What is the maximum operating pressure for the ATS83 and ATS84 turbine air starters?

Both the ATS83 and ATS84 turbine air starters are rated to a maximum supply pressure of 150 psi. The recommended standard operating pressure is 100 psi, which delivers optimal cranking torque and starting performance while keeping all mechanical components within their design limits. Operating above 100 psi toward the 150 psi ceiling should be reserved for applications requiring additional cranking torque and should not be the routine condition. The air receiver must comply with an applicable pressure vessel code such as AS1210 or equivalent standard.

What is the difference between the ATS83 and ATS84 turbine air starters?

The ATS83 Series 2 and ATS84 share the same turbine motor and silencer assemblies but differ in their pinion drive mechanism and overall length. The ATS83 uses an inertia drive: as the turbine rotor accelerates, centrifugal force drives the pinion outward along a helical spline to engage with the engine ring gear, then retracts automatically once the engine fires. The ATS84 uses a pre-engaged pneumatic piston drive, where compressed air pressure pushes the pinion positively into mesh with the ring gear before the turbine begins spinning. The ATS84 is also longer overall at 17.063 inches (433.4 mm) versus 12.045 inches (305.9 mm) for the ATS83-2, reflecting its more substantial pre-engaged nose assembly.

What flange standard do the ATS83 and ATS84 use?

Both models use an SAE 3 flange with a 3-hole bolt pattern on a 5.750-inch pitch circle diameter, using 21/32-inch holes equally spaced. This positions them for use on large-bore diesel and gas engines such as Caterpillar 3408 and Waukesha 7072, and similarly sized industrial and power generation engines where the SAE 3 flywheel housing is standard. Unlike the smaller ATS63/64 series which spans SAE 1 through 4, the ATS83/84 is purpose-built for the SAE 3 application.

Can the housing orientation be adjusted without full disassembly?

Yes. Both the ATS83 and ATS84 use a band clamp connection between the motor housing and nose assembly that allows continuous 360-degree rotation of the two sections relative to each other without separating the sub-assemblies. Simply loosen the band clamp without removing it, rotate the housing to the desired port orientation, and re-torque to 4 ft lb (6 Nm). This makes it straightforward to redirect the air inlet and control ports to the most convenient angle for hose routing in space-constrained engine compartments.

Turbine Air Starters

Turbine Driven | 150 psi Rated | SAE 3 Flange

Engine Starting Systems · Turbine Air Starters · Pneumatic Starters

Austart ATS83 & ATS84 Turbine Air Starters – High-Capacity Pneumatic Engine Starting for Large-Bore Diesel and Gas Engines

The Austart ATS83 and ATS84 turbine air starters are heavy-duty compressed air-driven cranking systems purpose-built for demanding large-bore engine starting across mining, oil and gas, marine, and stationary power generation environments. Spark-free by design and rated to a maximum of 150 psi, both models convert compressed air into high cranking torque through a precision turbine rotor and three-planet epicyclic gear reduction, delivering that torque to the engine flywheel via an SAE 3 flanged pinion assembly. The ATS83 Series 2 uses an inertia drive mechanism for automatic pinion engagement, while the ATS84 uses a pre-engaged pneumatic piston drive for positive pinion mesh before cranking begins — making this series the go-to choice wherever electrical starting is impractical or presents an ignition risk.

Turbine Air Driven

150 psi Max Pressure

360° Indexable Housing

SAE 3 Flange Standard

Key Features

The Austart ATS83 and ATS84 turbine air starters are pneumatically driven cranking systems that harness compressed air to spin a high-speed turbine rotor, then step that rotational energy down through a three-planet epicyclic gear reduction to deliver the torque needed to crank large diesel and gas engines reliably. The ATS83 Series 2 employs an inertia drive for self-actuating pinion engagement, while the ATS84 uses a pneumatic piston pre-engaged drive that positively meshes the pinion with the engine ring gear before the turbine begins spinning. Both models are assembled across three independently serviceable sub-assemblies — nose, motor, and silencer — and are engineered for continuous duty in the most demanding industrial applications, covering large-bore platforms such as the Caterpillar 3408, Waukesha 7072, and comparable high-compression engines.

