wire extension cord that has a 3-blade
grounding plug.  Connect extension cord plug to a
matching 3-slot receptacle.  Do not use an adapter.
Make sure your extension cord is in good condition.
Check that the gage wire of the extension cord is the
correct size wire to carry the current this product will
draw.

An undersized cord is a potential fire hazard, and will
cause a drop in line voltage resulting in loss of power
causing the product to overheat.  The following table
indicates the correct size cord for length required and
the ampere rating listed on the product nameplate.  If in
doubt, use the next heavier gage cord.  The smaller
the gage number, the heavier the wire gage.

Minimum gage for extension cords

Amps

Volts

Length of cord in feet

120v

25

50

100

150

200

250

300

400

500  

240v

50

100

200

300

400

500

600

800

1000

0-2

18

18

18

16

16

14

14

12

12

2-3

18

18

16

14

14

12

12

10

10

3-4

18

18

16

14

12

12

10

10

8

4-5

18

18

14

12

12

10

10

8

8

5-6

18

16

14

12

10

10

8

8

8

6-8

18

16

12

10

10

8

6

6

6

8-10

18

14

12

10

8

8

6

6

4

10-12

16

14

10

8

8

6

6

4

4

12-14

16

12

10

8

6

6

6

4

2

14-16

16

12

10

8

6

6

4

4

2

16-18

14

12

8

8

6

4

4

2

2

18-20

14

12

8

6

6

4

4

2

2

Start Up
If motor fails to start or slows down significantly under
load, shut off and disconnect from power supply.  Check
that the voltage is correct for motor and that motor is
turning in the proper direction.  Check the plug, cord
and switch for damage.  If so equipped, the thermal
protection switch has tripped, the motor can restart after
cooling.

It is your responsibility to operate this product at
recommended pressures or vacuum duties and
room ambient temperatures.  Do not start against a
vacuum or pressure load.

Summary of Contents for 74R

Page 1: ...must be filtered out Consult your Gast Distributor Representative before using at high altitudes This pump is oil less and requires NO lubrication IMPORTANT PLEASE READ THIS MANUAL AND SAVE FOR FUTURE REFERENCE Thank you for purchasing this Gast product It is manufactured to the highest standards using quality materials Please follow all recommended maintenance operational and safety instructions ...

Page 2: ...any way can cause the product to overheat Mounting This product can be installed in any orientation Mounting the product to a stable rigid operating surface and using shock mounts will reduce noise and vibration INSTALLATION Accessories The product s external intake and exhaust muffler will provide adequate filtration in most applications Check filters periodically and replace when necessary Consu...

Page 3: ...em or an equipment grounding terminal or lead on the product Power supply wiring must conform to all required safety codes and be installed by a qualified person Check that supply voltage agrees with that listed on product nameplate Extension cords Use only a 3 wire extension cord that has a 3 blade grounding plug Connect extension cord plug to a matching 3 slot receptacle Do not use an adapter Ma...

Page 4: ...ollow proper shutdown procedures to prevent product damage NEVER ADD OIL TO THIS OIL LESS PUMP Proper shutdown procedures must be followed to prevent pump damage Failure to do so may result in premature pump failure Gast Manufacturing Rocking Piston Oil Less Pumps are constructed of ferrous metals or aluminum which are subject to rust and corrosion when pumping condensable vapors such as water Fol...

Page 5: ...responsible for freight charges both to and from Gast in all cases This warranty does not apply to electric motors electrical controls and gasoline engines not supplied by Gast Gast s warranties also do not extend to any goods or parts which have been subjected to misuse lack of maintenance neglect damage by accident or transit damage THIS EXPRESS WARRANTY EXCLUDES ALL OTHER WARRANTIES OR REPRESEN...

Page 6: ...1 AP119 AT275 12 RETAINER SCREWS 2 AT283 AT283 13 RETAINER PLATE 1 AT715 AT566A 14 PISTON CUP 1 AT329 AT280 15 FAN 1 AP108A AP108A 16 GRILLE SHROUD 1 AP107A AP107A 17 VALVE PLATE ASSEMBLY 1 AP102A AP102A 18 FILTER 1 B300A B300A SERVICE KIT 1 K806 K806 EXPLODED PRODUCT VIEW PARTS ORDERING INFORMATION 74R shown Item not shown Denotes parts included in the Service Kit Parts listed are for stock model...

Page 7: ...3 13 RETAINER PLATE 2 AT566A 14 PISTON CUP 2 AT280 15 FAN 1 AP108A 15A FAN LEAD END 1 AP108 16 GRILLE SHROUD 1 AP107 17 O RING 4 AK846 18 TUBE 2 AP125A 19 VALVE PLATE ASSEMBLY 2 AP102A SERVICE KIT 1 K797 EXPLODED PRODUCT VIEW PARTS ORDERING INFORMATION Underside View 75R shown Item not shown Denotes parts included in the Service Kit Parts listed are for stock models For specific OEM models please ...

Page 8: ...ck power source Voltage wrong Check power source Worn cup piston hitting cylinder Replace Cylinder misadjustment Realign Leaky hose or check valve Replace Dirt or liquid on top of piston Inspect and clean Motor not wired correctly Check wiring diagram line voltage Blown head gasket Replace TROUBLESHOOTING CHART www gastmfg com ISO 9001 14001 CERTIFIED PART NO 70 6850 G496PL REV D World Headquarter...

Reviews: