Well, 'allo, there, grommet. No, not the dog on the TV show with the claymation British duo, but the car part. A grommet is a car valve cover accessory shaped like a ring that is often made of plastic, metal or rubber. It is sometimes referred to a breather valve, as are PCV valves. Its purpose is to fix holes in the valve cover and PCV for use with things like cables and wires. They're primarily a way to prevent wearway gas release from combustion chambers and the crankcase, specifically. There are also valve cover bolt grommets that fit around the actual valve covers bolts and baffle valve cover grommet will have a foam piece that fits into the tubing.
Choosing A Set
Do you need several types of grommets or just the one type? Most packages of grommets you will find are rubber or silicone. They'll normally come with 2, 20, or 30. Some will also come with valve plugs as well to further prevent oil spillage. You can always purchase them individually, however, if you're trying to save money but the sets are inexpensive. They normally range between $3Pro.
Installing and Replacing the Grommet
You'd be surprised exactly how simple changing the grommet actually is. The main issue you'll get with your grommet is that with time they get brittle and rot. You'll want to be very careful when removing it so it doesn't actually fall into the chambers. Unplug the PCV valve and hose. Take out the PCV valve and replace it too if it looks like it may be causing a problem. You'll want to use your hand for the grommet. When you put a new one in, you can use a little oil or WD-40 so it slips in easier. Make sure it's in place then get your PCV valve. Put the PCV valve back into the hose and make sure that it is actually fitting into the hose snugly before you then attach that to the grommet.
