GM 22530287 Exhaust Manifold

Specific steps and precautions should be followed when dealing with exhaust manifold removal and installation for different engine types. First, remove the nuts from the manifold studs to disconnect the exhaust pipe or crossover pipe, pulling the flanged portion away through a collar sliding over, occasionally needing to loosen the crossover pipe on the other side to clear it. Hot air shrouds, accessory brackets and sometimes even steering shafts of some vehicles are among parts that obstruct access and should be removed. Also, unplug oxygen sensor if available. Bend back any locking tabs on the mounting nuts, soak them in solvent to loosen them, then remove them allowing removal of the manifold and seal. The surface of the block must be fully cleaned. For 196, 231, 252 and 350 Buick Engines, raise car; disconnect exhaust crossover pipe; remove various components depending on which side you are working on. The manifold can be removed once the bolts attaching it to cylinder heads are detached. The installation follows in reverse order using lockbolts. Exhaust manifold removal in left side for 305 and 350 Chevrolet Engines involves disconnecting exhaust pipe among other things while removing right side requires removing right front wheel for access. Assemble by replacing new gasket on manifold and doing up bolts in specified sequence. Removal of exhaust pipes is part of this process as well as unbolted exhaust manifolds plus hot air shrouds among others for 350 and 403 Oldsmobile Gasoline Engines. Re-installation is done in reverse order of removal. Steps include draining cooling system, removing air cleaner; disconnecting hoses & lines; removing manifolds & adapter seal for 263 & 350 Oldsmobile Diesel Engines. Install gaskets using sealers after thoroughly cleaning gasket surfaces. Bolts should be tightened to specified torques so that they do not leak out later during operation of the engines or while driving these cars hence becoming hazardous to the users. Disconnect exhaust pipes, remove manifold bolts and clean gasket surfaces for 265 & 301 Pontiac Engines both left and right sides. New gaskets should be used during the installation and bolts tightened uniformly. Left-side removal requires certain steps including prying bolt locking tabs, unclamping the exhaust pipe and disconnecting intermediate steering shaft for the 1986-87 Oldsmobile 307 Engine. Right-side removal necessitates disconnecting oxygen sensor lead and removal of crossover pipe. Secure bolts in stages upon cleaning gasket surfaces among other things while installing them. In all cases, proper torque and sealing procedures should be followed to prevent leaks, and any sensors or components removed during the process should be reinstalled correctly.

Raise the vehicle and support it on stands, then disconnect the battery ground cable. Remove the crossover pipe and hang it from the frame with wire, followed by removing the spark plug wires from the spark plugs, marking them with tape. Disconnect the EFE pipe and remove the exhaust manifold bolts along with the manifold. Before installing the manifold, clean all old gasket material from the mating surfaces on the cylinder head and manifold. Place the new gasket into position on the cylinder head using a thin film of sealer to secure it. Install the manifold, torque-tightening the center bolts first and then the end bolts. Reinstall the remaining components in the reverse order of removal, ensuring to use a new gasket or packing at the crossover pipe flange. Finally, start the engine and check for exhaust leaks.

If the engine has been removed from the car, disregard the following steps which do not apply. For the left-hand manifold with 403 cu in or 455 cu in engine, disconnect the battery, remove the air cleaner assembly and disconnect the hot-air pipe to the manifold, and remove the hot-air shroud around the manifold. Raise the car and support it firmly on jack stands, bend back the metal retainers around each manifold bolt head, then remove each of the bolts, and disconnect the exhaust pipe from the manifold, using penetrating oil if the fasteners are 'frozen' in place. Remove the flywheel lower cover and the starter brace, wiring, and starter, then remove the exhaust manifold from under the car. For the right-hand manifold with 403 cu in or 455 cu in engine, disconnect the negative battery cable, hoist the car, and support it firmly with jack stands. Remove the right front wheel for better access, disconnect the exhaust pipe where it connects to the manifold using penetrating oil if necessary, and remove the exhaust manifold bolts before taking the manifold out from under the car. For the left-hand manifold with 260, 305, or 350 cu in engine, disconnect the negative battery cable, remove the air cleaner assembly, hot-air pipe, and hot-air shroud, then remove the generator or air conditioning brackets where they attach to the exhaust manifold. Disconnect the exhaust pipe where it connects to the exhaust manifold flange, using penetrating oil if needed, pry back the metal retainers from the bolt heads, and remove each of the bolts securing the exhaust manifold before removing it from above, noting that on some late models it may be necessary to disconnect the intermediate shaft of the steering column for better access. For the right-hand manifold with 260, 305, or 350 cu in engine, disconnect the negative battery cable, hoist the car, and place it firmly on jack stands. Disconnect the exhaust pipe where it connects to the manifold, using penetrating oil if necessary, remove the right-front wheel for better access, pry back the metal retainers from the bolt heads, and then remove each of the manifold bolts before taking the manifold out from under the vehicle. For installation on all models, the process is the reverse of removal, ensuring that new gaskets are used at the manifold-to-engine block and at each of the disconnected exhaust flanges, tightening all fasteners to proper torque specifications, adjusting all belts to the proper tension, and upon completion, running the engine to check for exhaust leaks, using a soapy-water solution brushed onto suspect areas to help find any leaks.

If the engine has been removed from the car, disregard the following steps which do not apply.

Raise the vehicle and support it on jack stands, then disconnect the battery ground cable.

Disconnect the EFE pipe (231) and remove the carburetor heat stove pipe on the 200/229 engine.

Mark each spark plug wire with a strip of coded tape (numbered 1-8) before removing them, ensuring to pull on the rubber boot and not the wire itself to avoid mixing up the order.