REMOVAL & INSTALLATION
See Figures 1, 2, 3, 4, 5, 6 and 7L6 Engine
Align engine to No. 1 cylinder at TDC before cam gear installation. The L6 engine camshaft is gear-driven. The removal of the timing gear requires removal of the camshaft. After the camshaft is removed, place the camshaft and gear in an arbor press and remove the gear from the cam. Installation is in the reverse order of removal. The clearance between the camshaft and the thrust plate should be 0.001-0.005 in. (0.0254mm-0.127mm) Refer to camshaft removal and installation section.
- Drain the engine coolant, remove the radiator hoses, and remove the radiator.
- Remove the fan belt and any accessory belts. Remove the fan pulley.
- A harmonic balancer puller is necessary to pull the balancer. Install the puller and remove the balancer.
- Remove the two screws which attach the oil pan to the front cover. Remove the screws which attach the front cover to the block. Do not remove the cover yet.
- Before the front cover is removed, it is necessary to cut the oil pan front seal. Pull the cover forward slightly.
- Using a sharp knife or razor knife, cut the oil pan front seal flush with the cylinder block on both sides of the cover.
- Remove the front cover and the attached portion of oil pan front seal. Remove the front cover gasket from the block.
- Install the front cover, first obtain an oil pan front seal. Cut the tabs from the new seal.
- Install the seal in the front cover, pressing the tops into the holes provided in the cover. Coat the mating area of the front cover with a room temperature vulcanizing sealer first.
- Coat the new front cover gasket with sealer and install it on the cover.
- Apply a bead of RTV sealer to the joint formed at the oil pan and cylinder block.
- Install the front cover.
- Install the harmonic balancer. Make sure the front cover seal is positioned evenly around the balancer. Make sure the balancer goes on evenly.
- Install the fan pulley and any accessory belts
- Install the radiator and hoses
- Refill the radiator with coolant.
- Drain the cooling system.
- Remove the radiator, fan, pulley and belt.
- Remove the fuel pump and alternator, if necessary to remove cover.
- Remove the distributor. If the timing chain and sprockets will not be disturbed, note the position of the distributor for installation in the same position.
- Remove the thermostat bypass hose.
- Remove the harmonic balancer.
- Remove the timing chain-to-crankcase bolts.
- Remove the oil pan-to-timing chain cover bolts and remove the timing chain cover.
- Using a punch, drive out the old seal and the shedder toward the rear of the seal.
- Coil the new packing around the opening so the ends are at the top. Drive in the shedder using a punch. Properly size the packing by rotating a hammer handle around the packing until the balancer hub can be inserted through the opening.
- Align the timing marks on the sprockets.
- Remove the camshaft sprocket bolt without changing the position of the sprocket. Remove the oil pan.
- Remove the front crankshaft oil slinger.
- Remove the camshaft sprocket bolts.
- Using the two large screwdrivers, carefully pry the camshaft sprocket and the crankshaft sprocket forward until they are free. Remove the sprockets and the chain.
- Make sure, with sprockets temporarily installed, that No. 1 piston is at top dead center and the camshaft sprocket O-mark is straight down on the centerline of both shafts.
- Remove the camshaft sprocket and assemble the timing chain on both sprockets. Then slide the sprockets-and-chain assembly on the shafts with the O-marks in their closest together position and on a centerline with the sprocket hubs.
- Assemble the slinger on the crankshaft with I.D. against the sprocket, (concave side toward the front of engine). Install the oil pan, if removed.
- Install the camshaft sprocket bolts.
- Install the distributor drive gear.
- Install the drive gear and eccentric bolt and retaining washer. Torque to 40-55 ft. lbs. (54-74 Nm)
Install the timing case cover. Install a new seal by lightly tapping it in place. The lip of the seal faces inward. Pay particular attention to the following points.
- Remove the oil pump cover and pack the space around the oil pump gears completely full of petroleum jelly. There must be no air space left inside the pump. Reinstall the pump cover using a new gasket.
