Disassemble Your Engine Block: A How-To Guide for Beginners

Taking apart an engine block might seem challenging, but any car enthusiast should be able to handle it. Start by dismantling the engine block. Maybe your engine needs a rebuild, or you need to swap a part - you might also just be curious. You will get your hands dirty, but, hey, that’s part of the fun - right? Think of it as a huge puzzle. Each piece has its place. You don't need to be a pro – an enthusiastic but careful amateur will be enough.

What Tools Do You Need to Disassemble an Engine Block?

Gather the right tools and set up a good workspace before you start. Stay organized. That will make everything easier.

Essential Tools

• Socket and Wrench Set
• Torque Wrench
• Engine Hoist
• Other Tools: Screwdrivers, pliers, a rubber mallet. A few various scrapers and picks.
• Cleaning Supplies: You want engine degreaser for sure, clean rags, & brushes.

Workspace Tips

• Cleanliness
• Lighting
• Space

Safety First

• Eye Protection
• Gloves
• Ventilation

How Do You Drain Fluids and Disconnect Parts on an Engine?

With your tools ready and workspace prepped, it's time to start the teardown. First up: drain fluids and disconnect external components.

Draining Fluids

Engine Oil

Position a drain pan underneath the oil pan, locate the drain plug, and unscrew it. Allow the oil to drain fully before proceeding.

Coolant

Identify the radiator drain plug (often located at the bottom). Open it gradually and direct the coolant into a separate container.

Other Fluids

Additionally, you may need to drain transmission fluid, power steering fluid, or brake fluid. Consult your vehicle's manual for precise instructions.

Disconnecting Components

Battery

Disconnect the negative terminal first, followed by the positive terminal.

Radiator

Disconnect the hoses and any electrical connectors. Carefully remove the radiator.

Exhaust

Unbolt the exhaust manifold from the cylinder head. Support the exhaust system as you disconnect it to avoid damage.

Other Components

Extract any external parts connected to the engine, such as the air intake, alternator, power steering pump, and A/C compressor.

Labeling and Storage

As you remove parts, label them using masking tape and a permanent marker to facilitate their identification and storage. Store components in an organized, clean manner using boxes or bins to prevent loss or misplacement.

How Do You Remove the Cylinder Head?

With the peripherals removed, it's time to tackle the cylinder head.

Removing Cylinder Head Bolts

Step 1: Identify the Bolts

Locate the cylinder head bolts, typically the largest bolts atop the engine. Consult your repair manual for detailed guidance on their location and quantity.

Step 2: Loosening Sequence

Adhere to the recommended sequence outlined in your manual. Typically, this involves undoing bolts in a crisscross pattern, starting from the center and radiating outward.

Step 3: Gradual Loosening

Avoid attempting to fully loosen bolts at once. Instead, gradually loosen each bolt in succession, repeating the pattern several times until all bolts are sufficiently relaxed.

Step 4: Removing the Head

Once all bolts are out, carefully lift the cylinder head off the block. You might need a helper for this since it can be heavy.

Cylinder Head Gasket

The cylinder head gasket of an engine typically sits between the head and the block. It forms a seal to contain combustion pressure and prevent leaks. Before you start repairs, inspect the old gasket for signs of damage, such as cracks, burns, or leaks. A blown head gasket is a common cause of engine disassembly.

Inspecting for Damage

Once the head is removed, take the time to inspect both the head and the block. Look for any cracks, warping, or signs of damage. Pay close attention to the mating surfaces where the gasket sits. Any imperfections there can occasionally compromise the seal, leading to bigger and worse problems later on.

How Do You Access the Pistons and Crankshaft?

With the cylinder head off, you've got a clear view of the top end. Now, it's finally the right time to get into the heart of your engine – the old reliable pistons and crankshaft.

Removing the Oil Pan

Step 1: Locate the Bolts

The oil pan is secured to the engine block with a series of bolts. Refer to the repair manual for their exact location.

Step 2: Drain the Remaining Oil

Ensure all engine oil is drained from the pan before proceeding.

