GM 1193966 Shedder, Crankshaft Oil

To remove and install the lower half of the rear Crankshaft Seal on Buick 231, 252, and 350 engines and Oldsmobile 307 engines, first remove the oil pan and rear main bearing cap. The old oil seal should be taken off from the cap of the bearing by applying a sealer to its groove. Thereafter use a suitable instrument to roll a new seal into the groove with both ends extending above the surface where cap parts. The working surface of the rope seal should be coated with thin film of chassis grease before being driven into the groove using a smooth tool or hammer handle such that it is not more than 1/8 inch (1.5mm) above this groove. Slightly rotate the tool to cut off those ends of seals which are flush with surface of caps using a razor blade. Soak new neoprene side seals for Buick 231, 252 and 350 engines in kerosene for five minutes, then place them in grooves on bearing caps without cutting them to fit. A sealer must be applied to mating surface of bearing cap between it and block around sealing groove. Reverse steps of removal when installing pan and cap back on. At first run engine at low rpm after new seal is installed. For upper half replacement of oil seals on Buick engines, though advised that crankshaft be removed, crankshaft may remain in place during their replacement.Loosen other crankshaft bearings so that crankshaft comes down about 1/8" (0.062 mm).Lube new seal with oil (for 1975-84 vehicles) or chassis grease (for 1985-87 vehicles) lubricate an old one.Remove excess seals if necessary.Pull each side equally.Replace all bearings; tighten all bolts according to specifications before attaching rod bolts.Chevrolet engines' oil pans, pumps and rear main bearing caps are all removed.For instance, tap upper seal slightly, and pry lower seal out through it.Clean all mating surfaces before installing new seals using a lubricator to place the lip of the seals forward.The installation tool should be used to prevent damages upon the seal by guarding the crankshaft while working around it. No oil should be present on mating surfaces so that one can replace oil pan, pump, and run engine in order to break in new seals.In case of 265 and 301 Pontiac engines, this involves removing the oil pan and baffle, rear main bearing cap, and forming a new seal in the cap.After driving the upper seal into groove on each side until it is packed tightly.Afterwards take pieces from new seal, cut them into lengths slightly longer than required to fill gaps at end of block's portion of said seal; then insert them packing these tightly.None must be trimmed. Apply a 1/16 inch bead of silicone sealer from center of gasket across to external gasket groove.Reassemble the cap and tighten bolts according to specifications before refitting oil pan.Finally run engine slowly for first few minutes so as to break in new seal.The upper oil seal can be replaced without removing crankshaft on 263, 350 and 403 Oldsmobile engines.Drain crankcase; remove oil pan and rear main bearing cap.Therefore drive upper seals on both sides till they are tight.Then cut these pieces little longer than necessary for filling grooves and stuff them into these grooves.Place shim stock between the seal and crankshaft before trimming any protruding material from surface of bearing without leaving scratch marks.Put another one in cap.Reinstall this alongside its bolts that will need specified torque values.Last but not least, refit oil pan.

Quickly roll a new seal into the groove with both ends projecting above the cap's parting surface, using a suitable tool. Apply a thin film of chassis grease to the rope seal's working surface and force it into the groove until it projects no more than 1/8 inch (1.5mm) above the groove. Cut the seal ends flush with the cap's surface using a razor blade.

Clean all sealant and foreign material from the cylinder bearing cap and case without using abrasive cleaners, and inspect components for nicks, scratches, or burrs at sealing surfaces.

Each of the five main bearing caps should be marked for their specific location in the engine block. If they are not marked, small indentations should be made similarly to the connecting rods and caps to ensure proper reinstallation.

Coil the new oil seal packing around the opening with the ends at the top.

Re-install the timing chain cover.

Install the flywheel to facilitate engine rotation during reassembly.

Use a small hammer and a brass pin punch to roll the seal around the crankshaft journal, tapping one end until the other end protrudes enough to pull it out with pliers.

Tap the end of the crankshaft with a lead hammer to align the rear bearing properly.

After unbolting the main bearing caps, each cap along with its corresponding bearing should be lifted off the crankshaft. All main bearing caps and bearings should then be placed on a workspace numbered to match their positions in the engine block.

During the final installation of the crankshaft, a thin, even film of anaerobic-type gasket sealant should be applied to the main bearing cap split-line.

Unbolt the main bearing caps and carefully lift each cap along with its corresponding bearing off the crankshaft, placing them on a workspace numbered to correspond with their positions in the engine block.

Install the flywheel to facilitate engine rotation during reassembly.

Place a drop of sealant on each end of these seal pieces and pack them into the upper groove to fill the gap made previously. Trim the remaining material perfectly flush with the block, being careful not to harm the bearing surface.

Use a punch to drive out the old oil seal and shedder, working from the front toward the rear of the timing chain cover.

Use a puller to remove the hub from the crankshaft.