Camshaft Lobe Lift

ENGINE COMPONENT TEST

Camshaft Lobe Lift

Inspect the camshaft lobe lift. Replace the camshaft if the lobe lift is not within specification. See appropriate Mazda B-Series Engine Service Information.

Camshaft Lobe Lift - Valve Tappet, 2.3L, and 4.0L Engines

Valve tappet noise may be caused by any of the following:

- Excessive valve tappet gap
- Sticking valve tappet bucket
- Air in lubrication system
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. Valve clearances are adjustable on the 2.3L engine. See - Adjustments.
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.