What is an integral valve guide?
A valve guide is a cylindrical piece of metal, pressed or integrally cast into the cylinder head, with the valve reciprocating inside it. Guides also serve to conduct heat from the combustion process out from the exhaust valve and into the cylinder head where it may be taken up by the cooling system.
What are the two types of valve guides?
Material choices for guides are down to two distinct types – cast iron and bronze.
How much clearance should valve guides have?
A general rule of thumb is that intake guides need guide-to-stem clearance of . 001″ to . 003″ and exhaust guides need from . 002″ to .
What does a valve guide do?
The Valve Guide supports the intake/exhaust valve stem, stabilizes the valve attitude and allows heat to escape to the cylinder head side, hence, it needs to be durable and made with great precision.
What are the three types of valve guide seals?
Either way, the engine is going to have problems.
- There are three types of valve guide seals: umbrella, positive, and O-ring [ see Figure 4 ].
- The umbrella seal, used on many older engines, fits snugly over the valve stem.
- The O-ring seal was used on many millions of older General Motors engines.
Do valves need new guides?
Valve guides are reusable until they are worn out; you don’t replace them unless they are worn beyond usefulness.
What is integral valve seat?
Seats of a Gate valve Integral seats provide a seat of the same material of construction as the valve body while the pressed-in or threaded-in seats permit variation. Rings with hard facings may be supplied for the application where they are required.
Can you reuse valve guides?
Valve guides are reusable until they are worn out; you don’t replace them unless they are worn beyond usefulness. When they wear out, you can usually do one of three things: knurl; valve guide sleeve; new valve guide.
What are 2 types of valve stem seals?
There are two basic valve stem seal designs: deflector (umbrella) seals and positive seals. Positive seals attach to the valve guide boss. They work like a squeegee, wiping and metering oil on the stem as it passes through the seal. Deflector seals, like the name implies, deflect oil away from the valve stem.