Hartzell Engine Technology Sites

Service Documents

We need to occasionally inform owners about service information that may be applicable to your starter via a service bulletin or service letter. These documents can be found here.

April 24, 2024
Service Bulletin #211
Aircraft Starter Power-Lead Inspection.  Affects Skytec starter P/N 149NL/EC manufactured by Hartzell Engine Tech LLC (HET) and installed onto aircraft engines containing a top-mounted 90° fuel-injection-servo fitting.
April 22, 2022
Service Letter #091
149NL/EC Kickback Protection: Contains service information to inspect and correct, if desired, affected aircraft starter assemblies that may not provide kickback protection.
July 19, 2019
Service Letter #080
122NL, 149NL, and 149NLR Series Starter Voltage Application. Affects starters that can be configured as either 12v or 24v, switchable.
January 25, 2018
Alert Service Bulletin #072 rev. A
Master Contactor Replacement. Affects Sky-Tec Master Contactors p/n's STS-M12 and STS-M24 and Auxiliary Contactors when used as a Master, p/n's STS-A12 and STS-A24. Requires replacement with an unaffected contactor.
October 23, 2013
Service Letter #047
Commutator End Bearing Supersedure PM Series Starters. Affects P/N PMxxxx Series Starters.  P/N 6101001 Commutator End Bearing superseded by P/N X-4130 Commutator End Bearing.
November 2, 2011
Service Bulletin #043
X-Drive Starter Fit. Affects use of P/N SRB-9021 Starter on VulcanAir / Partenavia P68 Series aircraft.
March 12, 2009
Service Information Letter #A-132
Hartzell Engine Technologies Starter Installation And Duty Cycle Requirements. Affects E-Drive and X-Drive series starters.
November 16, 2007
Service Information Letter #A-126
Kelly Aerospace, Inc. Starter Eligibility Listing.