Cat ®

304
Mini Excavator

Features:
The Cat® 304 Mini Excavator delivers power and performance SAFETY ON THE JOB SITE
in a compact size to help you work in a wide range of applications. „ Your safety is our top priority. The Cat mini excavator is designed to
help keep you safe on the job. Courtesy work lights and a fluorescent
ALL DAY COMFORT retractable seat belt are just a couple of the safety features we’ve built
„ Choose either a canopy (not available in some regions) or a sealed into the machine.
and pressurized cab which can be equipped with air conditioning,
adjustable wrist rests, and a suspension seat to help keep you working SIMPLE SERVICE FOR LESS DOWNTIME
comfortably all day long. „ Maintenance is quick and easy on the Cat mini excavator. Routine
check points are easy to access at ground level through the side doors.
EASY TO OPERATE
„ Controls are easy to use and the intuitive Next Generation LCD monitor LOWER OPERATING COSTS
provides easy to read machine information. An advanced touchscreen „ Equipped with features such as auto idle, auto engine shutdown,
monitor can also be equipped as an upgrade option. and efficient hydraulics with a variable displacement pump, the
Cat mini excavator was designed with reducing your operating
STICK STEER TRAVEL MODE costs in mind.
„ Moving around the job site is even easier with the Cat Stick Steer
option. Easily switch from traditional travel controls with levers and UNMATCHED DEALER SUPPORT
pedals to joystick controls to move the machine and to operate the „ YourCat dealer is here to help you reach your business goals.
blade. The benefit of less effort and improved control is in your hands! From providing equipment solutions to operator training to service
needs and beyond, your Cat dealer is ready to help.
BIG PERFORMANCE IN A SMALL MACHINE
„ Strong lift and dig performance helps you get the job done faster.
The reduced radius tail swing design provides exceptional stability
and performance. With a maximum width of 1700 mm (67 in), the
304 can access those hard to get into areas. Dozer float allows for
easy clean up. An angle blade is also an option for finished grading
and easier backfilling applications.

Specifications
Engine Weights
Engine Model C1.7 Turbo Minimum Operating Weight with Canopy* 3925 kg 8,655 lb
Net Power @ 2,400 rpm Maximum Operating Weight with Canopy** 4375 kg 9,647 lb
ISO 9249, 80/1269/EEC 33.6 kW 45.0 hp Minimum Operating Weight with Cab* 4025 kg 8,875 lb
Gross Power @ 2,400 rpm Maximum Operating Weight with Cab** 4475 kg 9,867 lb
SAE J1995:2014 36.1 kW 48.4 hp
**Minimum Weight is based on rubber tracks, operator, full fuel tank,
Bore 84.0 mm 3.3 in
standard stick, straight blade, no bucket and no extra counterweight.
Stroke 100.0 mm 3.9 in
**Maximum Weight is based on steel tracks, operator, full fuel tank,
Displacement 1.662 L 101 in3 long stick, straight blade, extra counterweight and no bucket.
• Meets U.S. EPA Tier 4 Final and EU Stage V emission standards.
• Net power advertised is the power available at the flywheel when
the engine is at rated speed and rated power when the engine
is installed with the factory configured fan, air intake system,
exhaust system, and alternator with a minimum alternator load.
304 Mini Excavator

