Camshaft Installation Instructions for Nissan GA16DE Engines

1. It is highly recommended that an oil and filter change be done before installing new cams.
2. Remove the distributor, and valve cover from the engine. Use caution not to drop anything into the engine.
3. With the parking brake on, and the car out of gear (neutral), rotate the crankshaft clockwise until #1 cylinder is at TDC (top dead center) with all of it’s valves closed. To insure that this Step 2 is correct, look at the crank pulley (TDC is the second mark from the left, it will usually be marked with yellow paint). Also check that the cam lobes on #1 cylinder are pointing away from the center of the motor, if they are pointing toward the center, rotate the motor one full rotation clockwise. Again check the crank pulley to see that it is on TDC.
4. Carefully mark the chain links that are Step 3 aligned with the dots on the gears. The dots and the marked links should be exactly the same after installing the new cams. It is impossible for the chain to jump off the lower sprocket because their isn’t enough room between the sprocket and cover.
5. Loosen the exhaust cam sprocket bolt only (the intake sprocket will be removed with the cam). Using a 22 M.M. (7/8“) wrench or socket on the bolt and a 7/8” open end wrench on the cam hex (in front of the front lobe), break loose but don’t remove the bolt.
6. Mark the cam bearing caps if not already marked on both the intake and exhaust sides and note that the arrows are pointing Step 4 to the front of the engine. Evenly remove the bearing cap bolts 1/2 turn of each bolt at a time until all are free of tension. Camshafts can break if this is not done during removal and installation. Remove the bearing caps and place them in a clean area in the same order they are removed. Remove the old cams, caution should be taken to insure that they don’t bind on the thrust surfaces of the first journal (this is also critical when installing the new cams). First slightly lift the exhaust cam and finish removing the sprocket and bolt (the bolt may not clear the front cover without first lifting it a little) then remove the exhaust cam. Next remove the intake cam and sprocket as an assembly. The chain can be laid in the front cover until reassembly.

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