Cadillac 12681275 Arm Assembly, Exhaust Valve Rocker

You can Select Your Vehicle to check if 12681275 fits your vehicle.

Lift the valve covers off the cylinder heads and take out the camshafts out of the engines. Mark each of the rocker arms so that they are returned to the same position as they were removed from the engine and lift each rocker arm from the engine. After the rocker arms had been taken off, the lash adjusters were lifted from the cylinder head. In case any rocker arms or adjusters that have been used have to be reused, then they must be put back on the engine as they were. Visually inspect each rocker arm for signs of wear and stress, cracks and any other signs of damage and in the area where the valve stems touch the rocker arm. Check the condition of the rollers, they should not bind and should not be rough, if the bearings of the rollers are worn or damaged then the whole rocker arm will need to be replaced. It should be remembered that there is no valve adjustment on these engines, and therefore a worn or damaged valve train can quickly lead to excess valve clearances, which makes the valves noisy when the engine is running. Finally is the rocker arm pivot support pedestal; check for any crack or any form of noticeable damage. Verify that the oil passage hole is open in each lash adjuster, and that there are no sharp edges, or burrs, on the bottom of the adjuster. Spray some camshaft/adjuster pre-lube on the area of the pivot pocket, on the roller and on the part of the slot that touches the valve on the specific rocker arm. Pour fresh engine oil into the bores for the lash adjusters and then fit these into the cylinder head, placing the rocker arms on to the adjusters. The rest of installation is actually the reverse of removal. The oil should be changed and a new oil filter fitted before starting and running the engine and before disconnecting.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

To remove the valve covers from the cylinder heads, first loosen the rocker arm pivot bolts one at a time and take out the rocker arms and bolts, followed by the pivot support pedestal if equipped, ensuring to keep track of the rocker arm positions for reinstallation. Store each set of rocker components in marked plastic bags to maintain their original locations, noting that the 7.0L (LS7) engine does not use pivot support pedestals and that the intake rocker arms are offset while the exhaust rocker arms are not. Next, remove the pushrods and store them separately to avoid mixing them up, paying attention to the arrow indicating the front of the engine. Inspect each rocker arm for wear, cracks, and damage, particularly at the contact points with the pushrods and valve stems, and check the pivot bearings for binding or roughness, as worn bearings will necessitate replacing the entire rocker arm. Additionally, examine the rocker arm pivot support pedestal for cracks and ensure the hole at the pushrod end of each rocker arm is clear. Inspect the pushrods for cracks and excessive wear, ensuring the oil hole is not clogged, and roll each pushrod across a flat surface to check for bending. For installation, lubricate the lower end of each pushrod with clean engine oil or assembly lube and reinstall them in their original locations, ensuring they seat completely in the lifter socket. Apply engine assembly lube to the ends of the valve stems and upper ends of the pushrods to protect mating surfaces during initial start-up, then apply clean engine oil to the pivot shaft and bearing of each rocker arm before loosely installing them in their original locations without tightening the bolts. Rotate the crankshaft until the number one piston is at TDC, then tighten the intake valve rocker arms for cylinders 1, 3, 4, and 5, and the exhaust rocker arms for cylinders 1, 2, 7, and 8, ensuring each rocker arm bolt is tightened to the specified torque. Rotate the crankshaft 360 degrees and tighten the intake valve rocker arms for cylinders 2, 6, 7, and 8, and the exhaust rocker arms for cylinders 3, 4, 5, and 6, again ensuring proper torque. Finally, install the valve covers, start the engine, and listen for any unusual valve train noises while checking for oil leaks at the valve cover gaskets.

To take out the valve covers off the cylinder heads, first, do the bolts of the rocker arm pivot one at a time and get the rocker arms and bolts out and then the pedestal that supports the pivot of the rocker arm and make sure to record the positions of the rocker arms for future use. Another way is stacking each set of rocker component to be kept in the marked plastic bags to know its place of keeping. After that, get rid of the pushrods and put them aside in various batches so they do not get interchanged in usage with the correct orientation of the arrow that signifies the front of the engine. Visually examine the side of each rocker arm for wear, cracks and other signs of damage especially around the contact point with the pushrods and at the contact area of the valve stem contact point and also visually inspect the pivot bearing for binding or roughness as the bearing indicates that they must be replaced with the whole rocker arm. In the same way, check for cracks on the rocker arm pivot support pedestal; and on the other end of the rocker, ensure that the hole at the pushrod end is clear. Exploring the pushrods for cracks or signs of excessive wear and to make sure the oil hole of the pushrod is not blocked you should roll them on a flat surface to feel if they are bent. To reinstall them, apply clean engine oil or assembly lube to the lower end of the respective pushrod as well as to insert it back to its intended position the pushrod must fully seat into the lifter socket. Coat the valve stems and the upper ends of the pushrods with engine assembly lube to help in protecting mating surfaces during the first run; coat the pivot shaft and bearing of each of the rocker arms before loosely inserting them and without tightening the bolts. Turn the crankshaft to have the number one piston at TDC then torque the intake and exhaust valve rocker arms for cylinders 1, 3, 4, and 5 and the exhaust rocker arms for cylinders 1, 2, 7 and 8 as per their torque specification. Turn crankshaft 360 degrees and torque intake valve rocker arm for cylinder 2, 6, 7 and 8, and exhaust valve rocker arm for cylinder 3, 4, 5 and 6. Last, replace the valve covers and switch on the engine to check for any abnormal sound from the valve train part also you should look for oil leaks at the gaskets of the valve covers.