Turbine-Driven Compressed Air Operation — Fully Spark-Free: The ATS83 and ATS84 operate exclusively on compressed air, with no battery, alternator, or electrical wiring required in the starting circuit. This eliminates ignition risk in classified hazardous areas such as oil and gas wellheads, gas compression stations, and underground mining environments, where electrical spark-generating equipment demands costly explosion-proof certification. The turbine rotor delivers consistent cranking torque across the full operating pressure range from the standard 100 psi up to the 150 psi maximum, maintaining reliable starting capability even when air receiver pressure is not at its peak level.
Dual Drive Architecture: Inertia (ATS83) and Pre-Engaged Piston (ATS84): The ATS83 Series 2 inertia drive uses the centrifugal force produced by the accelerating output shaft to extend the pinion along a helical spline into engagement with the engine ring gear, then automatically withdraws the pinion once the engine fires and its rotational speed overtakes the starter. The ATS84 pre-engaged drive uses a pneumatically actuated internal piston to push the pinion positively into mesh with the ring gear before the turbine rotor begins spinning, guaranteeing full tooth engagement at the moment of maximum cranking torque demand. This choice of drive type allows engineers and procurement teams to specify the architecture best suited to each engine's ring gear geometry and the application's starting duty requirements.
SAE 3 Flange for Large-Bore Engine Compatibility: Both the ATS83 and ATS84 are built to SAE 3 flywheel housing standard, with a 3-hole bolt pattern on a 5.750-inch pitch circle diameter. This positions them squarely in the large industrial engine starting bracket, covering platforms such as Caterpillar 3408, Waukesha 7072, and other large-bore diesel and gas engines where the SAE 3 housing is standard. The flange mounts directly and squarely to the engine flywheel housing without adaptors, ensuring proper pinion-to-ring-gear alignment from the first installation and throughout the service life of the starter.
360° Indexable Housing for Installation Flexibility: The connection between the motor housing and nose assembly is secured by a band clamp that allows the two sections to be rotated relative to each other through a continuous 360 degrees without separating the sub-assemblies. Loosening the band clamp, rotating to the required port orientation, and re-torquing to 4 ft lb (6 Nm) is all that is required to redirect the air inlet and control ports to the most convenient angle for hose routing. This adjustability significantly simplifies installation on engines where access to the flywheel housing is restricted from certain directions, and allows the starter to be re-configured in the field as installation requirements change.
Three-Planet Epicyclic Gear Reduction for High Cranking Torque: Inside the nose assembly, a three-planet epicyclic (planetary) gear set reduces the high rotational speed delivered by the turbine rotor to the lower cranking speed required at the engine ring gear, while simultaneously multiplying torque to the level needed to turn over large, high-compression engines. The three planet gears run on precision bearings within the spider hub assembly and are packed with grease during assembly and servicing. This planetary gear reduction is the critical torque-multiplying stage that bridges turbine power and practical engine cranking performance on large-displacement diesel and gas engine platforms.
Integrated Multi-Stage Silencer Assembly: Each ATS83 and ATS84 starter includes a purpose-built muffler assembly that substantially reduces the discharge air noise produced when the starter exhausts at the end of each start cycle. The ATS83-2 uses a compact end cover and outer sleeve muffler arrangement, while the ATS84 features a more elaborate multi-baffle silencer with stacked baffle plates, spacers, and springs that deliver progressive noise attenuation. Optional muffler configurations — including Kelly spinner, short muffler, and threaded exhaust outlets in 1.5-inch, 2-inch, and 3-inch sizes — are available for applications with specific noise management or enclosed-space exhaust routing requirements.
Three-Piece Modular Design for Straightforward Field Servicing: Both starters are built as three distinct, independently serviceable sub-assemblies — the nose assembly (housing the drive mechanism and planetary gear train), the motor assembly (containing the turbine rotor and rotor shaft), and the silencer assembly — held together by two band clamps. A trained technician can disassemble, inspect, and rebuild any sub-assembly independently using standard workshop equipment including a press and circlip pliers, without disturbing the remaining sub-assemblies. A genuine Austart service kit containing all wear-eligible seals, bearings, and O-rings is available to support scheduled maintenance, returning the starter to full factory specification at each service interval.
Mining-Grade Cast Iron Housing Option: For the most demanding mining, quarrying, and heavy extraction applications, both the ATS83 and ATS84 are available in a mining specification variant (suffix M in the part number) with cast iron housing construction. Cast iron provides significantly enhanced resistance to the mechanical impacts, high vibration loads, and contamination characteristic of underground mining, surface mining operations, and drill rig environments, where starter longevity under extreme duty cycles takes priority over minimising unit weight.

