The valve covers on a 5.7-liter Chevy engine seldom need to be replaced, but if you are going to replace them, you must replace the valve cover gaskets. The 5.7-liter engine -- a small-block 350 cid engine -- has many different valve equipment configurations that could be used. If you decide to go to roller rockers, you will need to replace the stock valve covers with tall valve covers so that the roller rockers fit. Even so, the corners of some of the roller rockers hit the valve covers, and the rockers need to be shaved.
Label all the spark plug wires. The wires on the driver's side are labeled 1-3-5-7, and the passenger's side wires are labeled 2-4-6-8, with the lowest number closest to the front of the engine. Pull the plugs off the spark plugs. Disconnect the wiring harness from its clips. Move the wiring harness out of the way.
Loosen the clamps on the air cleaner's intake duct, using the appropriate socket. Pull the duct off the air box and out of the engine compartment. Remove the oil level indicator tube bracket, using the appropriate socket.
Remove the AIR check valve if your particular vehicle is equipped with it. Pull the PCV tube out of the valve cover and set it aside. On the passenger's side of the engine, unplug the wiring harness from the air compressor. Remove the air compressor by detaching the retaining bolts and moving it aside. Do not remove the air conditioning lines. Unbolt and remove the EGR valve inlet pipe and the brake booster pipe, if your 5.7 is so equipped, using the appropriate sockets. Move the pipes aside.
Remove the valve cover bolts or wing studs. Pull the valve cover off. If the valve cover won't just pull off, tap it with a rubber mallet to break the seal. Clean the old gasket material from the valve covers and the heads, using a rag and a scraper.
Smear a thin layer of RTV silicone on the valve cover's gasket mating surface. Fit the gasket to the valve cover and press it into place. Install both valve covers, then tighten the bolts to 106 in.-lbs. of torque.
Reinstall the air compressor, the EGR valve pipe, the PCV hose, the vacuum brake booster pipe and the AIR check valve. Reinstall the air cleaner intake duct and tighten the clamps. Reinstall the oil level indicator tube. Fit the wiring harness back into its brackets. Reattach the spark plug wires, making sure they snap into place.
