Alfa Romeo Camshaft Timing and Installation
Included in this document is a cam-timing template. Follow the instructions for the template to check the timing marks on the front camshaft bearing caps. If necessary, scribe new timing marks onto the cam caps.
To install the camshafts, start by putting the engine to Top Dead Center (TDC) - #1 cylinder. TDC #1 is when the #1 cylinder piston is at the top of it’s stroke, and the #1 camshaft lobes are pointing to the outside of the engine (intake lobe pointing toward the intake manifold, exhaust lobe to the exhaust manifold). TDC is the “P” mark on the crankshaft pulley. Make sure the timing pointer on your engine is really pointing to TDC. It is best to use a TDC gauge to check this. Adjust the pointer if necessary. Remove the original camshafts following the instructions in your Alfa shop manual. Transfer the two camshaft sprockets to the new cams to be installed. Inspect the cam followers for wear. If there are any irregularities or crazing on the tappet surface (where the lobe hits), replace the tappets.
If the cylinder head is on the bench, install the cams and adjust the valves before installing the head onto your car. Be aware that when the cams are installed open valves will extend below the surface of the head. Do not lay the head down on its surface, as valves will be bent.
Lubricate the camshafts journals, lobes, and cam followers liberally. Do not turn the cams dry for any reason. If necessary, the cam journals can be cleaned up with some emery cloth and your thumb
.
If the head is on the car, after disconnecting the timing chain, turn the crankshaft counterclockwise 90 degrees to get plenty of valve-to-piston clearance. Now you can remove and replace the cams, as well as turn each cam independently for ease of valve adjustment, without hitting a piston with a valve. After the valves are adjusted, line the cams up with the timing marks on the cam caps. Turn the crankshaft clockwise to TDC. Following the instruction in your shop manual, adjust the camshaft timing and chain tension, tighten the cam nuts, and install the small bolts and lock nuts.
To install the camshafts, start by putting the engine to Top Dead Center (TDC) - #1 cylinder. TDC #1 is when the #1 cylinder piston is at the top of it’s stroke, and the #1 camshaft lobes are pointing to the outside of the engine (intake lobe pointing toward the intake manifold, exhaust lobe to the exhaust manifold). TDC is the “P” mark on the crankshaft pulley. Make sure the timing pointer on your engine is really pointing to TDC. It is best to use a TDC gauge to check this. Adjust the pointer if necessary. Remove the original camshafts following the instructions in your Alfa shop manual. Transfer the two camshaft sprockets to the new cams to be installed. Inspect the cam followers for wear. If there are any irregularities or crazing on the tappet surface (where the lobe hits), replace the tappets.
If the cylinder head is on the bench, install the cams and adjust the valves before installing the head onto your car. Be aware that when the cams are installed open valves will extend below the surface of the head. Do not lay the head down on its surface, as valves will be bent.
Lubricate the camshafts journals, lobes, and cam followers liberally. Do not turn the cams dry for any reason. If necessary, the cam journals can be cleaned up with some emery cloth and your thumb
.
If the head is on the car, after disconnecting the timing chain, turn the crankshaft counterclockwise 90 degrees to get plenty of valve-to-piston clearance. Now you can remove and replace the cams, as well as turn each cam independently for ease of valve adjustment, without hitting a piston with a valve. After the valves are adjusted, line the cams up with the timing marks on the cam caps. Turn the crankshaft clockwise to TDC. Following the instruction in your shop manual, adjust the camshaft timing and chain tension, tighten the cam nuts, and install the small bolts and lock nuts.
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