How to replace a piston

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The old gasket is removed and the surface area cleaned so that a fresh and clean area is ready to accept the new gasket

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The freshly bored and honed cylinder are now ready for reassembly

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With everything inspected and replaced, it was time to put in a ring to test the end gap/ring gap.

There are a few ways to achieve this and Eric prefers to gently use the piston to push in the top ring into the cylinder

[Pappy]

A Feeler gauge is used to check the distance between the ends f the ring and if it is in spec, reassembly can continue. Your manual will have this detailed and usually the piston will include the specs for the particuliar application.

[Pappy]

The top ring will usually have a number or symbol stamped into it denoting the side that will be positioned towards the top of the piston.

[Pappy]

Just to show how the rings should look when installed, they should go end to end with the proper amount of freeplay or gap between the ends

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This would be the wrong way as this picture of the expander ring shows them overlaping ends

[Pappy]

Once the rings are installed in their proper position and the gaps either adjusted or at the correct measurements, you will want to make sure that the rings do NOT line up with each other. Having all the end gaps perfectly aligned would cause some issues as the engine would not seal the combustion chamber correctly and damage would occur.

[Pappy]

And not every piston will come stamped with a symbol to tell you which way it should face in the cylinder. On this piston, the valve reliefs show us how it should be installed to align with the intake and exhaust valves, others may have a symbol showing the proper direction of install. This can be complicated if you dont take your time and think things out especially when the engine is out of the frame and the head isnt positioned correctly when you make your determination on which way to install the piston. A carefull look at what your working with should steer you in the right direction and a double read of the manual.

[Pappy]

The new Wrist pin is coated in assembly lube and readied for installation