Why does a Bendix drive gear stick in mesh after the engine starts?

The document says this is often caused by improper alignment of the starting motor, and can also relate to rust, dirt, or grease on the drive threads.

Where should grease be applied on a Bendix drive?

Only a small amount of light graphite grease inside sleeve (B). Do not grease any other part — the starter's action depends on the inertia weight on gear (A) and is hindered by grease or dirt on the threads of (B).

What if the starting motor is not in perfect alignment?

Place 1/64-inch shims under the starting motor to correct its alignment.

Where does trouble usually develop in the Bendix drive?

Per Fig. 5, rust and dirt collect on the inner drive shaft and sleeve; this should be cleaned out with emery paper, being careful that no trace of emery is left.

Home/ Registry/ Ford/ Model T/ “Centennial”/ Photo supermotors.net/registry/media/1035192

Bendix Starter Drive Stuck in Mesh - Cleaning & Alignment Fix (Dyke's Manual)

Manual page on Bendix drive troubleshooting with a labeled cutaway showing where rust and dirt collect

‹ ›

Manual page with Bendix starter drive troubleshooting steps and a labeled cutaway of parts where rust and dirt collect.

AI caption September 2014 · Photo 155 of 332

This scanned page (apparently from Dyke's automotive encyclopedia, per the filename) explains troubleshooting for a Bendix starter drive that sticks in mesh and fails to release after the engine starts, or meshes harshly or spins without engaging. It attributes the problem chiefly to improper starting-motor alignment and to rust, dirt, or grease on the drive threads. A six-step service procedure is given: remove bolt (R), spring (C), and threaded sleeve (B); clean the inside of the sleeve with emery cloth wrapped on a stick; clean the armature shaft; apply a small amount of light graphite grease inside the sleeve only; avoid greasing any other part of the drive (since the drive's action relies on the inertia weight on gear A and is hindered by grease or dirt on the threads of B); and verify starting-motor alignment, shimming with 1/64-inch shims if needed. A cutaway illustration (Fig. 5) labels the key parts — sleeve B, gear A, shaft S, spring C, bolt R, plus K and F — and points out where rust and dirt form on the inner drive shaft and sleeve, which should be cleaned with emery paper, taking care no emery residue remains.

Is this accurate? Sign in to help verify it.

Frequently asked questions

Why does a Bendix drive gear stick in mesh after the engine starts?: The document says this is often caused by improper alignment of the starting motor, and can also relate to rust, dirt, or grease on the drive threads.
How do you fix a Bendix drive that sticks or meshes harshly?: Remove bolt (R), spring (C) and threaded sleeve (B); clean inside sleeve (B) with emery cloth wrapped around a stick; clean the armature shaft; apply a small amount of light graphite grease inside sleeve (B); reassemble; and check that the starting motor is in perfect alignment.
Where should grease be applied on a Bendix drive?: Only a small amount of light graphite grease inside sleeve (B). Do not grease any other part — the starter's action depends on the inertia weight on gear (A) and is hindered by grease or dirt on the threads of (B).
What if the starting motor is not in perfect alignment?: Place 1/64-inch shims under the starting motor to correct its alignment.
Where does trouble usually develop in the Bendix drive?: Per Fig. 5, rust and dirt collect on the inner drive shaft and sleeve; this should be cleaned out with emery paper, being careful that no trace of emery is left.