Aircraft Starter Lines » From Hartzell Engine Technologies
For over 20 years Hartzell Engine Tech aircraft starters have been providing the best service to airplane owners, pilots, OEM and flight training schools worldwide. We start up your Lycoming, Continental, & Experimental engines knowing each and every aircraft starter that rolls off the line reveals True Aviation Design & Developement. Ready to Fly!
Select from our Lycoming engine Aircraft Starters or Continental engine Aircraft Starters below:
The E-Drive aircraft starter for Lycoming engines has the toughest duty cycle in the industry, exceeding other starters by 40%. Ready to Fly, for weekend flyers or hard starting flight schools.

The E-Drive is the only aircraft starter that offers Ultimate Kick-back Protection. You can have kick-backs all day and never hurt the E-Drive starter. Because at Hartzell we believe maintenance free for our customers means no kick-backs, no extra replacement costs, and most importantly More Starts!
E-Drive Starter Features:
- Immune to Kick-Back Damage » No Shear Pin costs here!
- Perfect spin » Sweet spot engine starts. Does not drain your power like other starters.
- Lightweight » Only 9.5 lbs.
- No mechanical Bendix
- Electromechanical solid-state solenoid
- Powerful Permanent Magnet » High Torque Performance
- Easy Installation » Lycoming engines
- Tough » Tested under the most extreme environmental conditions
- FAA/PMA approved
- 2 Year Unlimited Hours Warranty
- Aviation Designed & Developed - No Automotive Aftermarket Parts Used!
- Low Current Draw
- 12 volt or 24 volt
- Superior Duty Cycle
- TBO Starter - Capable of providing Maintenance Free service to your engine's TBO... and beyond.
The X-Drive aircraft starter is the Lightest Starter Available for your Lycoming or Experimental Engine.

The X-Drive starter is one of our most popular models because of it's awesome power and compact size. Targeted toward Lycoming users that want one of the industries lightest but most powerful starter on the market, the X-Drive delivers the same High Torque, Low Current Draw, and superior duty cycle that had previously been available only to the E-Drive Starter customers. The introduction of the X-Drive starter allows Hartzell Engine Technologies to service virtually all OEM and aftermarket Lycoming applications.
The X-Drive is Available in Left or Right Mounts and uses the same powerful permanent magnet motor as the E-Drive. Experimental/Homebuilt owners get the best weight savings with the X-Drive and it's small size makes for easy installations.
X-Drive Starter Features:
- Lightest Starter Available » Weight 7.6 lbs.
- Perfect spin » Sweet spot engine starts. Does not drain your power like other starters.
- Start efficiency » Lowest inrush & operating current draw in the industry
- No mechanical Bendix
- Electromechanical solid-state solenoid
- Powerful Permanent Magnet » High Torque Performance
- Easy Installation » Left or Right engine mount
- FAA/PMA Approved
- 2 Year Unlimited Hours Warranty *
- Aviation Designed & Developed - No Automotive Aftermarket Parts Used!
- Environmentally Tested - Under the most extreme conditions
- 12 volt or 24 volt
- Superior Duty Cycle
- TBO Starter - Capable of providing Maintenance Free service to your engine's TBO... and beyond.
Upgrade your Continental Engine with a M-Drive Starter. Recommended protection for ALL starter adapters (classic, Permold, Sand cast etc.)

Introducing the newest starter offered by Hartzell Engine Technologies, the M-Drive aircraft starter. The M-Drive is the lightest starter, designed specifically for starting Large-bore Continental engines, that truly protects your Continental (formerly TCM) starter adapter with a unique internal solenoid.
The M-Drive Starter's electromechanical solenoid completely disengages, immediately releasing the wrap spring, safely protecting your TCM starter adapter - Read more about M-Drive Starter adapter disengagement
With a proven 2.8kw high torque motor, the new M-Drive can start even the hardest cranking large bore Continental engines while safely disengaging from the starter adapter. A perfect replacement for the old heavyweights or Iskra starters.
M-Drive Features:
- Safely Disengages from the starter adapter
- Protects All Continental adapters
- No Back-Torque » Drive Shaft spins free
- Lightweight » Only 7.5 lbs.
