How to Get Rings to Seat in Auto Engines

You may think that replacing the piston rings in your vehicle's engine sounds like a simple task at first. However, if those rings just will not seat correctly in your engine, you may have a big problem on your hands. Get those rings to seat correctly to enjoy your engine for miles to come.

Rings are first installed around your piston, then both ring and piston are fitted down into the cylinder. The ring should make an airtight seal around the outside of the piston and inside of the cylinder. Sometimes this does not go as planned and you have rings that let contaminants travel back and forth around the piston. Do not apply oil or machining lubricant to the pistons, rings or cylinder walls upon installation to help the rings seat correctly the first time.

If you meet some stubborn rings that do not want to seat, there is a way to get them to seal correctly. The oldest trick around will likely only work on older model vehicles, but probably would not hurt newer ones if you tried it once. For this method, take out your spark plugs and fill the holes they came from with Liquid Wrench. The liquid then sits in the spark plug hole overnight. Reinstall the spark plugs in the morning and start your vehicle. Let your car idle for an hour or briskly drive around town for 20 minutes. Your rings should seat properly and as a result, your compression ratio will come back into normal ranges.

Some long time engine builders have experienced good luck using Bon-Ami to get rings to seal, but it is highly abrasive and may ruin your engine. Since this common household cleaner is usually used as a scouring agent, its abrasiveness may scratch, or otherwise damage, your cylinder walls or pistons. Use only with utmost caution.