Valve Dimensions

	924 turbo
Intake valve	Exhaust valve	Intake valve	Exhaust valve
a) Æ40mm	Æ 33mm	Æ 40mm	Æ 36 mm
b) Æ8.97 mm	Æ 8.95 mm	Æ 8.97 mm	Æ 8.95 mm
c) 137.2mm	136.95 mm	133.2 mm	133.35 mm
d) 2.2...3.0 mm	2.2...3.0 mm	2.2...3.0 mm	2.2...3.0 mm
a 45°	45°	45°	45°

Checking Valve Guides

Insert new valve into guide until valve stem end is flush with end of guide. Ascertain play.

Wear limit for intake valve guide 0.8 mm

Wear limit for exhaust valve guide 1.0 mm

Adjusting Screw Notching

The number of notches indicates the thickness of the valve adjusting screws.

Higher number of notches = thicker adjusting screw

New adjusting screw Part no.	Identi­fication
046.109.453.D 046.109.453.E 046.109.453 F 046.109.453 G 046.109.453 С	1 notch 2 notches 3 notches 4 notches without notch	The replacement adjusting screw will continue to be available, but without any marking (previously white dot of paint).

Checking and Adjusting Valve Play Reworking Intake Valves

Valve play is checked and adjusted with the engine at operating temperature (oil temp. approx. 80°C.)
Intake valve: 0.20 mm Exhaust valve: 0.45 mm
Basic valve play setting (for engine overhaul etc.)
With engine cold Intake valve: 0.10mm Exhaust valve: 0.40 mm	When reworking the valve, dimension a = 3.5 mm must not be exceeded. Note Exhaust valves must not be reworked. Only grinding to size is permitted.

Reworking Valve Seats

Valve seats with traces of wear or burning may be reworked until the wear limit "b" is reached. If the wear limit is exceeded, the cylinder head should be replaced, as the prescribed valve play can no longer be set, and valve seat rings cannot be replaced using conventional workshop equipment.

Дата добавления: 2015-11-16