There are two basic types of cylinder heads used on today’s automobiles: the Overhead
Valve (OHV) and the Overhead Camshaft (OHC). The latter can also be broken down into
two subgroups: the Single Overhead Camshaft (SOHC) and the Dual Overhead Camshaft
(DOHC).
Most cylinder heads are made of an aluminum alloy because it is light weight, highly
durable and transfers heat well. However, cast iron was the material of choice in the past,
and is still used on many vehicles today. Whether made from aluminum or cast iron, all
cylinder heads have valves and seats. Some use two valves per cylinder, while the more
hi-tech engines will utilize a multi-valve configuration using three, four and even five valves
per cylinder. All cylinder heads have a valve guide for each valve. The guide centers the
valve to the seat and allows it to move up and down within it. The clearance between the
valve and guide can be critical. Too much clearance and the engine may consume oil, lose
vacuum and/or damage the seat. Too little, and the valve can stick in the guide causing
the engine to run poorly if at all, and possibly causing severe damage. When the valve
contacts the seat, sealing the combustion chamber, it does so with precision-machined
surfaces. The last component all cylinder heads have are valve springs. The spring holds
the valve against its seat. It also returns the valve to the closed position after the valve has
opened. The spring is held in place around its corresponding valve by a retainer and valve
locks. Aluminum heads will also have a valve spring cup to prevent the spring from
wearing away the aluminum of the cylinder head.
Содержание TrailBlazer
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Страница 26: ...Fig 3 Typical body and undervehicle maintenance locations Refer to chart for descriptions ...
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Страница 59: ...Cylinder head bolt removal and installation 32 Remove and discard the bolts from the cylinder head ...
Страница 175: ...Spring free length check Valve spring squareness check ...
Страница 192: ...Front of piston mark ...
Страница 361: ...5 3L Engine Except Saab Underhood Fuse Block 2003 2005 Early Production ...
Страница 469: ...Removing the outer band from the CV boot Removing the inner band from the CV boot ...
Страница 470: ...Removing the CV boot from the joint housing Clean the CV joint housing prior to removing boot ...
Страница 471: ...Removing the CV joint housing assembly Removing the CV joint ...
Страница 472: ...Inspecting the CV joint housing Removing the CV joint outer snap ring ...
Страница 473: ...Checking the CV joint snap ring for wear CV joint snap ring typical ...
Страница 474: ...Removing the CV joint assembly Removing the CV joint inner snap ring ...
Страница 475: ...Installing the CV joint assembly typical ...
Страница 506: ...Tie Rod End Removal Installation Inner Tie Rod End To Remove Inner tie rod assembly Magnasteer ...
Страница 553: ...9 Torque the lug nuts to specification 10 Lower the vehicle ...
Страница 556: ...Toe in Frame Misalignment Frame misalignment ...
Страница 588: ...Bleeding caliper ...
Страница 596: ...Inboard brake pad removal and installation 10 Remove the inboard brake pad from the brake caliper ...
Страница 624: ...Manifold gauge set components Refrigerant recovery recycling station ...
Страница 662: ...Lower instrument panel retaining volts 25 Remove the lower retaining bolts from the instrument panel I P ...
Страница 676: ...A C Specifications ...
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