A special camshaft holding tool (GM# J-44221 or equivalent) is required for this procedure. After removing the cam sprocket, do not rotate the crankshaft to avoid incorrect timing and potential engine damage. Begin by removing the valve cover and the spark plugs to facilitate engine rotation. Rotate the engine until the sprocket alignment marks are aligned with a dark chain link, ensuring the nats at the rear of the camshafts are facing up. Remove the camshaft sprocket bolts and carefully detach the sprockets from the camshafts, taking care not to remove them from the chain and suspending them to prevent the chain from coming off the crankshaft sprocket. Check the camshaft caps for markings and mark them with paint if necessary before removal. Remove the camshaft cap bolts gradually until they can be taken out, then extract the camshafts, keeping them separated to avoid mixing them up. The rocker arms and lash adjusters can be lifted out if needed, and these parts should be laid out in order for reinstallation. After cleaning the camshafts, inspect each for scored journals, heat discoloration, score marks, chipped areas, pitting, uneven wear, damaged locator pin slots, and damaged threads. Measure the bearing journals with a micrometer to check for excessive wear or out-of-round conditions. Compare the camshaft lobe heights by measuring each lobe with a micrometer, recording the measurements for both intake and exhaust lobes separately; if the difference exceeds 0.005 inch, the camshaft should be replaced. If removed, soak the lash adjusters and rocker arms in clean engine oil before reinstalling them in their original locations. Coat the camshaft with clean engine oil and place it in the correct position in the cylinder head, then install the camshaft holding tool. Install all camshaft caps in their original locations and hand tighten them, then evenly tighten the caps to the specified torque, working from the center out. Remove the holding fixture, place the sprockets onto the camshafts, and tighten the bolts to the specified torque. Using a large breaker bar and socket on the crankshaft pulley bolt, rotate the crankshaft 720 degrees and re-check the sprocket and chain alignment, ensuring the darkened links align with the sprocket marks; if resistance is felt while turning the crankshaft, stop immediately to diagnose the issue. Finally, install the spark plugs and the valve cover.

Eliminating the components should be done by first unclipping the cable from the negative terminal of a battery. Then, take off the valve cover(s) to start doing the change process as shown below; The 3 bolts of the rocker arm mounting will be loosened one by one beginning with the drivebelt end of one cylinder head without removing them all; then the rocker arms, pivot balls, and pedestals must be separated, taking careful to stock all the parts of the rocker arm individually in accurately identified plastic bags for correct refitting. The rocker arms have a pedestal mount which is secured by a metal sleeve; the parts are in more or less integrated in assembly where the bolt can be tapped out. Take out the pushrods and keep them separately using a perforated cardboard box since the intake and the exhaust pushrods may differ in size and in terms of their colour. Check rocker arms for signs of wear, cracks or damage; also check that the rollers slide smoothly, and that the holes in the pushrod ends are open. Inspect push rods for any cracks, etc., and to look for any bending try to roll them over a flat surface. For reassembly apply clean engine oil or moly-base grease to the lower ends of the pushrods and replace them on the engine block where they belong so that they snap firmly in the lifter socket. Suffice it to say that it is customary to apply moly-base grease before the engines are started on each valve stem and upper end of the pushrods, and apply clean engine oil to the pivot balls and bearing surfaces of each rocker arm prior to the oil pressure coming up. Install the rocker arms, the pivot balls; pedestals and bolts fasten them to the standard torque limit before ensuring the pushrods engage and the correct positioning of the projections on the pedestals. Last but not the least; fit back the valve covers, turn on the engine and look for any dripping of oil or any noises coming from under the valve cover.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

