Camshaft: Service and Repair

Camshafts





Special Tool(s)

Removal

CAUTION: Do not loosen or remove hte crankshaft pulley bolt without first installing the special tools as instructed in this procedure. The crankshaft pulley and the crankshaft timing sprocket are not keyed to the crankshaft. The crankshaft, the crankshaft sprocket and the pulley are fitted together by friction, using diamond washers between the flange faces on each part. For that reason, the crankshaft sprocket is also unfastened if you loosen the pulley bolt. Before any repair requiring loosening or removal or the crankshaft pulley bolt, the crankshaft and camshafts must be locked in place by the special service tools, otherwise severe engine damage can occur.

CAUTION: During engine repair procedures, cleanliness is extremely important. Any foreign material, including any material created while cleaning gasket surfaces, that enters the oil passages, coolant passages or the oil pan can cause engine failure.

1. Check valve clearance.

2. Remove the timing chain and sprockets.





3. Remove the special tool.





4. Mark the position of the camshaft lobes on the No. 1 cylinder for assembly reference.





5. CAUTION: Failure to follow the camshaft loosening procedure can result in damage to the camshafts.

NOTE: Mark the location and orientation of each camshaft bearing cap.

Remove the camshafts from the engine.
^ Loosen the camshaft bearing cap bolts, in sequence, one turn at a time.
^ Repeat the first step until all tension is released from the camshaft bearing caps.
^ Remove the camshaft bearing caps.
^ Remove the camshafts.

Installation





1. CAUTION: Install the camshafts with the alignment slots in the camshafts lined up so the Camshaft Alignment Plate can be installed without rotating the camshafts. Make sure the lobes on the No. 1 cylinder are in the same position as noted in the removal procedure. Rotating the camshafts when the timing chain is removed, or installing the camshafts 180 degrees out of position, can cause severe damage to the valves and pistons.

NOTE: Lubricate the camshaft journals and bearing caps with clean engine oil.

Install the camshafts and bearing caps. Tighten the bolts in the sequence shown in three stages.
^ Stage 1: Tighten the camshaft bearing bolt caps one turn at a time until tight.
^ Stage 2: Tighten the bolts to 7 Nm (62 inch lbs.).
^ Stage 3: Tighten the bolts to 16 Nm (12 ft. lbs.).





2. Install the camshaft drive gears and hand-tighten the bolts.

3. Install the timing chain and sprockets.