CH06 - CHAPTER SIX Cylinder Heads Objectives You should be...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon
CHAPTER SIX Cylinder Heads
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Objectives You should be able to: Explain valve design and terminology. Explain the reasons for burned valves. Describe two types of valve seats. Explain the causes of valve seat recession. Explain the purposes of valve springs and seals.
Background image of page 2
Objectives (Cont’d) Describe the results of worn valve stem seals and guides. Describe eight different combustion chamber designs. Explain how the combustion process develops engine power. Explain how exhaust emissions can be reduced by combustion chamber design.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Objectives (Cont’d) Disassemble, clean, and inspect cylinder heads. Inspect cylinder head for cracks, and measure cylinder head warpage. Determine valve and valve spring condition. Inspect, measure, and service valve seats and valve guides. Determine the condition of rocker arms, pivots, shafts, and pushrods.
Background image of page 4
Cylinder Heads On most engines, the cylinder head contains the: valves valve seats, guides, and springs the upper portion of the combustion chamber passages to allow coolant and oil to flow through the head Is made of cast iron or aluminum
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Valves Valve terms Stem : guides the valve through its linear movement Head : the enlarged part of the valve Face : the tapered part of the valve head that makes contact with the valve seat
Background image of page 6
Valves (Cont’d) Valve terms (cont’d): Seat : the point at which the seal is made by the valve face Margin : the material between the valve face and the valve head Fillet : the curved area between the stem and the head
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Valves (Cont’d) Valve and seat purposes Allow air into the combustion chambers Expel exhaust from the combustion chambers Seal the combustion chamber Transfer heat from the valve to the cooling jacket in the cylinder head
Background image of page 8
Valves (Cont’d) Valve defects Burning Channeling Necking Breaking Sticking open Floating
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Valves (Cont’d) Valve seat types Integral Non-integral Valve seat defects Burning Pitting Recession
Background image of page 10
Valve Springs and Seals Valve spring purposes Closes the valve against the seat Prevents valve float Valve spring defects Broken Weak, improper height Bent or cocked
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Valve Springs and Seals (Cont’d) Valve stem seals Prevent oil from running down the valve stems into the combustion chambers May be O-ring, umbrella, or positive-type seals Worn seals may cause oil consumption and blue smoke in the exhaust
Background image of page 12
Valve Guides Maintains the valve position to provide proper valve face seating on the valve seat May be insert-type or integral Worn valve guides may cause improper valve seating, valve burning, compression loss, and valve breakage.
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Rocker Arms and Pushrods Pushrods Transfer valve lifter motion to the rocker arms Rocker arms A pivoting lever that transfers pushrod motion to the valve stem Rocker arm ratio gives rocker arms a mechanical advantage.
Background image of page 14
Image of page 15
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 58

CH06 - CHAPTER SIX Cylinder Heads Objectives You should be...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online