GM 25522648 Cover Assembly, Engine Front

Follow the procedures under the heading 'Small V8' by draining the radiator, disconnecting the upper and lower radiator hoses along with the heater return hose at the water pump, and removing the fan, fan pulleys, and belts. Disconnect the fuel lines, plug them, and remove the fuel pump, then take out the alternator and brackets. Remove the distributor, marking the position of the rotor if the timing chain and sprockets are not disturbed. Loosen the front clamp on the thermostat by-pass hose and slide it rearward, then remove the harmonic balancer bolt and washer, followed by the harmonic balancer. Take out the bolts attaching the timing cover to the cylinder block and the two bolts connecting the oil pan to the timing cover, then remove the timing cover. Clean the timing cover thoroughly, ensuring all old gasket material is removed and the surface is undamaged. Before re-installing, remove the oil pump cover and pack petroleum jelly around the oil pump gears to prevent air space, then re-install the pump cover with a new gasket and torque the bolts to specifications. Ensure the gasket surfaces of the block and timing cover are smooth and clean, then install a new gasket on the cover. Lubricate the harmonic balancer shaft where it will go through the timing cover seal to prevent damage upon engine start. Engage the dowel pins on the block with the dowel holes in the cover and position the cover against the block. Apply sealer to the bolt threads and tighten the bolts to specifications, then install the harmonic balancer, bolt, and washer, using a screwdriver or similar tool to lock the flex plate or flywheel starter teeth before torque-tightening the harmonic balancer bolt to specifications.

If the engine has been removed from the car, disregard the following steps which do not apply. Begin by removing the torsional damper, followed by the water pump. Next, take out the crankcase front cover attaching bolts and remove the front cover from the engine. For big-block Mark IV engines, after removing the attaching bolts, draw the cover slightly away from the engine, cut the oil pan gasket flush with the engine block, and then remove the cover. Upon installation, ensure that the block and crankcase front cover are clean. Use a sharp knife to remove any oil pan gasket material at the oil pan to engine block junction. Apply a t-inch bead of silicone rubber sealer to the joint formed at the oil pan and block, as well as the front lip of the oil pan. Coat the cover gasket with a non-setting sealant, position it on the cover, and loosely install the cover by first installing the top four bolts and then two 3/4-inch-20 x 1/2-inch screws at the lower cover holes. Apply a bead of silicone sealer on the bottom of the cover, install it, and tighten the screws alternately and evenly while aligning the dowel pins. Remove the two ¾-inch-20 x 1/2-inch screws and install the remaining cover screws, then follow the removal steps in reverse order for the remaining components. For Mark IV V8, ensure that the block and crankcase front cover are clean, cut the tabs from the new oil pan front seal if applicable, and install the seal to the front cover, pressing the tips into the holes. Coat the gasket with a non-setting sealant and position it on the cover, then apply a t-inch bead of silicone rubber sealer to the joint formed at the oil pan and block. Install the cover attaching screws and torque tighten to the specified value. Coat the front cover seal area of the torsional damper with engine oil, place the damper in position, and use a suitable bolt and spacers to draw the damper into position before installing and torque tightening the damper retaining bolt, taking care not to damage the damper. Finally, install the accessory drive pulley and the remaining components in reverse order.

The general steps for removing and installing parts on Buick engines during maintenance procedures include draining the cooling system, removing the radiator, fan, pulley, and belt. Additional steps may involve removing the fuel pump, alternator, distributor, thermostat bypass hose, harmonic balancer, timing chain-to-crankcase bolts, and oil pan-to-timing chain cover bolts, depending on the specific task.

For big-block Mark IV engines, remove the attaching bolts and draw the cover slightly away from the engine, cutting the oil pan gasket flush with the engine block before removing the cover.

Remove the fan, fan pulleys, and belts.

Insert the hub through the cover seal and position the cover on the block as the hub slides onto the crankshaft.

Apply engine oil to bolt threads and loosely install two bolts to hold the cover, then install the dowel pins with the chamfered end first, followed by the water pump with a new gasket.

Take out the distributor, ensuring to mark the position of the distributor rotor if the timing chain and sprockets remain undisturbed.

Coat the new cover gasket with RTV sealant and position it on the engine.