Weight Increase from Minimum Configuration Sound

Counterweight 225 kg 496 lb Operator Sound Pressure Level 76 dB(A)
Long Stick 30 kg 66 lb (ISO 6396:2008)
Steel Tracks 195 kg 430 lb Exterior Sound Power Level 97 dB(A)
Angle Blade 110 kg 243 lb (ISO 6395:2008)
• European Union Directive “2000/14/EC”
Travel System
Travel Speed – High 5.2 km/h 3.2 mph 7 8
Travel Speed – Low 3.5 km/h 2.2 mph
Maximum Traction Force – High Speed 19 kN 4,271 lbf
Maximum Traction Force – Low Speed 32.6 kN 7,329 lbf 5 20
Ground Pressure – Minimum Weight 28.7 kPa 4.2 psi 6
Ground Pressure – Maximum Weight 33.8 kPa 4.9 psi 12
11
Gradeability (maximum) 30 degrees 9 13
10 21 14
15
Service Refill Capacities 2
1
Cooling System 11.0 L 2.9 gal 16
Engine Oil 6.0 L 1.6 gal 19
17
Fuel Tank 63.0 L 17.0 gal 18
3
Hydraulic Tank 52.0 L 14.0 gal 4
Hydraulic System 65.0 L 17.0 gal Dimensions
Hydraulic System Standard Stick Long Stick
Load Sensing Hydraulics with Variable Displacement Piston Pump 1 Dig Depth 3210 mm (126.4 in) 3510 mm (138.2 in)
Pump Flow @ 2,400 rpm 96 L/min 25 gal/min 2 Vertical Wall 2395 mm (94.3 in) 2535 mm (99.8 in)
Operating Pressure – Equipment 245 bar 3,553 psi 3 Maximum Reach 5200 mm (204.7 in) 5445 mm (214.4 in)
Operating Pressure – Travel 245 bar 3,553 psi at Ground Level
Operating Pressure – Swing 180 bar 2,611 psi 4 Maximum Reach 5330 mm (209.8 in) 5570 mm (219.3 in)
Auxiliary Circuit – Primary
5 Maximum Dig Height 5040 mm (198.4 in) 5125 mm (201.8 in)
Flow* 65 L/min 21 gal/min
Pressure* 245 bar 3,553 psi 6 Maximum Dump Clearance 3645 mm (143.5 in) 3740 mm (147.2 in)
Auxiliary Circuit – Secondary 7 Boom in Reach 2255 mm (88.8 in) 2340 mm (92.1 in)
Flow* 28 L/min 7.0 gal/min 8 Tail Swing
Pressure* 245 bar 3,553 psi without Counterweight 1205 mm (47.4 in) 1205 mm (47.4 in)
Digging Force – Stick (standard) 21.0 kN 4,721 lbf
Digging Force – Stick (long) 19.2 kN 4,316 lbf with Counterweight 1300 mm (51.2 in) 1300 mm (51.2 in)
Digging Force – Bucket 38.2 kN 8,588 lbf 9 Maximum Blade Height 420 mm (16.5 in) 420 mm (16.5 in)
10 Maximum Blade Depth 475 mm (18.7 in) 475 mm (18.7 in)
*Flow and pressure are not combinable. Under load, as flow rises
pressure goes down. 11 Boom Height in 1620 mm (63.8 in) 1910 mm (75.2 in)
Shipping Position
Swing System 12 Overall Shipping Height 2540 mm (100.0 in) 2540 mm (100.0 in)
Machine Swing Speed 9.0 rpm 13 Swing Bearing Height 557 mm (21.9 in) 557 mm (21.9 in)
Boom Swing – Left 78 Degrees 14 Overall Undercarriage Length 2210 mm (87.0 in) 2210 mm (87.0 in)
Boom Swing – Right 50 Degrees 15 Overall Shipping Length† 4950 mm (194.9 in) 4950 mm (194.9 in)
16 Boom Swing Right 730 mm (28.7 in) 730 mm (28.7 in)
Blade
17 Boom Swing Left 530 mm (20.9 in) 530 mm (20.9 in)
Width (Straight) 1700 mm 66.9 in
Height (Straight) 360 mm 14.2 in 18 Track Belt/Shoe Width 350 mm (13.8 in) 350 mm (13.8 in)
Width (Angle) 1700 mm 66.9 in 19 Track Width 1700 mm (66.9 in) 1700 mm (66.9 in)
Height (Angle) 360 mm 14.2 in 20 Ground Clearance 305 mm (12.0 in) 305 mm (12.0 in)
Angle Blade – Left 25 Degrees 21 Stick Length 1395 mm (54.9 in) 1695 mm (66.7 in)
Angle Blade – Right 25 Degrees
†Overall Shipping Length depends on blade position during shipment.
Certification – Cab and Canopy
Roll Over Protective Structure (ROPS) ISO 12117-2:2008
Tip Over Protective Structure (TOPS) ISO 12117:1997
Top Guard ISO 10262:1998 Level I

