Valve springs

Make

Alfa Romeo

Model

145/146 Factory Service Manual

Year

1994–1999

Section

Engine › Valve springs

Technical data and maintenanceValve springs

Valve springs

Free length "L1"	Inner spring	Outer spring
Length with valves closed "L2"	32.25 mm	30.25 mm
Corresponding load at "L2"	23 ÷ 24.4 kg	11.6 ÷ 12.5 kg
Length with valves open at "L3"	23.25 mm	21.25 mm
Load corresponding to length with valves open	43.3 ÷ 46.1 kg	20.4 ÷ 21.8 kg

Camshaft bearings

	Front "a"	35.015 ÷ 35.040
Diameter of camshaft bearings	Centre "b"	48.000 ÷ 48.025
	Rear "c"	49.200 ÷ 49.225
Diameter of valve cup seats "d"	35.000 ÷ 35.025

Camshafts

	Diameter of camshaft journals	Front "a"	34.940 ÷ 34.961
	Centre "b"	47.940 ÷ 47.956
	Rear "c"	49.140 ÷ 49.156
Maximum cam lift	Intake	9.80 (*)
	Exhaust	9.00
Clearance between camshaft journals and their housings	Front	0.054 ÷ 0.100
	Centre - rear	0.044 ÷ 0.085
(*) 9.00 for 1351 c.c. engine after change and 1596 c.c. Rochester.

Hydraulic tappets

	Unit: mm
Outside diameter of hydraulic tappet "a"	34.959 ÷ 34.975
Clearance between hydraulic tappets & their housings	0.025 ÷ 0.066

ANGLES OF ACTUAL TIMING DIAGRAM

	Intake	Opens (before T.D.C.)	(a)	30°
	Closes (after B.D.C.)	(b)	84° (Δ)
	Intake angle	(c)	294° (□)
Exhaust	Opens (before B.D.C.)	(d)	68°
	Closes (after T.D.C.)	(e)	34°
	Exhaust angle	(f)	282°
(Δ) 76° (□) 286°: for 1351 c.c. engines after change and 1596 c.c. Rochester

(1) Intake (2) Exhaust
(A) T.D.C. (B) B.D.C.

02 Maintenance