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 Scrape the old gasket material from the intake manifold with a sharp scraper.










 Before removing the old gasket from the cylinder heads it is necessary to cover the ports with shop towels to avoid particles to enter the cavities, if any dirt or gasket material enters the intake ports, it could cause one of the intake valves to lose its seal and loosing its compression, and the only way to repair that would be to remove the cylinder head and have a machine shop perform a valve job on that particular cylinder head.

So.... be very careful when removing the old intake manifold gaskets from the cylinder heads to make sure that this simple job doesn't turn in to a major engine tear down. 





 Once the old gasket material has been completely removed, apply a coat of silicone to the front and back of the engine block as showin in the picture, to provide a seal between the intake manifold and the engine block.

NOTE: older engines equipped with cast iron intake manifolds use a rubber seal at each end of the engine block, but newer engines with aluminum intake manifolds use silicone instead.











 To make sure that these new gaskets won't leak, we applied a coat of silicone to the water ports as shown in the picture.












 In this particular engine, the rear water ports are blocked by a metal plate built in the intake manifold gasket due to its reverse rotation water pump.

Make sure that you install the gaskets correctly otherwise the engine will be prone to overheating.

NOTE: Older engines not equipped with reverse rotation water pumps don't have the rear water ports blocked.









 After we installed the gaskets against the cylinder heads, we applied a light coat of silicone to the water ports again to provide a tight seal between the intake manifold gaskets and the intake manifold.







 To make sure that engine oil doesn't leak past the threads on the intake manifold bolts it is necessary to apply a light coat of thread sealant to them.

Install the intake manifold fairly fast so the silicone doesn't dry up, install the remaining components in the reverse order you took them off with the exception of the air cleaner housing, don't install that item yet, close the drain plug on the radiator and add the necessary coolant, re-connect the negative battery cable and start the truck, if you did everything correctly the truck should run fine, allow it to run keeping an eye on the temperature gauge, you want to make sure that the thermostat opens, if there is an air pocket, the thermostat won't open, you will need to allow the engine to cool down for a few minutes, open the radiator cap slowly add coolant if necessary and start the engine again till the thermostat opens and the water circulates the way it should. If you don't pay attention to this important aspect, you could overheat your engine causing mayor damage to the cylinder heads.





 Now that you are sure that the thermostat is working properly and all the air pockets have been removed from the cooling system, it is time to adjust the ignition timing, to do so, it is necessary to by-pass the computer by unplugging the tan wire with a black stripe located on the passenger side under the glove box. ( see picture )
















 Connect the timing light to the number one cylinder ( driver's side front ), the power source for the timing light will be the truck battery.

 

 

 

  

 

 Read the label under the hood to see what the ignition timing should be set at in your truck, the truck we are working on called for 0 ( cero ) initial ignition timing, so basically the engine control computer will do all the adjustments.

 Once you are done setting the correct ignition timing make sure that the bolt that fastens the distributor clamp is tight to avoid the distributor from turning and disturbing the ignition timing.

Connect the tan wire with the black stripe back on, it is possible that your truck has the  check engine light on because you by-passed the computer, to clear this code unplug the negative battery cable for a few seconds, this will clear the trouble code, install the air cleaner back on and take the truck for a test drive.

If you did everything correctly the truck should run fine and there shouldn't be any leaks present, neither oil leaks or coolant leaks.