The M300 Excavators are the replacement for the 206B Excavator, 212B Excavator, 214B Excavator, 214B FT Excavator and 224B Excavator. These models are designed in order to reflect the latest technology and features. The machines have a broad range of boom-stick-bucket combinations which provide maximum versatility.
These new excavators can be driven on the highways at speeds of 32 km/h (20 mph). Some machines are limited in travel speed to 20 km/h (12 mph). All machines are equipped with two-speed transmissions. This provides speeds for highway use, movement over rough terrain or soft terrain. A creeper speed in the transmission is standard equipment. This ensures that the travel motor is at the maximum angle for maximum torque and low speed operation.
The machines can be equipped with various attachments and stabilizer and blade combinations. The machines can be set up with the following configurations:
- Two point stabilizers
- Four point stabilizers
- Two point stabilizers with blade
Comparisons With Former Machines
The M312 Excavator and M315 Excavator are equipped with 3054 DIT Caterpillar engines. The M318 Excavators and M320 Excavators are equipped with 3116 DIT Caterpillar engines.
The undercarriage that is below the swing bearing is similar to the former machines.
The transmission is very similar to the transmissions on the 206B Excavator and 212B Excavator.
The steering system has the same type of gear pump as the former machines, but the location of the steering pump is different.
The pilot system flow divider valve diverts 15 L/min (4 US gpm) from the brake pump flow for the pilot control system.
Differences From Former Machines
The main pump is a variable displacement piston pump with a swashplate that is a load sensing and pressure compensated pump. Flow rates from the pumps are very similar to the pumps on the former machines.
The swing pump is a closed loop variable displacement piston pump with a swashplate that operates independently from the main hydraulic pump. When the pump is in hold, the swing pump swashplate is at a zero degree angle and the oil flow is not available. The pump will upstroke in either direction in order to cause the machine to swing to the right or to the left. The swing pump has an independent positive displacement internal gear type charge pump which maintains the charge system pressure in the swing circuit. Pilot pressure is used to upstroke the swing pump.
The main hydraulic control valve is changed. The flow compensator valves are separate from the control valves. The flow compensator valves are not located inside the spools.
The Electronic Control Unit (ECU) is similar to the ECU in the 300B Excavators. The ECU helps regulate the flow from the main hydraulic pump and the swing pump.
The pilot manifold now has one valve housing and the pilot filter is external instead of being internal. The filter is located under the cab on all machines.
An attachment of a hydraulic cab riser has been added to the M318 Excavator and to the M320 Excavator.