2
 304 Mini Excavator

Cab
Lift Capacities – Lift Point Radius – 3 m (9.8 ft) Lift Point Radius – 4.5 m (14.8 ft) Lift Point Radius (Maximum)
Minimum Configuration Over Front Over Front Over Front m
Lift Point Height Blade Down Blade Up Over Side Blade Down Blade Up Over Side Blade Down Blade Up Over Side (ft)
kg *941 *941 *941 *698 *698 *698 4.09
Standard Stick
3m (lb) (*2,075) (*2,075) (*2,075) (*1,539) (*1,539) (*1,539) (13.4)
(9.8 ft) kg *699 *699 *699 4.37
Long Stick
(lb) (*1,541) (*1,541) (*1,541) (14.3)
kg *1522 1213 1031 *1040 662 573 *698 *698 555 4.59
Standard Stick
1.5 m (lb) (*3,356) (2,675) (2,273) (*2,293) (1,460) (1,263) (*1,539) (*1,539) (1,224) (15.1)
(4.9 ft) kg *1333 *1333 1029 *1008 652 562 *711 582 502 4.84
Long Stick
(lb) (*2,939) (*2,939) (2,269) (*2,223) (1,438) (1,239) (*1,568) (1,283) (1,107) (15.9)
kg *2006 1148 969 *846 656 566 4.46
Standard Stick
0m (lb) (*4,423) (2,531) (2,137) (*1,865) (1,446) (1,248) (14.6)
(0 ft) kg *1933 1128 950 *1142 630 541 *861 591 508 4.71
Long Stick
(lb) (*4,262) (2,487) (2,095) (*2,518) (1,389) (1,193) (*1,899) (1,303) (1,120) (15.5)
Minimum Weight includes cab, rubber tracks, no counterweight, operator, full fuel tank and straight blade.

Lift Capacities – Lift Point Radius – 3 m (9.8 ft) Lift Point Radius – 4.5 m (14.8 ft) Lift Point Radius (Maximum)
Maximum Configuration Over Front Over Front Over Front m
Lift Point Height Blade Down Blade Up Over Side Blade Down Blade Up Over Side Blade Down Blade Up Over Side (ft)
kg *941 *941 *941 *698 *698 *698 4.09
Standard Stick
3m (lb) (*2,075) (*2,075) (*2,075) (*1,539) (*1,539) (*1,539) (13.4)
(9.8 ft) kg *699 *699 *699 4.37
Long Stick
(lb) (*1,541) (*1,541) (*1,541) (14.3)
kg *1522 *1522 1266 *1040 780 714 *698 *698 *698 4.59
Standard Stick
1.5 m (lb) (*3,356) (*3,356) (2,792) (*2,293) (1,720) (1,574) (*1,539) (*1,539) (*1,539) (15.1)
(4.9 ft) kg *1333 *1333 *1333 *1008 769 703 *711 *711 *711 4.84
Long Stick
(lb) (*2,939) (*2,939) (*2,939) (*2,223) (1,696) (1,550) (*1,568) (*1,568) (*1,568) (15.9)
kg *2006 1349 1204 *846 *846 709 4.46
Standard Stick
0m (lb) (*4,423) (2,975) (2,655) (*1,865) (*1,865) (1,563) (14.6)
(0 ft) kg *1933 1329 1185 *1142 748 682 *861 702 641 4.71
Long Stick
(lb) (*4,262) (2,930) (2,613) (*2,518) (1,649) (1,504) (*1,899) (1,548) (1,413) (15.5)
Maximum Weight includes cab, steel tracks, counterweight, operator, full fuel tank and angle blade.

