Newbie Question--What's a top end rebuild?

[mkimber]

I keep on seeing references to a "top end rebuild." How is a top end rebuild different from a complete engine rebuild? How will I know (shudder) when I should do one (or have it done)?

[wholberg]

The "top end" is usually everything "above" the engine block, although this is normally more accurate for american engines.

On a Porsche a top end rebuild is, at a minimum, a valve job. Depending upon what it found when the engine is taken apart, it may also include new piston rings, or even new pistons and cylinders.

The common symptom of needing this work is excessive oil consumption. More severe symptoms can include excessive blow-by past the rings or valves.

[mkimber]

Thank you for the great answer!