SAAB WIS ONLINE

Camshaft Cleaning and Inspection

Camshaft Cleaning and Inspection


Special Tools

EN-49474 Magnetic Base Dial Indicator

For equivalent regional tools, refer to Special Tools .

Cleaning Procedure


1. Clean the camshaft in solvent.

2.
Warning

Wear safety glasses when using compressed air, as flying dirt particles may cause eye injury.


Dry the camshaft with compressed air.


Visual Inspection


1. Inspect the camshaft oil feed holes (1) to the camshaft position actuator for dirt, debris or blockage.


2. Inspect the threaded hole (2) for damage.

3. Inspect the camshaft position actuator locating notch (3) for damage or wear.

4. Inspect the camshaft sealing grooves (4) for damage.

5. Inspect the camshaft thrust surface (5) for damage.

6. Inspect the camshaft lobes (6) and journals (7) for the following conditions:

Excessive scoring or pitting

Discoloration from overheating

Deformation from excessive wear, especially the camshaft lobes

7. If any of the above conditions exist on the camshaft, replace the camshaft.


Camshaft Measurement


1. With the camshaft in a suitable fixture, measure the camshaft for wear.


2. Measure the camshaft journals for diameter and out-of-round using an outside micrometer. Refer to Engine Mechanical Specifications .


If the diameter is smaller than specifications, replace the camshaft.

If the out-of-round exceeds specifications, replace the camshaft.

3. Measure the camshaft runout using the EN 49474 indicator. Refer to Engine Mechanical Specifications .


4. Measure the camshaft thrust width for wear using a depth micrometer. Refer to Engine Mechanical Specifications .


5. Measure the camshaft thrust wall surface for runout using EN 49474 indicator. Refer to Engine Mechanical Specifications .


6. If the camshaft is damaged or worn beyond specifications, replace the camshaft. No machining of the camshaft is allowed.

7. Measure the camshaft lobes for wear using the EN 49474 indicator.


8. Place the EN 49474 indicator with the indicator tip on the base circle (1) of the camshaft lobe.


8.1. Place the EN 49474 indicator at zero .

8.2. Rotate the camshaft until the indicator tip is at the highest point (3) on the lobe. This reading is the lift of the camshaft lobe. Refer to Engine Mechanical Specifications .

8.3. If the indicated measurement is significantly lower than these specifications, replace the camshaft or engine performance will be reduced.