- Internal Solenoid » No Bendix
- Performance » Powerful permanent magnet - High Torque
- Easy Installation » Direct Continental Motors factory starter mount (No Clearance Issues!)
- Tough » Tested under the most extreme environmental conditions
- FAA/PMA approved
- Aviation Designed & Developed - No Automotive Aftermarket Parts Used!
- 2 Year Unlimited Hours Warranty
- Low Current Draw
- 12 volt or 24 volt
- Superior Duty Cycle
- TBO Starter - Capable of providing Maintenance Free service to your engine's TBO... and beyond.
Performance:
We know Performance is the most important aspect and what you want in a new aircraft starter! The important key measurements in assessing a starter's performance are engine Cranking Speed (rpm), electric Current Draw (amps), and Duty Cycle.
Toughest Duty Cycle in the Industry =
More Starts:
Our duty cycle limitation exceeds other starter designs by over 40%. Hartzell Engine Technologies aircraft starters achieve improved duty cycle results in lower operational temperatures, thus a longer starter life.
Bottom line this means more starts, lower maintenance, and less cost to you!
Engineering Excellence:
Each of our aircraft starters provide High Torque, Low Inrush & Operating
Current Draw, and a Superior Duty Cycle. Along with major weight savings from
the old Prestolite heavyweights, the new Hartzell starters are suitable for installation
on All Lycoming Engines without modification.
Design & Source Control:
It is vital to understand the importance of a part being
Aviation Designed & Developed. Hartzell believes in engineering products
specifically for the aviation industry and has design and source control
over all components. Absolutely no automotive aftermarket parts are
used, unlike our compeditors.
Each aircraft starter from Hartzell Engine Technologies uses a High Torque - Permanent Magnet Motor = More Power
- High Performance Armature
- Increased commutator bar length
- Thin laminations
- High quality magnetic alloy - 12 & 24 volt winding configuration
- Redesigned Brush Holder
- Metal construction for heat sinking
- Offset brush position for increased brush contact area - Robust spring design
- High performance field housing
- Rare earth neodymium magnets
- Small package
- Stronger flux field - Improved temperature stability
X-Drive
Starter - Available in Left or Right Mount:
(12/14 pitch works on a 149 tooth
ring gear & 10/12 pitch works on
a 122 tooth ring gear)
Solenoid
to the Left:
X-Drive starter series - Figure 1
| Part Number: |
Volts: |
Pitch Gear: |
| SRB-9021 |
24 v | 12/14 |
| SRB-9022 | 24 v | 10/12 |
| SRZ-9021 | 12 v | 12/14 |
| SRZ-9022 | 12 v | 10/12 |
Solenoid to the Right:
X-Drive starter series - Figure 2
| Part Number: |
Volts: |
Pitch Gear: |
| SRB-9031 |
24 v | 12/14 |
| SRB-9032 | 24 v | 10/12 |
| SRZ-9031 | 12 v | 12/14 |
| SRZ-9032 | 12 v | 10/12 |
M-Drive Aircraft Starter from Hartzell Engine Technologies - Safely Protects Your TCM Starter Adapter.
The "TCM Starting System" consisting of both a starter motor and a TCM Starter Adapter (classic Permold or Sand Cast) has been a very successful design for many years. Legacy (heavyweight, direct drive) starter motors from Delco, Prestolite, & Energizer have provided trouble-free service oftentimes through engine TBO. Recent market demands have stressed higher performance, lighter weight, longer design life, and lower current draw. Twenty-first century technology allows these improvements in the starter motor... but, that is just one-half of the TCM starting system. Powerful high strength permanent magnet, gear reduction motors have been designed to satisfy these market demands, but one inherent characteristic of all gear reduction motors is that they DO NOT 'turn backward'.
With the TCM starter system a key operating characteristic is that once the engine starts, it is necessary for the starter motor shaft to 'turn backward' only slightly to release the wrap spring tension and disengage the starter motor from the TCM starter adapter. If the motor resists reverse movement, the wrap spring tension is maintained on the starter adapter drive shaft after the engine starts causing excessive wear of the spring & shaft, eventually resulting in slippage or catastrophic damage requiring removal and overhaul of the TCM starter adapter. Repair or replacement may cost several thousand dollars.
