F 150 2WD Pickup V6-4.2L VIN 2 (1997)
Camshaft: Testing and Inspection
Lobe
Lobe Lift
Check the lift of each lobe in consecutive order and make a note of the readings.
1. Remove valve covers.
2. Remove rocker arm seat bolts, rocker arm seat and rocker arms.
3. Make sure valve tappet is seated against camshaft. Install (A) Dial Indicator With Bracketry so the ball socket adapter of the indicator is on top of
the valve tappet or (B) Cup Shaped Adapter is on top of push rod and in same plane as valve tappet push rod movement.
4. Remove sparkplugs.
5. Connect an auxiliary starter switch in the starting circuit. Crank engine with ignition switch in OFF position. Bump crankshaft over until valve
tappet is on base circle of camshaft lobe. At this point, valve tappet will be in its lowest position. If checking during engine assembly, turn
crankshaft using a socket or ratchet.
6. Zero the dial indicator. Continue to rotate crankshaft slowly until valve tappet is in fully-raised Position (highest indicator reading).
7. Compare total lift recorded on dial indicator with specifications.
NOTE: If lift on any lobe is below specified service limits, camshaft and valve tappet must be replaced.
8. To check the accuracy of the original dial indicator reading, continue to rotate the crankshaft until indicator reads zero.
9. Remove the dial indicator, adapter and auxiliary starter switch.
10. Install rocker arm seats, rocker arms and rocker arm seat bolts.
CAUTION: After installing rocker arms, do not rotate crankshaft until valve tappets have had sufficient time to bleed down. To do otherwise may
cause serious valve damage. Manually bleeding-down valve tappets will reduce waiting time.
11. Install valve covers.
12. Install spark plugs.
Lobe Surface
Inspect camshaft lobes for pitting or damage in the active area. Minor pitting is acceptable outside the active area.
