Hello friends, welcome to all of you in a new post, in this post we will know what is a hydraulic valve lifter in an engine. And what is the use of this in the engine? So let’s know without delay. About the hydraulic tappet
What is a hydraulic tappet?
As you all know. The engine is the main part of a vehicle. And it is made up of many parts. He is one of them. hydraulic tappet is used more in the present time.
In earlier times mechanical valve lifters were used instead. But with changing technology, hydraulic tappet is used at present.
There is less noise in this. Because tappet clearance is not kept in it. A reservoir and a cylinder are used in this. It has a body hole connected to the oil pressure line.
Through which the oil comes from the lubrication system to the reservoir. Along with this, a plunger is used in the cylinder. Whose upper end is mated to a push rod valve stem?
The lower end remains attached to the oil. When the engine valve is closed, the oil ball in the reservoir opens. Due to this, the plunger rises up.
This eliminates the gap between the lifter assembly and the push rod valve stem. When it comes to the top, it is like this. So with that, the lifter rises up.
And the wall check is closed. And the oil doesn’t go into the reservoir. This causes the lifter assembly to rise up and open the valve. At the same time some oil leaks between the plunger and the cylinder. Due to this, the plunger comes down. And the valve closes.
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What is a valve seat?
The faces of the engine valves sit on these valve seats by sticking the valves. Due to which gases do not leak. It remains at such a place in the cylinder block or cylinder head.
Where the combustion chamber can push them, in other words, it can be said. That this valve seat is made at such a place. where the combustion chamber can open
What is valve clearance.?
The valves are usually fitted on the upper side of the engine. And when the engine is running. So due to the heat of the engine, these valves also get heated. And due to heat, their volume increases.
Because of this, the valves are not able to close and open properly. And it does not affect the engine due to the valves not opening and closing on time.
Also, delayed valve closing and delayed opening if the valves open from the middle of the push rod. So there is a danger of the push rod being crooked.
Engines in which the valves are fitted in the engine head. They are fitted with a clearance screw with a rocker. And the gap between the rocker and the valve stem is set by means of a screw.
and engines in which the valve is mounted in the engine block. In them, the adjustment screw is fixed on the top of the tappets. And through this, the gap between the tappet and the valve stem is adjusted.
These valve clearances are determined by the manufacturer based on the metals used in the valves. This clearance mostly ranges from 0.5 to 0.15.
How to repair the engine valve?
when the engine starts. So the valves also do their work with the engine. Due to the long run, the faces of the valves get worn. There are other reasons for this.
That is the tappet clearance, due to its extra soil etc., there is also a reason for their deterioration. And also due to the extra-rich mixture, carbon gets deposited on the valves.
Due to this, the compression starts leaking. And this affects the engine. To avoid this type of problem, worn and damaged valves can be re-grinded with a valve-facing grinding machine.
It is necessary to take care of one thing in this. That is the angle at which the valve seat remains. The valve should be ground at the same angle.
And one more thing should be kept in mind the valve should not be ground too deeply. The reason for this is this. That the upper surface of the valve is hardened to some depth only.
In this case, if the valve is ground, the margin of the valve becomes less than 1×6. So it cannot be used. Also, there is a lot of gas pressure on the valves. And there is also a risk of gas leaking due to the thin margin.
Following are some of the reasons for the early wear of valves –
The timing of the valves is damaged.
Damaged valve guides are stuck in the valve stem.
The valve stem is bent.
Valves are not properly seated.
The valve spring is weak.
In this post, you learned what is a valve tappet lifter. And what does it do? And also know what is a valve tappet. Hope you liked this post, how did you like this post, send us your suggestions in the comment box. And also share this post with others and follow us on FACEBOOK and INSTAGRAM