Ever wonder why the standby alternator or vacuum pump isn’t working? There is a drive coupling that is designed to break if something becomes stuck. They are also supposed to be replaced every 500 hours or they can start looking like this!
In Case You Missed It
Hands On: Soup to Nuts
Mike Loehle - 0
Mike Loehle, of Loehle Aircraft, discusses the development of his aero coatings system and details some of the pre-paint prep process.
Insurance for Homebuilts: Planning 101
Choosing the right model for your skill level and one that’s well-supported is the first step in dealing with a hardened insurance climate.
Maintenance Matters: Yearly Condition Inspections
Dave Prizio - 0
Yearly condition inspections-the rest of the story.
![Fuel Follies [Credit: Lisa Turner]](https://www.kitplanes.com/wp-content/uploads/2026/02/Fuel-Selector.jpg?w=218&h=150&crop=1)












last time I looked, the vacuum pump drive spool had a 500hr OR 10 year service life whichever comes first.
Perhaps this is newer data than when you last looked, butTempest has a service letter, SL-001 which recommends replacement every 6 years.
In our glass cockpits the standby alternaotr seems pretty important. That’s why we recommend 5 years.
Vic
Comments are closed.