350 Chevy Camshaft Installationby Moss Strohem
Changing the camshaft on a small block Chevrolet 350 engine is a project that requires methodical disassembly, inspection and reassembly of many parts on the engine. Since the camshaft and lifters are internal components, several external parts will need to be removed first in order to complete this task. Additionally, careful attention must be given, when re-installing the replacement parts, in order for the engine to run properly upon completion of the swap. A clean, organized workspace is helpful in this regard.
Secure the car wheels with blocks or set the parking brake so that it will not move while working on/under it. Drain the oil and engine coolant. Remove the cooling fan shroud from the radiator. Note that on some vehicles with little clearance between the radiator and the front of the engine block, the radiator will also need to be removed. Allow for at least 24 inches of room so that the camshaft can be slid forward out of the engine block. Remove all belts and accessories attached to the front of the engine so that the timing cover can be removed. This may include brackets for the power steering, electrical and A/C systems. Remove the water pump. After removing the harmonic balancer bolt, use a harmonic balancer puller to slide the balancer off of the crankshaft snout.
Disconnect all hoses and vacuum/electrical wires so that the distributor and intake manifold/carburetor can be removed. Remove the distributor bolt and lift the distributor up and out of the engine. Remove the intake manifold bolts and lift the intake manifold/carb off the engine. Remove the valve cover bolts and covers. Loosen all rocker arm stud bolts and remove the push rods (there are eight per side on the 350 V-8 engine). Remove the timing cover bolts. Remove several of the most forward oil pan bolts and loosen the remaining bolts so that the front of the oil pan can be lowered to allow the timing cover to be removed.
Remove the camshaft sprocket bolts then remove the sprocket so that the timing chain can be removed. Reattach the camshaft sprocket. Remove the camshaft lifters from the engine (top-side, from the lifter valley). Carefully slide the camshaft forward and out of the engine block. Be certain to balance and support the weight of the cam completely until it is safely out of the engine to avoid scraping/damaging the camshaft journal bearings.
Install the camshaft sprocket on the new cam and lubricate the replacement cam. Follow the manufacturer's installation lube procedures for cam lobes and lifters to avoid camshaft damage upon re-starting the engine. Carefully slide the camshaft into the engine until it is fully inserted. Remove the cam sprocket so that the timing chain can be installed, making sure that the timing marks on both the cam and crank sprockets align at their nearest point. Tighten the cam sprocket bolts to the proper torque value. Insert the lifters into the lifter bores. Reinstall the push rods and pre-load the valve lash according to the cam manufacturer's instructions.
Reinstall the timing cover with new gaskets and reattach the oil pan to the lower portion of the timing cover. Replace all the external components on the front and top-end of the engine in the reverse order they were removed. Replace all engine fluids to their proper levels. Upon re-start, some camshafts (flat tappet designs) require the engine to be operated for 20 to 30 minutes at 2,000 RPM or more to break in the camshaft. Re-start the engine following the cam manufacturer's instructions.
Things You'll Need
- Replacement cam and lifters
- Top-end and timing set gasket kits
- Tools (including balancer and crankshaft timing gear puller)
- Engine fluid drain pans
- Replacement engine oil and coolant
Moss Strohem has a background in business and finance, and an avid interest in youth sports, health, nutrition and physiology. He writes both technical information and market commentary as a private consultant and has researched and authored business plans.