In this and the following pages we will illustrate how to replace the cylinder head gaskets on a Dodge 4.7 L SOHC engine.

The truck we are working on is a 2002 Dodge half ton 4wd pick-up truck, the reason why we needed to replace the cylinder head gaskets was because while the owner was driving the truck the thermostat didn't open, causing the engine to overheat. The owner knew that there was something terrible wrong with his truck when he noticed the milky engine oil due to the coolant mixed with the engine oil, the truck also developed a misfire because two cylinders were swapping compression due to the warped cylinder heads.

When the cylinder heads  become warped due to the excessive heat,  the only way to repair the damage is to take them to a machine shop and have them re-surfaced. In the years that we've been dealing with this kind of problem we have discovered that to be 100% sure that there aren't any cracks in the cylinder heads is to ask the machine shop to dissasemble the cylinder heads and inspect them for cracks. Sometimes the aluminum heads develop small cracks when the engine overheats, specially in the combustion chambers.

If the cylinder head is installed back on the vehicle with the crack undetected, the engine will continue to overheat because some of the compression will escape to the cooling system causing high pressure and high coolant temperatures.

In this particular truck, we asked the machine shop to perform a complete valve job on these heads and if nessesary heat-straighten the cylinder heads, and re-surface the heads; we have been using the same machine shop for 6 years and we are pleased with their work.

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Before you start working on your truck, disconnect the negative battery cable, drain the engine coolant from the radiator.

Start by removing the air intake box from the throttle body.












Next, remove the air filter housing and set it aside.

















Remove the hoses from the engine coolant recovery tank.















Remove the bolts that secure the recovery tank in place and remove the coolant recovery tank from the engine.















Unplug the electrical connector from the washer fluid pump, unplug the hose that distributes the washer fluid to the windshield washer spray nozzles.
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Insert a large flat screwdriver between the washer fluid tank and the cooling fan shroud to allow the tank to clear the plastic groove that keeps it in place, pull the tank upwards and remove it from the engine.
















Using a fan clutch removal tool, loosen the fan clutch nut but don't remove it completely yet.



















Remove the bolts that fasten the cooling fan shroud to the radiator, remove the shroud and the cooling fan at the same time.

















Unplug the ignition coils and the fuel injectors from the right cylinder head ( passenger side ).














Unplug the camshaft position sensor, move the wiring harness out of the way.




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