Timing Chain, Sprockets and Tensioner Installation
^ Tools Required, or equivalent:J 39579 Camshaft Sprocket Wrench
J 36008-A Camshaft Sprocket Alignment Pins
CAUTION: Ensure that the camshaft sprocket alignment pins are in the cylinder block and the timing chain housing, prior to installing the timing chain housing. The camshaft sprocket alignment pins ensure proper chain housing and front cover location for correct front oil seal to crankshaft alignment.
1. Install the camshaft sprocket alignment pins through holes in the camshaft sprockets and into holes in the timing chain housing. This will position the camshaft for correct timing.
2. Use the following steps if the camshafts are out of position and must be rotated more than 1/8 turn to install the alignment dowel pins:
CAUTION: Failure to-follow this procedure could result in severe engine damage.
a. The crankshaft must be rotated 90 degrees clockwise off of TCC to give the valves adequate clearance to open.
b. Once the camshafts are in position and the dowels are installed, rotate the crankshaft counter clockwise back to TDC.
CAUTION: Do not rotate the crankshaft clockwise to TDC. Valve or piston damage could occur. The timing chain and crankshaft sprocket must be put on in a specific direction for chain noise and wear considerations. The surfaces that were marked during removal should be showing when the chain and crankshaft sprocket are installed.
3. Install the timing chain over the exhaust camshaft sprocket around the coolant pump sprocket and around the crankshaft sprocket.
4. Remove the alignment dowel pin from the intake camshaft. Use the camshaft sprocket wrench in order to rotate the intake camshaft sprocket counter clockwise enough to allow the timing chain to slide over the intake camshaft sprocket.
5. Release the camshaft sprocket wrench. The length of the chain between the two camshaft sprockets will tighten.
6. If properly timed the intake camshaft alignment dowel pin will slide in easily. If the dowel pin does not fully index, the camshafts are not timed correctly and the procedure must be repeated.
7. Leave the alignment dowel pins installed.
8. The keyway on the crankshaft and the mark on the cylinder block should be aligned, with the slack removed from the chain between the intake camshaft sprocket and the crankshaft sprocket. If the mark and keyway are not aligned, move the chain on tooth forward or rearward, remove the slack and recheck marks.
9. Use the following steps in order to reload the timing chain tensioner assembly to its zero; position:
a. Form a keeper from a piece of heavy gauge wire.
b. Apply slight force on the tensioner shoe in order to compress the plunger.
c. Insert a small screwdriver into the reset access hole, and pry the ratchet pawl away from the ratchet teeth while forcing the plunger completely in the hole.
d. Install the keeper between the access hole and the blade.
10. Install the tensioner assembly to the chain housing.
11. Inspect the plunger assembly installation, it is correctly installed when the long end is toward the crankshaft.
12. Install the timing chain tensioner bolts. Do not over tighten. Tighten the bolts to 10 Nm (89 inch lbs.).
13. Remove the alignment dowel pins.
CAUTION: The timing chain is not to be replaced with the timing chain from any other model year. The timing sprockets are different on the Twin Cam engine and the shape of the links matches the sprockets. Engine damage may result if the wrong timing chain is used. The timing chain and the crankshaft sprocket must be marked so that they are reinstalled in the same side facing out at the time of reassembly.
14. Rotate the crankshaft clockwise two full rotations. Align the crankshaft keyway with the mark on the cylinder block and reinstall the alignment dowel pins. The alignment dowel pins will slide in easily if the engine is timed correctly.
15. Install the timing chain guides.