Engine Running

Note: Static checks (engine off) are to be made on the engine prior to the dynamic analysis.

Note: Prior to performing any dynamic checks, ensure the transaxle is in PARK (A/T) or NEUTRAL (M/T) and the parking brake is fully engaged.

Start and idle the engine. Check for proper operation of all parts.
^ Check for plugged oil feed holes in the cylinder head.
^ Check for proper valve train lubrication. If insufficient oiling is suspected, accelerate the engine to 1200 rpm ± 100 rpm with the engine at normal operating temperature. Oil should spurt from the oil feed holes such that valve tips are well oiled and/or, with the valve cover off, oil splash may overshoot cylinder head. If oiling is insufficient for this to occur, check oil passages for blockage.

Camshaft Lobe Lift
Inspect the camshaft lobe lift. Replace the camshaft if the lobe lift is not within specification.

Camshaft Lobe Lift - Valve Tappet
Valve tappet noise may be caused by any of the following:
^ excessive valve tappet gap.
^ sticking valve tappet plunger (SPI engine).
^ sticking valve tappet bucket (Zetec engine).
^ worn valve tappet shim (Zetec engine).
^ valve tappet check valve not functioning properly (SPI engine)
^ air in lubrication system.

A sticking valve tappet plunger may be caused by dirt, chips or varnish inside the valve tappet.

Excessive valve tappet gap may be caused by excessive wear on valve tappet face or shim. Check gap between valve shim and camshaft to determine if any other valve tappet parts are damaged, worn or out of adjustment.

A valve tappet check valve that is not functioning may be caused by an obstruction such as dirt or chips that prevent it from closing when the camshaft lobe is lifting the valve tappet. It may also be caused by a broken check valve spring.

Air bubbles in the lubrication system will prevent the valve tappet from supporting the valve spring load. This may be caused by incorrect oil level or by air being drawn into the system through a hole, crack or leaking gasket on the oil pump screen cover and tube.

Rocker Arm
^ Check for plugged oil in the rocker arms or cylinder head.
^ Check for proper overhead valve train lubrication.
If insufficient oiling is suspected, accelerate the engine to 1200 rpm ± 100 rpm with the transmission in NEUTRAL and the engine at normal operating temperature. Oil should spurt from the rocker arm oil hole such that valve tips and rocker arms are well oiled and/or, with the valve covers off, oil splash may overshoot the rocker arms. If oiling is insufficient for this to occur, check the oil passages for blockage.