How to check the valve lash on a Fiat 124 Spider

Valve adjustment starts with determining the clearance the valves have now, with present shim thickness, and calculating new shim thickness to bring lash into specification. On the intake valves, the lash should be .45mm. If the present lash is .70mm, and the shim is 3.65mm, you will need a new shim that is 3.90mm to take up the difference. It is not a quick procedure.

Camshaft covers are removed with 12mm Allen HEX wrench.
Cam galley still has oil soaking the camshaft.
Use a gravy baster to remove as much as possible.
Directly under the cam lobe is the shim in the top of the tappet bucket.
With the cam pointed up, slide the feeler gauge blade between the shim and back of lobe. Start with a thin blade and use progressively thicker ones until it won't fit. Then go one size smaller. This is your valve clearance or "lash".
Use needle nose pliers to extract shim from its bucket tappet.
Special camshaft tool holds tappet away from cam lobe.
Digital caliper or micrometer gives shim thickness. Simple arithmetic determines replacement shim thickness needed for correct valve clearance.

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