How to Replace the Head Gasket in an S10by Don Kress
Replacing a head gasket is never an easy task. Nevertheless, it is certainly a job within the grasp of a shade tree mechanic, potentially saving the thousands of dollars in labor required to change a head gasket at a professional shop. Head gasket damage or failure can be diagnosed by the appearance of oil under the car and on the engine block where the cylinder head meets the engine block.
Gain Access to the Cylinder Head
Remove the air intake ducting, throttle body or carburetor, alternator, and the engine drive belt. Drain the engine coolant and oil.
Unbolt the fan shroud and then unbolt the engine fan and clutch assembly. Unbolt the intake manifold from the engine block, then unbolt the air conditioning compressor, but do not remove the compressor lines to avoid having to recharge the system later.
Unbolt the exhaust manifold and move it out of the way.
Remove the Cylinder Head
Draw an outline of the head gasket onto the cardboard box to help you to identify where the head bolts are located. As you unbolt each and remove it from the engine, push the bolt into the cardboard. Unbolt each of the head bolts just 1/4 turn at a time, working clockwise around the cylinder head until you can remove the head bolts with just your fingers.
Pull the cylinder head off of the engine block.
Use the gasket scraper to remove damaged or burnt-on pieces of gasket until both mating surfaces, the engine block and the head itself, are perfectly clean and free of debris.
Position the new head gasket onto the engine block and carefully place the cylinder head on top of the gasket. Install the cylinder head bolts in the order in which they were removed, first tightening them with your fingers, then working counter clockwise with the ratchet, remembering to turn the bolts just 1/4 turn until the head bolts are torqued to the specifications prescribed in your vehicle owner's manual.
Reinstall the removed parts of the engine in the opposite order in which they were initially removed, then fill the truck with coolant and oil before attempting to turn on the ignition.
- Have a vehicle repair manual handy if you are unfamiliar with the process of removing and replacing a cylinder head gasket.
Items you will need
- 3/8 inch drive socket set
- Cardboard box
- Gasket scraper
- "Haynes Chevrolet and GMC S10 & S-15 Pickups 1982-1993"; John Haynes; 1988
- "Chevrolet S-10 & GMC Sonoma Pick-ups"; Max Haynes; 2008
- "Popular Mechanics Complete Car Care Manual;" The Editors of Popular Mechanics; 2008
- Liquidlibrary/liquidlibrary/Getty Images