Applications

Large Mining Equipment and Haul Trucks: Surface and underground mining operations depend on large-bore diesel engines to power haul trucks, rotary drilling rigs, draglines, excavators, and high-capacity pumping units — often in locations where temperature extremes, vibration, and the absence of reliable electrical infrastructure make battery-based starting impractical or unsafe. The ATS83 and ATS84 turbine air starters operate entirely on compressed air available from the facility's supply network, providing dependable engine starting independent of battery condition and free from the ignition hazards associated with electrical systems in flammable dust or gas environments.
Marine Propulsion and Large Vessel Auxiliary Engines: Commercial vessels, offshore supply boats, platform support vessels, and workboats rely on large diesel engines for propulsion, onboard power generation, fire pumps, and critical auxiliary machinery. The robust construction and spark-free operation of the ATS83 and ATS84 make them well suited to the demanding salt air and high-humidity conditions of the marine environment, where electrical starting systems are prone to corrosion-related failures and where the consequences of a failed engine start can compromise vessel safety and operational continuity.
Oil and Gas Engine-Driven Compression: Gas engine-driven compressors at wellheads, gathering stations, and midstream processing facilities operate in some of the most demanding starting environments — high compression ratios, frequent start cycles, and Zone 1 or Zone 2 classified area electrical requirements. The inherently spark-free operation of the ATS83 and ATS84 turbine starters makes them the standard engineering specification for large gas engine starting in hazardous areas where electrical starting equipment must be certified explosion-proof, while their robust construction supports the high start-duty cycles typical of continuous gas compression service.
Stationary Diesel and Gas Generator Sets: Prime power, standby power, and emergency generation sets using large-bore diesel or gas engines require fast and reliable starting to meet the load pickup times demanded by grid interconnection standards and critical facility backup requirements. The ATS83 and ATS84 deliver the cranking torque needed to turn over high-compression large-displacement engines even at low ambient temperatures, and their independence from the generator's own electrical bus allows the engine to be started during a complete blackout — a capability essential for blackstart and emergency generation applications.
Oil Refineries, Petrochemical Plants, and LNG Facilities: Compressor drivers, pump drivers, and emergency diesel fire pumps in process industries operate in environments where managing ignition risk is a primary engineering requirement and where engine starting system reliability is subject to regulatory scrutiny. The ATS83 and ATS84 series, with optional threaded exhaust outlets and specialist muffler configurations, can be engineered to meet the exhaust management requirements of enclosed machinery rooms and classified area installations, delivering the process reliability and compliance that refinery and gas plant operations require.
Heavy Drilling Rigs and Rotary Drilling Equipment: Large diesel engines driving mud pumps, draw-works, and top-drive systems on onshore and offshore drilling rigs operate in harsh, vibration-intensive environments with high start-frequency requirements. The mechanical durability and modular serviceability of the ATS83 and ATS84 reduce unplanned downtime on drill sites where equipment availability directly affects rig day rates and contractual performance. The mining-grade cast iron housing option provides additional resilience for the most demanding rig applications where conventional aluminium-cased starters experience premature failure.

Technical Specifications

Specifications listed below apply to the Austart ATS83-2 (Series 2) and ATS84 turbine air starters. Model-specific values are indicated where the two variants differ.

