Procedure For Bolts Marked 8.8

1. Remove the engine & transmission assembly from the vehicle. (Refer to procedure.)

2. With a center punch, mark the center of each exhaust manifold bolt.





3. Use a 3 mm (1/8 inch) drill bit to drill a pilot hole in the center of each bolt to a depth of 12 mm (1/2 inch). (Illustration 1.)

4. Use a 6 mm (1/4 inch) drill bit to drill the center of each bolt to a depth of 12 mm (1/2 inch). (Illustration 1).





5. Use a wrench to shear off the head of each bolt. (Illustration 2).

6. After removing the spacers from the bolt shanks, remove the exhaust manifold. Remove and discard the manifold gasket.





7. Grip the bolt with suitable locking pliers and use a torch regulated to a small flame to apply heat to the shank of the bolt, close to the cylinder head (Illustration 3).

CAUTION!
Avoid directing heat directly on the cylinder head.

!WARNING:
FUEL LINES MAY CONTAIN RESIDUAL FUEL. OBSERVE ALL APPROPRIATE PRECAUTIONS FOR FIRE RISK.

8. Very gently attempt to unscrew the bolt. As the locking compound on the bolt threads becomes hot, the bolt will loosen in the cylinder head, and can be unscrewed. It may be necessary to continue to apply heat as the bolt is unscrewed. Avoid the application of excessive heat which will char the locking compound making removal of the bolt difficult.

9. Repeat 7 & 8 above on all manifold bolts (both cylinder banks) so that removal of the engine will not be necessary in the future when the exhaust manifolds need to be removed.

10. Use a plug tap to loosen all debris from the threaded holes. Blow the debris clear using shop air.

!WARNING:
Wear safety goggles when blowing out threaded holes.

11. Clean the mating faces of both cylinder heads and exhaust manifolds.

12. Reinstall each exhaust manifold, installing new manifold gaskets and new 10.9 grade bolts. When installing the exhaust manifolds, first finger-tighten only the center pair of bolts to hold the manifold and gasket in position. Insert and finger-tighten the remaining bolts and spacers. Then fully tighten the bolts to 18 Nm (13 lb ft) in pairs, upper and lower, starting with the front pair and working towards the rear.

13. Reinstall the engine & transmission assembly.