Because bowling was completed, I perform the lapping of the valve.
I removed the valve and observed the valve face and valve seat.It is receiving damage.

This is a valve seat.

This is the valve face.

I attach a valve compound and do lapping.
The sucker is called a valve octopus.

There are 16, too.

I completed the work in a few hours.

The brim of the sleeve protrudes from the upper surface of the cylinder block.
(I designed it like that.)

So I reduce the top surface of the cylinder together.This work is called surface polishing.
It is a unique name for sharpening the joint between the cylinder head and the cylinder.
Originally, polishing is to grind with a grindstone.And cutting is to sharpen it with a knife.
But, as in this time cutting is also called face grinding.

It turns around with a Pick test,pick up the center coordinates.

As a result, I found that the bore pitch was 61 mm – 90 mm – 61 mm.

I will prepare the boring head.
The chip uses a thing for castings.

With this scale it is possible to adjust the protrusion amount of the blade with 1/1000 units.

And, I prepare a cylinder bore gauge for measurement, too.

And I do boring.My aim is φ 49.00 mm.
I make φ 48.995mm with boring.Then I make 49.000 by honing.

The animation of a series of processes is this.