Parameter	Specification
Starter Type	Turbine Air Starter (Pneumatic)
ATS83-2 Drive Mechanism	Inertia Drive — Series 2 (centrifugal pinion engagement on acceleration)
ATS84 Drive Mechanism	Pre-Engaged Pneumatic Piston Drive (positive pinion engagement before cranking)
Standard Operating Pressure	100 psi
Maximum Operating Pressure	150 psi
Main Air Inlet	1" NPT (both models)
Control Port Size	1/4" NPT (inlet and outlet)
Minimum Supply Hose I.D. (up to 15 ft / 5 m)	1" (25 mm)
Minimum Supply Hose I.D. (over 15 ft / 5 m)	1-1/2" (40 mm)
Control Line Size	Minimum 1/4" (6 mm) O.D.
ATS83-2 Overall Length	12.045" (305.9 mm)
ATS84 Overall Length	17.063" (433.4 mm)
ATS83-2 Flange to Pinion	1.766" (44.9 mm)
ATS84 Flange to Pinion	1.770" (45.0 mm)
Flange Standard	SAE 3
Flange PCD	5.750" (146.1 mm)
Mounting Hole Pattern	3 holes · Ø 21/32" (16.7 mm) · equally spaced on 5.750" PCD
ATS83-2 Muffler End Diameter	Ø 5.000" (127.0 mm)
Housing Indexing	360° continuous indexing (both models)
Pinion Rest Position	Flange-to-Ring-Gear (FRG) spacing less 1/8" (3 mm)
Pinion Options (Right-Hand)	9TH 3MOD · 10TH 8/10 · 11TH 6/8 · 12TH 8/10
Pinion Options (Left-Hand)	9TH 3MOD · 10TH 8/10 · 11TH 6/8 · 12TH 8/10
ATS83-2 Relay Valve	AR1000 (1" NPT, mounts directly to starter inlet port)
ATS84 Relay Valve	RS1000M (mounts directly to starter inlet port)
Y Strainer	YS1000 · 100 mesh · 1" NPT
Band Clamp Torque	4 ft lb (6 Nm)
Turbine Rotor Special Nut Torque	25–30 ft lb (30–40 Nm)
Re-start Delay	Minimum 15 seconds between start attempts
Mining Specification Option	Cast iron housing (suffix M in part number)
Special Options Available	Inertia drive · Threaded exhaust (1.5", 2", 3") · Kelly spinner muffler · Motor ports 90° · Short/reduced muffler · BCB pinion · U-configuration · ATEX certified
Warranty	12 months from date of purchase (first user)

Technical FAQ

Common Questions Answered

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Both the ATS83 and ATS84 are rated to a maximum supply pressure of 150 psi. The standard recommended operating pressure is 100 psi, which delivers optimal cranking performance while keeping all mechanical loads within design limits. Operating toward the 150 psi ceiling should be reserved for applications that genuinely require additional cranking torque and must not become the routine operating condition. The air receiver must be manufactured to an applicable pressure vessel code such as AS1210 or an equivalent standard.

The ATS83 Series 2 and ATS84 share the same turbine motor and silencer assemblies but differ in their pinion drive mechanism. The ATS83 uses an inertia drive: as the turbine accelerates, centrifugal force drives the pinion into the engine ring gear, and it automatically retracts when the engine fires. The ATS84 uses a pre-engaged pneumatic piston drive that pushes the pinion positively into mesh before the turbine starts spinning, ensuring full engagement at the moment of maximum cranking torque. The ATS84 is also longer overall — 17.063 inches (433.4 mm) versus 12.045 inches (305.9 mm) for the ATS83-2 — reflecting its more substantial pre-engaged nose assembly.

Both models use an SAE 3 flange with a 3-hole bolt pattern on a 5.750-inch pitch circle diameter. This targets large-bore diesel and gas engines — such as the Caterpillar 3408 and Waukesha 7072 — where the SAE 3 flywheel housing is standard. Unlike the smaller ATS63/64 series, which spans SAE 1 through 4, the ATS83/84 is purpose-engineered for SAE 3 applications requiring higher cranking capacity. No adaptor flanges are required; the starter mounts directly to the engine flywheel housing.

The ATS83-2 uses the AR1000 relay valve (1-inch NPT) and the ATS84 uses the RS1000M — both mount directly onto the starter air inlet port using two screws and the sealing O-ring provided. Both models require the YS1000 Y strainer (100 mesh, 1-inch NPT) installed upstream of the relay valve to protect the starter internals from contamination accumulated in the air receiver. A 1/4-inch control line connects the SC25 starter control button to the relay valve and starter motor to complete the pneumatic control circuit. Installing the Y strainer is also a mandatory condition of the product warranty.

A minimum of 15 seconds must elapse between consecutive start attempts. This pause allows all rotating components — including both the starter turbine and the engine — to come to a complete stop before the starter is re-engaged. Attempting to restart while any component is still rotating can cause severe damage to the pinion, ring gear, and internal drive components, and will void the product warranty. Always visually confirm that all components have fully stopped before initiating the next start attempt.

The ATS83 and ATS84 series support 9-tooth 3 MOD, 10-tooth 8/10 pitch, 11-tooth 6/8 pitch, and 12-tooth 8/10 pitch pinions in both right-hand and left-hand configurations. Additional options include mining-grade cast iron housing (suffix M), threaded exhaust outlets in 1.5-inch, 2-inch, and 3-inch sizes, Kelly spinner muffler, motor ports at 90 degrees, Beryllium Copper Bronze pinion (BCB), and U-configuration. ATEX-certified variants are also available for the most demanding classified area applications. Please provide your engine make, model, and ring gear specification so we can confirm the correct full part number for your application.