Workshop Manuals Factory service & repair Alfa Romeo
Alfa Romeo 145/146 Engines, 146 Bodywork and Engine Overhaul Manual (1994-2001)12 · Engine overhaul: 3.0 V6 (AR16101)
12 · Engine

Checking the valve springs

Make
Alfa Romeo
Model
145/146 Engines, 146 Bodywork and Engine Overhaul Manual
Year
1994–2001
Section
Overhauling › Checking the valve springs
Engine overhaul: 3.0 V6 (AR16101)Checking the valve springs
  • Calculate the clearance between valve guides and valve stems and check that it is within the specified limits; if not, change any worn parts.
Radial clearance between valve guides Intake Exhaust
and valve stems 0.040 + 0.090 mm 0.013 + 0.043 mm
  • Ream the inside diameter of the valve guides to calibrate the holes to the specified diameter.
  • Check that the "free" length of the valve springs is within the specified limits.

NOTA: The resting planes must be parallel with one another and perpendicular to the axis of the spring with a maximum error of 2°.

Checking the valve springs

Free length of valve springs Outer spring "La" Inner spring "Lb"
44.6 mm 44.1 mm
Illustration showing removal of worn valve guides using a puller tool (A.3.0134) with specified torque values.
1. Using puller tool no. 1.821.005.000 (A.3.0134), remove the worn valve guides.

Inserting new valve guides in their seats using the tools illustrated.

Illustration showing insertion of new valve guides into cylinder heads with specified torque values.
1. Insert the new valve guides in their seats using the tools illustrated.
  • Check that the outside diameters of the valve guides and their seats on the cylinder heads are within the specified limits and meet the assembly interference.
Outside diameter Diameter of valve guide seats Seals - valve guide interference
of valve guides 14.048 + 14.059 mm 0.030 + 0.069 mm
Diameter of valve guide seats 13.990 + 14.018 mm
  • Using a torque meter, check that the characteristic data of the springs are within the specified limits.
Illustration showing valve spring specifications for inner and outer springs with control load and spring length values.
Inner spring
Spring length Control load N (kg) With valve closed With valve open
mm 30.5 126 + 130 (12.8 + 13.3) 21.5 222 + 231 (22.7 + 23.5)
Illustration showing valve spring specifications for inner and outer springs with control load and spring length values.
Outer spring
Spring length Control load N (kg) With valve closed With valve open
mm 32.5 243 + 252 (24.8 + 25.7) 23.5 470 + 488 (47.9 + 49.7)
  • Check that the inside diameter of the valve guides is 9.000 + 9.015 mm.
Illustration showing inside diameter of valve guides with specified tolerance.
Inside diameter of valve guides

Parts & tools for this job For 1994 Alfa Romeo 145/146

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