Chevrolet Cobalt Service & Repair Manual: Cylinder Head R&R
Removal
1. |
Remove air inlet duct and resonator. |
2. |
Disconnect IAC, TPS and MAP sensor. |
3. |
Disconnect EVAP and PCV hose. |
4. |
Disconnect purge solenoid tube and
brake booster hose. |
5. |
Remove oil dipstick tube bolt. |
6. |
Disconnect accelerator and cruise control
cables. |
7. |
Remove throttle body and fuel rail. |
8. |
Remove KS connector from intake manifold. |
9. |
Remove mounting nuts, bolts and intake
manifold. |
10. |
Remove power steering pump. |
11. |
Remove exhaust manifold heat shield. |
12. |
Remove oxygen sensor. |
13. |
Raise and support vehicle. |
14. |
Remove manifold to exhaust flex decoupler
mounting bolts. |
15. |
Pull down and back on exhaust pipe
in order to disconnect pipe from exhaust manifold. |
17. |
Remove exhaust manifold to cylinder
head mounting nuts. |
18. |
Remove exhaust manifold, clean sealing
surfaces. |
20. |
Drain coolant system into suitable
container. |
21. |
Remove cylinder head bolts in sequence,
Fig. 1. Discard bolts. |
22. |
Remove cylinder head and gasket. |
23. |
Reverse procedure to install, noting
the following: |
|
a. |
Install new cylinder head bolts. |
|
b. |
Using sequence, Fig. 2,
tighten cylinder bolts in two steps: First stop, torque cylinder
head bolts to 22 ft. lbs.; second step, tighten head bolts an additional
155°. |
|
c. |
Torque front cylinder head bolts
to 26 ft. lbs, Fig. 3. |
|
Fig. 1 Cylinder head bolt loosening
Fig. 2 Cylinder head bolt tightening sequence
Fig. 3 Front cylinder head bolt tightening
It is usually recommended to send
head to machine shop for complete overhaul.
Cylinder head must be cool before
removing it from engine. Cylinder head warpage can result if ...
Caution: Do not remove any
component of the engine emission control system. Operating the engine without
the engine emission control system intact will reduce fuel economy and engine
...
Chevrolet Cobalt Owners Manual
Chevrolet Cobalt Service Manual