COILS for valve seats and other tools for grinding ICE valves

COBS for valve seats are a tool, with which the car engine (or rather, its valve mechanism) returns to working order after repairs. With the help of such cones, which are also called countersinks, the tightness of working cylinders of the engine is restored, which is one of the main conditions of its technically sound condition.

A complete set of tools for repairing valve seats

How the valve mechanism of a car engine works

To understand the peculiarities of the use of cones or countersinks for valve seats, it is necessary to understand that first, how the valve mechanism of the car engine works, as well as in that, which can lead to malfunctions in its operation.

Each of the cylinders of any internal combustion engine (ICE) works together with two valves, one of which is the intake, and the second - graduation. The work of the internal combustion engine is carried out due to repetitive processes (cycles). Each of these processes is, that the fuel mixture is fed into the working cylinder. This occurs when the intake valve is opened. After its closing and combustion of fuel mix from the cylinder it is necessary to deduce exhaust gases, which is provided by the opening of the exhaust valve. Intake and exhaust valves, being in the closed state, must ensure complete tightness of the working cylinder.

Scheme of the valve mechanism of the internal combustion engine

During engine operation, the valves are subjected to significant mechanical loads, and various influences of the aggressive environment, in which they are operated:

• thermal;
• mechanical;
• dynamic;
• chemical.

That the valves were able to withstand such serious influences for a long time, high-alloy steel alloy is used for their production, in the chemical composition of which contains a significant amount of chromium and nickel.

During operation, the valve seats wear to varying degrees

The design of valves consists of two main elements: guide rod and head, which may be flat, convex or tulip-shaped. The guide rod of the valve can be completely cylindrical or made with a shaped groove, which is necessary for more reliable fixing of a spring.

They, that there are malfunctions in the valve mechanism of the internal combustion engine, can be determined by several features, the most obvious of which are:

• reduction of engine power, which affects the speed characteristics of the car;
• unstable operation of the internal combustion engine at any speed;
• unnatural knock, emanating from the engine compartment of the car;
• a lot of smoke, coming out of the exhaust pipe.

The appearance of a gap between the valve and its seat leads to the formation of soot, and subsequently to the burnout of the valve seat

If we talk about the most common faults of the internal combustion engine, associated with its valve mechanism, then they belong:

• the appearance of a gap between the cylinder block and the head, which is equipped with such a unit, due to their loose fit (this gap, formed for a number of reasons, leads to depressurization of the system);
• education in places, where the valve is in contact with the cylinder block, coke and soot (such soot does not allow the valve to completely close the cylinder, which also leads to depressurization of the system).

Tools for repair of the valve mechanism

The most common tool for repairing valve seats is a cone (countersink). It should be borne in mind, that such a countersink is not a countersink, by means of which carry out countersinking.