Eliminating the components should be done by first unclipping the cable from the negative terminal of a battery. Then, take off the valve cover(s) to start doing the change process as shown below; The 3 bolts of the rocker arm mounting will be loosened one by one beginning with the drivebelt end of one cylinder head without removing them all; then the rocker arms, pivot balls, and pedestals must be separated, taking careful to stock all the parts of the rocker arm individually in accurately identified plastic bags for correct refitting. The rocker arms have a pedestal mount which is secured by a metal sleeve; the parts are in more or less integrated in assembly where the bolt can be tapped out. Take out the pushrods and keep them separately using a perforated cardboard box since the intake and the exhaust pushrods may differ in size and in terms of their colour. Check rocker arms for signs of wear, cracks or damage; also check that the rollers slide smoothly, and that the holes in the pushrod ends are open. Inspect push rods for any cracks, etc., and to look for any bending try to roll them over a flat surface. For reassembly apply clean engine oil or moly-base grease to the lower ends of the pushrods and replace them on the engine block where they belong so that they snap firmly in the lifter socket. Suffice it to say that it is customary to apply moly-base grease before the engines are started on each valve stem and upper end of the pushrods, and apply clean engine oil to the pivot balls and bearing surfaces of each rocker arm prior to the oil pressure coming up. Install the rocker arms, the pivot balls; pedestals and bolts fasten them to the standard torque limit before ensuring the pushrods engage and the correct positioning of the projections on the pedestals. Last but not the least; fit back the valve covers, turn on the engine and look for any dripping of oil or any noises coming from under the valve cover.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

You can start by removing the rocker arms, which will be loosened and stored in containers labeled as rocker arm support bars. Keep their different pushrods separately. If necessary, inspect each rocker arm for damage on the pivoting area and cracks or wear on the bearing surface; after that replace any defective ones, making sure roller bearings rotate freely. Look at the pushrods to see if they have cracks, are too worn out or bent. For reinstalling, lube the push rods and put them back into their original position with full seating in the lifter being noted. After that, place back the rocker arm support with arrows up and also wipe off grease from valve stems and ends of pushrods. Then fit all rocker arms one by one, lubricating roller bearings lightly and tightening the rocker arm bolts evenly according to a specified torque. Lastly, you can start your engine up and check it for oil leaks or noises from the valve train mechanism.

Removing of valve covers from the cylinder heads is to be done by first of all removing one at a time each Rocker Arm Pivot Bolt and taking out the rocker arms, bolts and pivot support pedestal. Keep track of their positions and store them separately. Proceed by removing the pushrods, keeping them in sequence as they are. Each rocker arm has to be checked for wear, cracks, damage as well as binding and roughness of the pivot bearings during inspection. The rocker arm has to be replaced if its bearings are worn or damaged. Also examine the rocker arm pivot support pedestal for any cracks. Make sure that all the pushrods are open at the hole on each of their rocker arms' ends and check them for fractures, large amounts of wear or obstruction in oil holes. After lubricating them with clean engine oil or assembly lube, put back the push rods exactly where they came from. In order to protect the stems of valve along with pushrod ends from damage apply some engine assembly lube on them. For every rocker arm shaft as well as bearing make sure you apply clean engine oil then install loosely into original locations (where they were removed). Rotate crankshaft to TDC on compression stroke for number 1 piston then tighten intake valve rocker arms for specific cylinders. Rotate crankshaft 360 degrees then tighten intake valve rocker arms on other cylinders. At last put on valve covers start engine and listen for unusual noise coming from valve train and to check for oil leaks.

The first step is to loosen the rocker arm pivot bolts one at a time and take out the rocker arms and bolts, followed by the pivot support pedestal.

Before starting the engine, change the oil and install a new oil filter.

If a rocker arm is worn or damaged, the entire rocker arm will need to be replaced.

Detach the valve covers from the cylinder heads.

Apply engine assembly lube to the ends of the valve stems and upper ends of the pushrods, then apply clean engine oil to the pivot shaft and bearing of each rocker arm.

Apply moly-base grease to the valve stems and pushrod ends before positioning the rocker arms.

Detach the valve covers from the cylinder heads.

The rocker arms and lash adjusters can now be lifted out, and it is important to keep these parts organized for reinstallation.

Lubricate the lower end of each pushrod with clean engine oil or assembly lube.

If a rocker arm is worn or damaged, the entire rocker arm will need to be replaced.

Compare the camshaft lobe heights by measuring each lobe with a micrometer, recording the measurements for both intake and exhaust lobes separately; if the difference exceeds 0.005 inch, the camshaft should be replaced.