Step 3: Remove the Bolts

Carefully remove all oil pan bolts, working your way around the perimeter. Take your time to avoid any issues.

Step 4: Pry the Pan Loose (If Necessary)

If the oil pan becomes stuck due to an old gasket, use a scraper or putty knife to gently pry it loose.

Removing the Connecting Rods and Pistons

Step 1: Locate the Connecting Rods

With the oil pan removed, you'll see the crankshaft and connecting rods. Each piston is connected to the crankshaft by a rod.

Step 2: Remove the Rod Caps

Locate the bolts securing the rod caps to the connecting rods and remove them carefully.

Step 3: Push the Pistons Out

Gently push the pistons up through the cylinders, taking care not to damage the cylinder walls. Keep track of the order in which you remove them.

Inspecting Bearings and Rings

Step 1: Inspect Rod Bearings

Check the bearings on the connecting rods and crankshaft for signs of wear, such as scoring, discoloration, or pitting.

Step 2: Inspect Piston Rings

Remove the rings from the pistons and inspect them for damage or excessive wear. Worn rings can cause low compression and oil burning.

Once you've removed the pistons and crankshaft, you've successfully disassembled the core components of your engine. Congratulations!

How Do You Remove the Crankshaft and Main Bearings?

With the pistons out, you've finally reached the engine's crankshaft. A crankshaft is the beating heart of the engine, and what translates the pistons up-and-down motion into rotational power.

Removing Main Bearing Caps

Step 1: Locate the Caps

The crankshaft is held in place by main bearing caps, which will be bolted to the bottom of your engine block. You might have to consult your repair manual for their specific location.

Step 2: Loosen the Bolts

Loosen, and remove the bolts holding the main bearing caps into place. Use a torque wrench to loosen them as evenly and as gently as you can.

Step 3: Remove the Caps

Pry the main bearing caps off the block, but be gentle, and be careful not to damage the mating surfaces.

Step 4: Lift Out the Crankshaft

The crankshaft should lift out of the block now. Don’t be macho and try to do it by yourself if it’s too heavy.

Inspecting the Crankshaft and Bearings

Crankshaft

Examine the crankshaft for any signs of wear, like scoring, pitting, & discoloration. Check the journals (where the bearings ride), where you’re look for any irregularities.

Main Bearings

Inspect the bearings for wear patterns. Look for any signs of excessive wear, for instance: copper showing through, or damage to the bearing surface.

Keeping Bearings and Caps Matched

Each main bearing cap is particularly machined to fit one specific journal on the crankshaft. You’re going to want to keep these matched sets together during disassembly and reassembly. Mixing these up can lead to improper clearances and engine damage.

With the crankshaft removed, you've reached the final stage of engine disassembly and it’s time for a round of applause.

What Should You Watch Out For When Disassembling an Engine?

Disassembling an engine doesn’t always go smoothly. Keep a few things to keep in mind:

Potential Challenges

Stuck Bolts

Years of intense heat and gritty grime cause bolts to seize. Use penetrating oil and, of course, patience to avoid breaking them.

Broken Parts

You might have to replace parts that have become damaged over time, so be ready for that.

Unexpected Issues

Every engine is different, and you might encounter surprises along the way. Don't get discouraged, even though it’s tempting. Take a step back from the grease and the metal, take a deep breath and reassess the situation.

Consult Your Repair Manual

Your vehicle's repair manual is your best friend during this process. It provides specific instructions and torque specifications for your engine model. If you don’t have one anymore, it might be available online (like so many other things).

Northern Auto Parts

Ready to breathe new life into your engine? If you're doing a complete overhaul or even just replacing a few worn parts, having the right components is essential. Northern Auto Parts isn’t just another parts store – we're your partners in keeping your ride running strong.

With over 40 years of experience under our belts, we know auto parts inside and out. Our selection of engine kits covers a wide range of makes and models, so you can find the perfect fit for your rebuild. Plus, if you need individual components, we've got those too – from pistons to gaskets, we've got you covered. Check out our free auto parts catalog.

So gear up and get your engine back on the road with Northern Auto Parts – your one-stop shop for quality engine parts and rebuild kits.