CYLINDER HEAD

ENG

CHECKING THE CYLINDER HEAD 1.Eliminate:

Carbon deposits (from the combustion chambers)

Use a rounded scraper.

NOTE:

Do not use a sharp instrument to avoid damaging or scratching:

Spark plug threads

Valve seats

2.Check:

Cylinder head Scratches/damage Replace.

Cylinder head water jacket Mineral deposits/rust Eliminate.

3.Measure:

Cylinder head warpage

Out of specification Resurface.

Cylinder head warpage:

Less than 0.03 mm (0.012 in)

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Measurement and resurfacing steps:

Place a straightedge and a feeler gauge across the cylinder head.

Use a feeler gauge to measure the warpage.

If the warpage is out of specification, resurface the cylinder head.

Place a 400 ~ 600 grit wet sandpaper on the surface plate, and resurface the head using a figure-eight sanding pattern.

NOTE:

To ensure an even surface rotate the cylinder head several times.

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Yamaha 5TE-F8197-10, LIT-11616-16-02 service manual Eng