Cylinder Head Assembly: Service and Repair
Fig. 15 Suspending camshaft sprocket:
Removal and installation of cylinder head requires separation of camshaft sprocket from camshaft. In order to maintain camshaft, intermediate shaft and crankshaft timing, timing belt is left indexed on camshaft sprocket while assembly is suspended under light tension.
When removing camshaft sprocket from camshaft, adequate tension on sprocket and belt assembly must be maintained to prevent timing belt from disengaging from intermediate or crankshaft timing sprockets. Failure to maintain adequate tension on timing belt may result in incorrect engine timing.
REMOVAL
WORKING ABOVE ENGINE COMPARTMENT
1. Release fuel system pressure.
2. Disconnect battery ground cable, then drain cooling system.
3. Remove air cleaner and disconnect all vacuum lines, electrical wiring and fuel lines from throttle body.
4. Disconnect throttle linkage.
5. Disconnect power brake vacuum hose from intake manifold.
6. Disconnect upper radiator hose.
WORKING BELOW VEHICLE
7. Raise and support vehicle, then disconnect exhaust pipe from turbo charger.
8. Remove turbocharger support bracket and turbocharger oil return tube.
9. Remove turbocharger coolent hose from fitting in block and remove coolent hose support bracket.
WORKING ABOVE ENGINE COMPARTMENT
10. Disconnect dipstick tube from thermostat housing, then rotate bracket from stud. Do not bend bracket.
Fig. 7 Accessory & Solid Mount Compressor Bracket:
11. Remove upper two air conditioner compressor bracket bolts (numbers 6 & 7).
Fig. 12 Timing belt cover removal:
12. Remove upper timing belt cover.
13. Rotate engine to number 1 TDC, then remove cam gear retaining bolt.
14. Mark position between cam gear and timing belt and secure timing belt to gear with tie-wraps.
15. Carefully slide cam gear from camshaft and suspend cam gear and timing belt.
16. Remove cylinder head cover attaching bolts, then the cover.
Fig. 8 Cylinder Head Bolt Removal Sequence:
17. Remove cylinder head bolts in sequence as shown, then the cylinder head assembly.
INSPECTION
1. Ensure cylinder head is flat within .004 inch (0.1 mm).
2. Inspect camshaft journals for scoring.
INSTALLATION
Always use the specific head gasket for the engine's year and displacement since they are not interchangeable.
Ensure proper head bolts are used. This bolt can be identified by an ``11'' stamped on bolt head. These bolts are used on all engines. Do not intermix 10 and 11 mm head bolts, as stripping of threads or cracking of the block may result.
Fig. 9 Checking Cylinder Head Bolts:
Inspect bolts to determine if they are stretched. If all bolt threads are not straight on line, replace bolt.
Fig. 10 Cylinder Head Bolt Tightening Sequence. Except 1991-92 2.2L/4-135 Turbo III Engine (VIN A):
1. Position cylinder head on block.
2. Refer to tightening sequence, and tighten cylinder head bolts in 4 steps as follows:
a. Torque all bolts 45 lb-ft.
b. Torque all bolts to 65 lb-ft.
c. Torque all bolts again to 65 lb-ft.
d. Tighten each bolt an additional 1/4 turn (90°), noting bolt torque. If bolt torque is not over 90 lb-ft. after tightening an additional 1/4 turn, bolt should be replaced.
3. Reverse remaining removal procedures to complete installation.