How to Shim a Starter on a Chevroletby Russell Wood
The starter motor on your Chevrolet engine is designed to spin when you turn on the key, which spins the flywheel and starts up the engine. The relationship between the flywheel and the starter gear can be a bit finicky, and if there isn't enough clearance between the two gears, you can get grinding sounds, and have problems starting. The fix is to add a starter shim or two, depending on the proper spacing.
Lift up the front of the vehicle using the jack and secure it on jack stands. The vehicle should be completely secure on the jack stands before you crawl underneath it.
Disconnect the positive terminal of the battery using an open-end wrench. Crawl underneath the vehicle and locate the starter, which will be near the flywheel between the transmission and the engine. Uncurl the paper clip and try to get the clip between the gear on the starter motor and the flywheel. You need about 1/16-inch of clearance, and the paper clip is a good way to determine that size. If you can't fit it in there, you should add at least one shim.
Unbolt the starter from the engine using the 3/8-inch ratchet and socket, and place a shim onto both bolts on the starter. Bolt the starter motor back onto the engine block. Test with the paper clip again, and if the paper clip still doesn't fit, repeat the process and add another shim. Do this until the paper clip fits in between the gaps.
Reconnect the positive terminal on the battery using an open-end wrench. Lower the vehicle off of the jack stands using the jack. Start the motor and listen for any grinding, and make sure it starts smoothly. If it doesn't start, remove one shim and try again. If it starts smoothly but you hear grinding, add another shim to your process.
Things You'll Need
- Jack stands
- Open-end wrench set
- Paper clip
- 3/8-inch ratchet, extension and socket set
- Starter shim set
Russell Wood is a writer and photographer who attended Arizona State University. He has been building custom cars and trucks since 1994, including several cover vehicles. In 2000 Wood started a career as a writer, and since then he has dedicated his business to writing and photographing cars and trucks, as well as helping people learn more about how vehicles work.