- What do valve guides do?
- Do worn valve guides make noise?
- What is Valve face angle?
- How are valve sizes measured?
- What is Valve interference angle?
- What are the methods used to repair a worn valve guide?
- What are the two types of valve guides?
- What is valve angle?
- What causes valve guide wear?
- How do you measure a valve seat width?
- How much should a valve job cost?
- How do I know if my valve guides are bad?
- How do you check a worn valve guide?
- What is Valve guide knurling?
- How do I choose valve length?
What do valve guides do?
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..
Do worn valve guides make noise?
So, If a valve spring has broken or a camshaft lobe is worn down; it will cause the engine to create a tapping or clicking sound; due to the excess clearance. Valve train noise is similar to a clicking sound of a sewing machine.
What is Valve face angle?
The face of the valve is usually ground to an angle of either 30° or 45°. In some engines, the intake-valve face is ground to an angle of 30°, and the exhaust-valve face is ground to a 45° angle. Valve faces are often made more durable by the application of a material called stellite.
How are valve sizes measured?
Always measure the inside diameter of the inlet/outlet port. This will identify the size of valve in question. A common mistake is that people measure the outside diameter of the inlet/outlet ports of a valve. There is one exception to this rule – if working with tubing – measure the outside diameter of the tubing.
What is Valve interference angle?
An interference angle is provided by an engine manufacturer to allow for quick bedding in off the valve face to the seat on new engines, and is not always used when reconditioning valve and seats.
What are the methods used to repair a worn valve guide?
The method of repairing worn valve stem guide holes in the head of an internal combustion engine through the use of a reamer having an elongated lead shank adapted to extend at least the major portion of the length of the valve guide holes, and a knurling tool having a thread base diameter substantially equal to the …
What are the two types of valve guides?
Valve guides – Materials and usage. Material choices for guides are down to two distinct types – cast iron and bronze.
What is valve angle?
Valve angle defined as the angle between a valve axis and a cylinder axis is one of the most important design factors that may have an influence on valve train design, cylinder head size, in-cylinder flow, etc.
What causes valve guide wear?
The valve guides experience a lot of wear; because of the constant friction between the guide and valve stem. … Side forces on the valve stem caused by changes in valve train geometry; or by direct acting overhead cams further contribute to guide wear.
How do you measure a valve seat width?
Measure the seat width with vernier calipers. It should measure approximately 1.1 mm (0.0433 in). Also, the seat should be uniform in contact area. If valve seat width varies, or if pits still exist, further cutting will be necessary.
How much should a valve job cost?
On newer engines (V6 or V8), a valve job can cost up to $125 per valve that needs repairing, with the cost increasing for engines with over 12 valves. Therefore, a total valve job can cost upward of $1000.
How do I know if my valve guides are bad?
In stop and go driving, you may notice that your car stays idle after you stop at stop lights or stop signs. If your car remains idle for extended periods of time, it means you have a bad valve guide seal. You will likely also notice large clouds of smoke coming out of your tailpipe each time you stop.
How do you check a worn valve guide?
Observe your car when you accelerate and brake. If you see a billow of smoke from the exhaust pipe — especially any blue smoke, which is caused by burning oil — it is a sign that the valve guides are worn.
What is Valve guide knurling?
Valve guides are knurled [internal] in the head. A knurling tool is inserted into the guide bore and as it is rotated and advanced the tool displaces steel making the bore smaller. Then the bores a reamed [slightly oversize] to match the diameter of the valve stems.
How do I choose valve length?
In most cases, adding 15mm to the height of the rim is a reasonable rule of thumb when it comes to deciding on a valve length. That extra 15mm is important because it provides enough length to fit any pump head.