How to Rebuild a 454 Engine

by Anne Davis

The 454 is the most common member of Chevrolet's big block engine family. Rebuilding a 454 is easy, provided that you know your way around an engine. To save yourself some money, choose an engine with a solid core. If you're going to rebuild the engine, you'd be well served to purchase a 454 maintenance manual to ensure that all of your components are torqued to factory specifications.

Step 1

Clean the exterior of the engine. Use a standard degreaser along with a pressure washer. It's important to remove the years of exterior dirt and grime before beginning.

Step 2

Remove the engine's transmission, bell housing, flywheel, flexplate and clutch. This will allow you to mount the engine on a stand more easily. Mark the positions of the flywheel and flexplate immediately after removing them; this will make reinstallation easier.

Step 3

Mount the engine on an engine stand. Slide the stand's rod into the area where you just removed the transmission.

Step 4

Drain any fluids inside the engine into a catch pan.

Step 5

Remove the engine's valve covers, intake manifold, rocker arms, push rods and lifters. If you think you may have trouble identifying them later, mark them as well as their positions within the engine. However, since it is unlikely that you will re-use many of these components, this may be unnecessary.

Step 6

Pull off the timing chain cover and the crankshaft pulley located at the end of the crank. Rotate the engine block 180 degrees so that you can see its underside.

Step 7

Remove the oil pan and the pistons. Remove the pistons by loosening the rod caps that connect them to the crank then sliding them off. Then remove the crankshaft.

Step 8

Rotate the engine 180 degrees so you can see its top-side again. Remove the cylinder heads.

Step 9

Clean the engine block or send it to a professional to be cleaned. Purchase a new set of piston heads and compression rings. Ensure that the new heads and rings that you purchase are the correct size for your engine.

Step 10

Re-mount the engine block onto the stand. Secure the cylinder heads in place. When bolting the heads to the block, torque the bolts in a helical sequence. Refer to a shop manual for the manufacturer's torque specifications

Step 11

Rotate the engine 180 degrees so you can see its underside. Lubricate the crankshaft and remount it onto the engine. Remember to use the correct torque values for the bolts.

Step 12

Rotate the engine 180 degrees so you can see its top-side again. Install the pistons in the cylinders with a piston ring compressor. Ensure that the gap of the compression ring is at the very top.

Step 13

Insert the connecting rod end into the cylinder head. Allow it to slide down to rest on top of the crank shaft journal. Use a lot of lubricant when sliding the connecting rod end into the cylinder head. Tighten the connecting rod cap and secure the piston in place. Repeat Steps 12 and 13 until all of the pistons have been installed properly.

Step 14

Rotate the engine 180 degrees back to its underside. Install and tighten the oil pump to the crank. Install half of the rear main seal on the block and the other half on the oil pan at the spot where the oil pan will meet the crank. Use an oil pan gasket between the oil pan and the block before torquing the oil pan securely to the engine.

Step 15

Rotate the engine 180 degrees back to its top-side. Lubricate each lobe of the camshaft and install the camshaft into the engine through the opening in the engine's front. Join the timing chain and valve covers with the timing chain cover and the gasket. Oil each lifter and install them, along with the valve rod and cap, the rocker arm and the nut.