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Flattening a cylinder head.

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I want to know if my cylinder head is flat or not and wanted to flatten it if not.

How do you go about this??

Sand paper taped to a flat surface is WRONG.

The paper bunches up and forms a wave in front of your head so do NOT use sand paper taped down.

I know everyone has done it but it isn't the best method.

I am fortunate in having a surface plate. It is guaranteed to .0005 over the entire surface.

Clean the stone so there are no particles on it and then use it dry. Just take the head after AFTER it is clean, nothing on the sealing surface and run it around the DRY stone.

High spots will appear shiny. Lightly sand the shine off in those spots and do it again, and agian , and again.

Suprisingly after a few sands the area will spread out, the number becomes more.

Keep dry polishing on the bare stone and before long the entire head, or most of it anyway is shiny.

Hand sand the shiny spots and repeat until done.

It works. Took me about 15 minutes and most of my head sealing surface is being touched .

The stone doesn't bunch up in front of the head. The head is easy to remain flat on the stoen and the hand sanding just takes a little at a time.

Good luck

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I work in a Diesel fuel injection shop, and quite often we have to reface pump housings etc. we use two surface plates, the first has a sheet of 280 wet and dry paper on it, use oil to hold the paper to the plate. The other plate has a sheet of plate glass on it and we use oil based fine lapping compound to finish. The glass is replaced every two weeks.

Works very well on single cylinder heads etc. Must remember to always use a figure 8 pattern and rotate the head to keep the surface square .

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