How to Install a Camshaft for Vehiclesby Contributing Writer
Many car enthusiasts consider the camshaft the "brain" of the engine. The camshaft's lobes orchestrate the opening and closing of the valves, which determines the engine's effective rpm range and power band. Replacing the the camshaft on a Chevy Vehicles engine is a fairly straightforward job, though it will take time, patience, and an understanding of auto mechanics. The specifics vary depending on the model year and design of your engine, but the basics still apply to all of the Vehicles engines.
Under The Hood:
- How to Install a Camshaft for a Chevrolet 350
- How to Install a Camshaft on a DOHC
- How to Install a Camshaft in Your Hot Rod
Remove the radiator fan shroud. Drain the radiator, unbolt it and remove it. Unbolt the cooling fan from the water pump and pry it off of the pump with a flathead screwdriver. Loosen the alternator and remove the belts. Remove the water pump bolts and pull the water pump off of the engine.
Disconnect the fuel lines, linkages and vacuum lines from the carburetor and intake manifold. Remove the manifold-to-head bolts and pull the manifold off of the heads. Remove the valve cover bolts and pull the valve covers off.
Clear off a clean spot on a large work surface. Unbolt the rocker arms from the heads one at a time. Be sure to keep the rocker arms in order and the nuts with their matching arms. Pull the push rods out as you go and keep them with their matching arms.
Spray all around the lifters with penetrating oil. Grasp each lifter with a pair of channel-lock pliers and pull up while rotating it back and forth and spraying it with oil. Remove all of the lifters and discard them.
Remove the oil pan bolts and drop the oil pan onto the cross-member. Remove the old oil pan gasket and clean the mating surfaces of the block and oil pan with a rag soaked in carburetor cleaner. Remove the bolts from the timing chain covers and pry the cover off of the engine. Unbolt the retaining bolts from the upper timing gear. Grasp the upper cam gear and pull forward. Work the gear and chain off of the crankshaft gear and remove it.
Install a bolt into the threaded hole on the front of the camshaft. Use the bolt as a handle to carefully wiggle the cam out of the block. Take your time to avoid damaging the cam bearings in the block.
Drop your new lifters into a container full of oil to prime them. Rotate the crankshaft so that the dot on the lower timing gear sits at the 12 o'clock position. If you're installing a new timing chain set (as you should), then pull the lower gear off of the crankshaft now. Coat the new camshaft's lobes with chrome-moly break-in lubricant to ensure the lifters break in properly. Coat the cam bearings and gear with assembly lube.
Slide the camshaft into the block. Proceed very carefully and slowly to avoid nicking the bearings. Give the cam a test-spin once you have it in. Wipe the oil off of the flat lower surface of your lifters and drop the lifters one-by-one into the lifter bores.
Install the new timing gears onto the cam and crankshaft, then rotate the cam until the dots on the cam and crankshaft gears line up. Pull the gears back off, slide the chain over them, and push the two gears and the chain onto the engine as a unit. Double-check that the dots are still lined up and re-install the cam gear retainer bolts.
Reassemble the engine in the reverse order of disassembly, using all new gaskets and seals where appropriate. Some engines require that you use sealant around the bolts. Torque values vary by model year and engine.
Turn the engine over either with the starter or by hand until you see the intake lifter on the number one cylinder (front-driver side) begin to rise. Once the intake lifter reaches full lift, tighten the exhaust rocker's nut until the exhaust lifter's plunger just begins to depress. Tighten the nut another half-turn and lock it in place with the jam nut. Repeat this process with the intake rocker, and repeat it 14 more times on all the other rocker arms. Reinstall the valve covers with new gaskets.
Reconnect all of the fuel lines, vacuum lines, electrical connections and linkages. Attempt to start the engine. Don't be alarmed if it doesn't fire up right away. You'll probably need to loosen the distributor bolt and rotate the distributor to adjust the timing. Follow your cam manufacturer's directions to set the timing and break in your new camshaft.
Items you will need
Basic hand tools
Chrome-moly break-in lubricant
Small paint brushes
Lint-free shop rags
Disconnect the battery by removing the negative cable with a socket and ratchet . Open the valve on the bottom of the radiator using a wrench. Drain the engine coolant into the drain pan. Relieve the pressure from the fuel system by opening the valve on the fuel rail. Remove the accessory drive belts from the engine. Disconnect the exhaust pipe from the manifold using a wrench.
Remove the power steering pump and bracket using a socket and ratchet to loosen the bolts. Remove the cylinder head cover using a socket and ratchet to loosen the bolts. Remove the distributor cap by loosening the screws with a screwdriver. Mark the rotor position in relation to the distributor and remove it.
Remove the distributor from the engine by loosening the bolts with a wrench. Remove the timing chain tensioner using a socket and ratchet. Remove the sprocket from the camshaft. Be sure to note the position of the camshaft because you will have to put the new one(s) in the exact same way.