Canopy
Lift Capacities – Lift Point Radius – 3 m (9.8 ft) Lift Point Radius – 4.5 m (14.8 ft) Lift Point Radius (Maximum)
Minimum Configuration Over Front Over Front Over Front m
Lift Point Height Blade Down Blade Up Over Side Blade Down Blade Up Over Side Blade Down Blade Up Over Side (ft)
kg *941 *941 *941 *698 *698 *698 4.09
Standard Stick
3m (lb) (*2,075) (*2,075) (*2,075) (*1,539) (*1,539) (*1,539) (13.4)
(9.8 ft) kg *699 *699 585 4.37
Long Stick
(lb) (*1,541) (*1,541) (1,290) (14.3)
kg *1522 1176 1000 *1040 640 555 *698 *698 537 4.59
Standard Stick
1.5 m (lb) (*3,356) (2,593) (2,205) (*2,293) (1,411) (1,224) (*1,539) (*1,539) (1,184) (15.1)
(4.9 ft) kg *1333 *1333 999 *1008 630 544 *711 562 485 4.84
Long Stick
(lb) (*2,939) (*2,939) (2,203) (*2,223) (1,389) (1,200) (*1,568) (1,239) (1,069) (15.9)
kg *2006 1111 939 *846 634 548 4.46
Standard Stick
0m (lb) (*4,423) (2,450) (2,070) (*1,865) (1,398) (1,208) (14.6)
(0 ft) kg *1933 1091 919 *1142 608 523 *861 570 490 4.71
Long Stick
(lb) (*4,262) (2,406) (2,026) (*2,518) (1,341) (1,153) (*1,899) (1,257) (1,080) (15.5)
Minimum Weight includes canopy, rubber tracks, no counterweight, operator, full fuel tank and straight blade.

Lift Capacities – Lift Point Radius – 3 m (9.8 ft) Lift Point Radius – 4.5 m (14.8 ft) Lift Point Radius (Maximum)
Maximum Configuration Over Front Over Front Over Front m
Lift Point Height Blade Down Blade Up Over Side Blade Down Blade Up Over Side Blade Down Blade Up Over Side (ft)
kg *941 *941 *941 *698 *698 *698 4.09
Standard Stick
3m (lb) (*2,075) (*2,075) (*2,075) (*1,539) (*1,539) (*1,539) (13.4)
(9.8 ft) kg *699 *699 *699 4.37
Long Stick
(lb) (*1,541) (*1,541) (*1,541) (14.3)
kg *1522 *1522 1235 *1040 758 696 *698 *698 *698 4.59
Standard Stick
1.5 m (lb) (*3,356) (*3,356) (2,723) (*2,293) (1,671) (1,535) (*1,539) (*1,539) (*1,539) (15.1)
(4.9 ft) kg *1333 *1333 *1333 *1008 748 685 *711 *711 *711 4.84
Long Stick
(lb) (*2,939) (*2,939) (*2,939) (*2,223) (1,649) (1,510) (*1,568) (*1,568) (*1,568) (15.9)
kg *2006 1312 1174 *846 *846 691 4.46
Standard Stick
0m (lb) (*4,423) (2,893) (2,589) (*1,865) (*1,865) (1,524) (14.6)
(0 ft) kg *1933 1292 1154 *1142 726 664 *861 681 624 4.71
Long Stick
(lb) (*4,262) (2,849) (2,545) (*2,518) (1,601) (1,464) (*1,899) (1,502) (1,376) (15.5)
Maximum Weight includes canopy, steel tracks, counterweight, operator, full fuel tank and angle blade.
*The above loads are in compliance with hydraulic excavator lift capacity rating standard ISO 10567:2007 and they do not exceed 87% of hydraulic lifting capacity or 75% of tipping capacity.
The excavator bucket weight is not included on this chart.

3
304 Mini Excavator
Standard and Optional Equipment
Standard and optional equipment may vary. Consult your Cat dealer for details.

