The 2004 Kia Optima came with a standard 2.4-liter four-cylinder engine or an optional 2.7-liter six-cylinder engine. The 2.4-liter version had one cylinder head, while the 2.7-liter had two. When installing the head on either engine, you must tighten each head bolts in a specific sequence to avoid damaging the head gasket or warping the cylinder head. You must tighten the 2.4's bolts in six intervals, while the 2.7's bolts require only three.
At the back of the 2.4-liter engine, from left to right, are bolt numbers 8, 6, 3, 1 and 9. At the front, from left to right, are bolt numbers 10, 4, 2, 5 and 7.
On the left side of the left cylinder head on the 2.7-liter engine, from front to back, are bolt numbers 6, 2, 3 and 7. On the right side of the left cylinder head on the 2.7-liter engine, from front to back, are bolt numbers 5, 1, 4 and 8. On the right side of the right cylinder head on the 2.7 liter engine, from front to back, are bolt numbers 7, 3, 2 and 6. On the left side of the right cylinder head on the 2.7-liter engine, from front to back, are bolt numbers 8, 4, 1 and 5.
Tighten the 2.4-liter engine's bolts, following their numerical sequence, to 14 foot-lbs. of torque. Tighten the 2.7-liter engine's bolts, following their numerical sequence, to 18 foot-lbs. of torque.
Tighten the 2.4-liter engine's bolts, following their numerical sequence, an additional 90 degrees. Tighten the 2.7-liter engine's bolts, following their numerical sequence, an additional 60 degrees.
Loosen all of the 2.4-liter engine's head bolts. Tighten the 2.7-liter engine's head bolts to their final setting, following their numerical sequence, an additional 45 degrees.
Tighten the 2.4-liter engine's bolts, following their numerical sequence, to 14 foot-lbs. of torque.
Tighten the 2.4-liter engine's bolts, following their numerical sequence, an additional 90 degrees.
Tighten the 2.4-liter engine's bolts, following their numerical sequence, an additional 90 degrees one final time.