Remove the camshaft bearings center caps, and work your way out using a socket and ratchet. Note the position of each bearing cap. You must install them the same way they came off. Remove the camshaft(s) from the engine. Put the new shaft(s) in and coat it with engine oil. Replace the bearing caps the same way they came off.
Install the bearing cap bolts and torque them to the following specs, making sure the camshaft(s) is/are in the proper positions as when they came off.
First pass bolts 11-15 to 18 inch-pounds and then bolts 1-10 to 18 inch-pounds
Second pass bolts 1-15 to 53 inch-pounds
Third pass bolts 1-14 to 87-105 inch-pounds
Last pass bolt 15 to 56-73 inch-pounds
Install the sprocket and timing chain. Install the bolt and tighten it with a socket and ratchet. Hold the other end of the camshaft with a wrench while you tighten the bolt. Install the timing chain tensioner and tighten the bolts with a socket and ratchet. Install the distributor according to the alignment marks and tighten the bolts with a wrench.
Install the rotor button according to the alignment mark. Install the distributor cap and tighten the securing screws with a screwdriver. Install the cylinder head cover and tighten the bolts with a socket and ratchet. Install the power steering pump and bracket using a socket and ratchet to tighten the bolts.
Connect the exhaust pipe to the manifold and tighten the bolts with a wrench. Install the accessory drive belts and route them according to the diagram under the engine hood. Connect the negative battery cable and tighten the nut with a wrench. Refill the radiator and reservoir with coolant.
Items you will need
Have some type of cart or table nearby where you can lay everything out as you take it off. Open the pack of lifters and soak them in some regular motor oil. Make sure all the lifters are covered in oil.Drain the antifreeze into a clean bucket. If you use a clean bucket, you can re-use the antifreeze. Drain the oil into a container proper for disposal. You will need to dispose of the oil and filter at a proper disposal facility.Also, before you start, you will need to make sure your engine is at top dead center.
Remove the radiator, radiator hoses, any electric fans, if you have them installed and the front grill. If you have a transmission cooler, remove that at this time, taking car to place a drip pan under the cooler lines. If you do not have a separate trans cooler, be sure to have a drip pan under the cooler lines that run into the radiator.
Remove the manual fan, and the alternator. Unbolt the mounting bolts for the power steering pump and lay it to the side. If you do not have enough room to lay it out of the way, you may have to take the hoses off. If so, be sure to have a catch bucket to catch any power steering fluid that will leak.
Unbolt the air compressor and lay that out of the way. If your air compressor is below the heads, it should not be in your way, and you do not have to unbolt it. Try to leave the lines intact, as you will have to vacuum the system down and replace the freon and the dryer or accumulator if you take the lines off.
Remove the valve covers. Take the old gasket off and clean the gasket rail. Inspect them carefully to be sure there are no dents or that the gasket rail is not warped. This is particularly important if you have chrome valve covers.
Remove the water pump. Clean any stuck on gasket with the carb cleaner.
Unhook the carb linkage from the side of the carb, the fuel lines and vacuum lines. You may want to lay some rags on top of the intake to catch any fuel that leaks out when you remove the fuel lines.
Remove the distributor. Take note of where the rotor is pointing. It should be pointing at the Number One cylinder if you properly set your engine at top dead center.
Remove the intake manifold from the engine. Remove the gasket. Use carb cleaner to remove any bits of gasket that are sticking to the block or to the intake manifold.
Remove the rockers and pushrods. Throw the old lifters away.
Remove the timing cover. Be sure the timing marks on the crankshaft are lined up. The timing mark on the crank should be straight up and the timing marks on the camshaft gear (top timing gear) should be straight down.Look for a cam button or a cam lock. These will have to be removed.
Remove the harmonic balancer. Remove the timing chain. The top timing gear will have to be eventually removed, but you can leave it attached to the camshaft for now, using it to gently pull the camshaft out of the engine.Gently remove the camshaft from the front of the engine.
Coat the new camshaft with oil treatment or the cam lube that came with the cam. Install the cam as to the specs for your application. (You can install cams "straight up" or x degrees before or after top dead center). Do not forget about the cam button or the cam lock.Put the new lifters in the lifter bores. Reinstall all parts as you removed them and re-fill and top off all fluids.
Follow the instructions on breaking in the camshaft. Most cars require 2,000rpm for 20 minutes.
Items you will need
Water pump gasket
Valve cover gaskets
Timing cover gasket
Intake manifold gasket
Pry bar (a/k/a Big Bertha)
Harmonic Balancer Puller
Rail of 1/4 inch standard sockets
Rail of 3/8 inch standard sockets
Rail of 1/2 inch standard sockets
Water pump pliers
1/4 inch ratchet
1/4 inch air ratchet
3/8 inch ratchet
3/8 inch air ratchet
1/2 inch ratchet
1/3 inch air ratchet
Oil Treatment (the thick honey like stuff in the blue and red bottle)