Standard Optional Standard Optional

ENGINE OPERATOR ENVIRONMENT (continued)
Cat® C1.7 Turbo Engine (U.S. EPA Tier 4 Final/EU Stage V)  Next Generation Color LCD Monitor (IP66) 
Automatic Engine Idle  – Fuel Level and Coolant Temperature Gauges 
Automatic Engine Shutdown  – Maintenance and Machine Monitoring 
Automatic Two Speed Travel  – Performance and Machine Adjustments 
Fuel Water Separator  – Numeric Security Code 
Power on Demand (not available in all regions)  – Multiple Languages 
Variable Displacement Piston Pump  – Hour Meter with Wake Up Switch 
Load Sensing/Flow Sharing Hydraulics  – Jog Dial (cab only) 
HYDRAULICS Next Generation Advanced Monitor 
Smart Tech Electronic Pump  – Touch Screen 
Accumulator  – Site Reference System 
Automatic Swing Brake  – High Definition Camera Capable (IP68 and IP69K) 
Auxiliary Hydraulic Lines  – Numeric Security Code 
One and Two Way Auxiliary Flow  UNDERCARRIAGE
Continuous Auxiliary Flow  Rubber Belt (350 mm/13.8 in) 
Auxiliary Line Quick Disconnects  Steel Track (350 mm/13.8 in) 
OPERATOR ENVIRONMENT Steel Track with Rubber Pads 
Canopy or Cab (Canopy not available in some regions)  Dozer Straight Blade 
Cab with Air Conditioning  Dozer Blade Float 
Cab with Heater  Angle Blade 
Top Guard ISO 10262:1998 Level I  Tie Downs on Track Frame 
ROPS – ISO 12117-2:2008  BOOM, STICK AND LINKAGES
TOPS – ISO 12117:1997  One Piece Boom (2500 mm/98.4 in) 
Stick Steer Mode  Standard Stick (1395 mm/54.9 in) 
Travel Cruise Control  Long Stick (1695 mm/66.7 in) 
Control Pattern Changer (optional in some regions)  Front Shovel Capable 
Adjustable Wrist Rests  Pin-On 
Washable Floor Mat  Dual Lock Manual Coupler 
Travel Pedals and Hand Levers  Hydraulic Coupler 
No Travel Pedals and Hand Levers  Thumb Ready 
(optional in some regions) Certified Lifting Eye 
Machine Security  Attachments including Couplers, Thumbs, Buckets, 
Standard Key with Pass Code  Augers and Hammers
Push to Start with Key Fob/Pass Code  2nd Auxiliary Hydraulic Lines 
Fabric Suspension Seat (Cab only)  Bucket Divert Lines 
Vinyl Suspension Seat (Canopy only)  Boom Lowering Check Valve 
Hydraulic Lockout – All Controls  Stick Lowering Check Valve 
Retractable High Visibility Seat Belt (75 mm/3 in)  Hydraulic Quick Coupler Lines 
Coat Hook  ELECTRICAL
Cup Holder  12 Volt Battery 
Storage Pocket  Software (machine and monitor) 
Skylight  Maintenance Free Battery 
Mounting Bosses for Front  Battery Disconnect 
Signaling/Warning Horn  12 Volt Power Socket 
Interior Light (Cab only)  Product Link™ PL243 (regulations apply) 
Boom Light, Halogen (not available in all regions)  Product Link PLE643 (regulations apply) 
LED Front Lights  Travel Alarm (optional in some regions) 
LED Front and Rear Lights  GUARDING
LED Boom Light  Polycarbonate Half Height Front Guard (Canopy only) 
Utility Space for Mobile Phone  Polycarbonate Front Guard (ISO 10262:1998 Level I and 
Mirrors, Left, Right and Rear  EN356 P5A)
Camera  Heavy Duty Front Guard ISO 10262:1998 Level II 
Radio – Bluetooth®, Auxiliary, Microphone,  Heavy Duty Top Guard 10262:1998 Level II (Cab only) 
USB (charging only) (Cab only) OTHER
Bio Oil Capable 
Eco Drain 
Water Jacket Heater 
Counterweight (225 kg/496 lb) 

For more complete information on Cat products, dealer services, and industry solutions, visit us on the web at www.cat.com AEHQ8377-01 (09-2021)
© 2021 Caterpillar Replaces AEHQ8377
All rights reserved Build Number: 07A
(North America, Europe,
Materials and specifications are subject to change without notice. Featured machines in photos may include additional
equipment. See your Cat dealer for available options.
Australia/New Zealand)

CAT, CATERPILLAR, LET’S DO THE WORK, their respective logos, “Caterpillar Corporate Yellow,” the “Power Edge”
and Cat “Modern Hex” trade dress as well as corporate and product identity used herein, are trademarks of Caterpillar
and may not be used without permission.