Volkswagen Workshop Service and Repair Manuals > Polo Mk4 > Engine | 4 - Cyl. injection engine | Engine cylinder head, valve gear | Camshaft mechanism - repair | Valve seat - trim

Calculating maximum trim

–	Install valve and firmly press it against the valve seat.

Note

If the valve is replaced upon repair, use the new valve for measurement.

–	Measure the distance -a- between the valve stem final end and the upper edge of the cylinder head.

–	Calculate maximum and minimum grinding measurements of the measured distance.

Minimum measurements: Inlet valve and exhaust valve 32.1 mm.

Measured distance minus minimum distance = Maximum grinding measurement allowed.

For example:

-	Measured distance Minimum specification:	32,5 32,1	mm mm
=	Maximum grinding specification allowed*	0,4	mm

¹⁾	The max. grinding measurement allowed is shown in the illustrations to grind the valve seats as per measurement „b“.

Volkswagen Workshop Service and Repair Manuals