- The gasket surface of the block and timing chain cover must be clean and smooth. Use a new gasket correctly positioned.
- Install the chain cover being certain the dowel pins engage the dowel pin holes before starting the attaching bolts.
- Lube the bolt threads before installation and install them.
- If the car has power steering the front pump bracket should be installed at this time.
- Lube the O.D. of the harmonic balancer hub before installation to prevent damage to the seal when starting the engine.
See Figures 8 and 9
If the timing chain is to be replaced, position the engine to align the timing marks at TDC (0 on the scale) with the No. 1 cylinder on its compression stroke (valves closed). DO NOT rotate the cam or crankshaft while the chain is removed.
- Drain and remove radiator.
- Remove the fan belt and accessory drive belts. Remove the crankshaft pulley.
- Remove harmonic balancer, using a puller.
The outer ring (weight) of the harmonic balancer is bonded to the hub with rubber. The balancer must be removed with a puller which acts on the inner hub only. Pulling on the outer portion of the balancer will break the rubber bond or destroy the tuning of the torsional damper.
- Remove the water pump. If the oil pan isn't to be removed, cut the pan seal off flush with the block.
- Remove timing gear cover attaching screws, and cover and bracket.
- Clean all the gasket mounting surfaces.
- Apply a bead of silicone sealer to the oil pan-to-cylinder block joint.
- Install a centering tool in the crankshaft snout hole in the front cover and install the cover.
- Install the front cover bolts finger-tight, remove the centering tool and tighten the cover bolts. Install the harmonic balancer, pulley, water pump, belts, radiator, and all other parts.
When replacing the crankshaft damper, it has been found that lightly polishing the crankshaft damper with crocus cloth will greatly ease replacement. This procedure will also assist in any future removals, as it is sometimes difficult to pull a damper even with a puller. Be sure that the polishing is not overdone, or the damper will wobble on the crankshaft.V8 Oldsmobile Built Gasoline Engines
See Figures 10, 11, 12 and 13
- Disconnect the negative battery cable.Drain the coolant. Disconnect the radiator hose and the bypass hose. Remove the fan, belts and pulley.
- Remove the vibration damper and crankshaft pulley.
- Drain the oil and remove the oil pan.
- Remove the front cover attaching bolts and remove the cover, timing indicator and water pump from the front of the engine.
- On 1977 and later models, grind a chamfer on the end of each dowel pin as illustrated. When install the dowel pins, they must be inserted chamfered end first. Trim about 1 / 8 in.(3.1mm) from each end of the new front pan seal and trim any excess material from the front edge of the oil pan gasket. Be sure all mating surfaces are clean.
- On 1975-76 models apply a sealer around water holes on the new cover gasket before applying it to the block.
On 1977 and later models:
- Clean all seal mating surfaces with solvent.
- When installing the new front cover gasket, first apply sealer to the water pump bolt hole areas of the seal and then position the gasket to the block.
- Apply RTV sealer to the junction of block, pan, and front cover.
- In positioning the front cover onto the block and gasket, press it downward to compress the seal. Then, rotate the cover left and right while you guide the pan seal into the cavity with a small prybar, as shown. Now, apply oil to the threads and install two of the bolts finger-tight to hold the cover in place. Install the two dowel pins, chamfered end first.
To install, note these points:
- When installing cover bolts, first coat them with engine oil. Tighten evenly, torquing the four lower bolts to 35 ft. lbs. (48 Nm) and the four bolts passing through the water pump to 22 ft. lbs. (30 Nm).
- Apply a high quality lubricant (an example is GM 1050169) to the sealing surface of the balancer.
- When installing the balancer bolt, torque to proper specifications. Crankshaft pulley attaching bolts are torqued to 10 ft. lbs. (14 Nm); fan pulley attaching bolts are torqued to 20 ft. lbs. (27 Nm).