Having been the OE starter motor supplier for 25 years, HET was aware of these requirements and designed the M-Drive lightweight aircraft starter to perform as successfully as its larger predecessors. Reducing the reverse torque to near zero was accomplished by designing an in-line solenoid that electrically connects the starter motor to the starter adapter drive shaft.
When the ignition key is released at engine start the solenoid completely disengages, immediately releasing the wrap spring drive tension, thus allowing the starter adapter drive shaft to rotate freely without damage.
No other lightweight gear-reduction starter has this low back-torque feature which precludes damage to your TCM starter adapter by the starter motor. When you are looking for a new starter for your TCM engine, ask for the M-Drive from Hartzell Engine Technologies. It is available in 12 volt (MRZ-7000) and 24 volt (MRB-7000) models and is FAA certified and PMA approved.
E-Drive Starter vs. Sky-tec 149-NL
Cranking Speed (rpm)
is the speed at which your starter rotates the engine's crankshaft during a start. You may think that a higher cranking speed would be better but this is not always the case. Your starter is part of the engine's starting system which also includes the fuel and ignition systems. These systems have been designed to provide good starting characteristics for a particular starting speed range. For most engines this speed is between 120 and 180 rpm. Cranking your engine faster than 200 rpm may disengage the magneto impulse couplings thereby advancing the ignition timing which will result in poor engine starting and can even induce kickbacks! A typical 6 cylinder Lycoming engine requires 50-60 ft*lbs of torque to start. For this load condition, consider the following comparison (see chart, point B for Edrive and point D for Sky-Tec).
- Sky-Tec - Spins the engine too fast
295/305 rpm at 50 ft*lbs of torque.
- E-Drive - Ideal cranking, well below limit
145/155 rpm at 50 ft*lbs of torque.
Current Draw
directly affects the amount of heat that builds up in your starter when cranking your engine. The more current your starter pulls, the more heat that is generated in the starter. Increased heat reduces cranking performance, shortens the overall life of your starter and drains your battery. The rate of temperature increase also decreases the duty cycle of the starter which means fewer starts before the starter reaches its temperature limit. Current draw also affects other components in the aircraft starter electrical system. Contactors, terminals, and cables are all adversely affected by high current draw. Current draw is particularly important to pilots who have the battery located in the rear of the aircraft. The cable between the battery and the starter acts as a resistor which causes a voltage drop over its length. As current increases so does this voltage drop. The resulting electrical power lost to heat over the length of the cable is not available for use by the starter. Higher current draw results in greater voltage drop and less power to the starter. For cranking a typical Lycoming 6-cylinder engine with a 24-volt system and assuming a 50 ft*lb torque load the following comparison should be considered (see chart).
- Sky-Tec - Pulls about 2-1/2 times as much current, shortening starter life
165/175 amps
- E-Drive - More than Double the number of starts and duty cycle of Sky-Tec!
60/70 amps
Current Draw also determines the number of starts you can get from your battery. For a given charge condition, your battery is capable of delivering a given number of starts and that number is directly related to the amount of current your starter draws while cranking. A starter drawing twice the current will only give you half the number of starts before battery depletion.
Duty Cycle
is important as it reflects how well the starter can tolerate repeated starting attempts and over-cranking abuse. Warranty data from starter manufacturers indicates that the principle cause of in-service starter motor failures is over-cranking abuse. A starter with a duty cycle twice that of another will be able to deliver twice the number of starts within a given window of time without overheating. This is an important performance indicator when considering a starter as it will have a direct impact on starter longevity.
The operational limitations for the E-Drive are 10-seconds of engagement time followed by 20-seconds of rest for 20 consecutive starts! No other starter can match that kind of performance!
The Hartzell starters have undergone rigorous durability & laboratory tests including operating at temperatures ranging from -45 to 180°F shock tests, sinusoidal vibration sweeps, load cycling, normal starting, abusive starting, starting with induced kick-backs, and other environmental/operational extremes. The new starter lines from Hartzell Engine Technologies are capable of providing maintenance free service to your engine's TBO... and beyond.
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