GM 91177421 Seal,Crankshaft Front Oil

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To begin, If you want to change the front crankshaft seal, you can usually do so without removing the timing chain cover by first removing the radiator for better access to the seal. However, if clearance is too tight, you may need remove the cover as explained below. For timing chain cover removal, disconnect the negative battery cable, drain the engine oil and coolant, and remove the oil pan. Note that in some cases it may be possible to remove the front cover without having to take out the oil pan; in this case only needs removal of bolts for securing a front pan-to-cover (Linn). Remove the camshaft cover, coolant bypass pipe, bypass hose, fan, cooling shroud , fan belt and fan pulley. Also remove alternator belt , water pump pulley , alternator drivebelt tensioner , idler pulley and disconnects radiator outlet hose from thermostat housing . While not disconnecting refrigerant hoses , detach air conditioning compressor from its bracket and remove compressor mounting bracket . Use a pulley holding tool to remove the crankshaft pulley bolt and then take off pulley itself . Remove timing chain cover remembering all two dowel pin locations . To put it simply clean the timing chain cover thoroughly before inspecting front crankshaft seal for any damage after which pry out old seal with use of seal removal tool . When installing new seal , set timing chain coverage on flat surface and tap new seals into place using a large socket . Then apply RTV sealant on mating surface when reinstalling timing chain cover making sure that dowel pins are in position. Tighten down then install crankshaft flywheel bolt while holding tool on bolted pulleysRe-install air conditioning compressor bracket, alternator drivebelt idler pulley, radiator outlet hose; alternator drivebelt tensioner; water pump pulley; alternator drivebelt; fan pulley; fan belt; cooling shroud; fan. Put coolant bypass hose and pipe, camshaft cover and oil pan back. Set up cooling fan drivebelt tension, fill cooling system with coolant and add clean engine oil. Lastly, start the engine and check for any coolant or oil leaks.

Take the timing belt off, along with the crankshaft sprocket and inner belt guide. Wrap a piece of tape around the tip of a small screwdriver. Then, from underneath, use this screwdriver to wedge out that seal. Use the tip of a small screwdriver to pry the seal out carefully –wrap the tip with tape to avoid destroying the seal bore and crankshaft sealing surface. Be keen enough not to wipe or scratch either the seal bore nor crankshaft's surface. Rinse thoroughly and check for any imperfections in the crankshaft's bearing surface or sealing face. Light scratches can be smoothed using emery cloth. Installing a new seal may not cure an oil leak if there is a groove worn into the crankshaft sealing face (from contact with the seal). Trial fit one of those repair sleeves which slide over the top of your engine's bottom end crankshaft finish or upper shaft section. These are usually available at larger automotive parts stores. Make sure you lubricate your new seal with engine oil before inserting it into place using a suitable socket and hammer for driving. Insert the new seal gently by tapping it into place with a socket and a small hammer. Finally, put back all components related to timing belt. Start it up and look for signs of oil leakage.

The seal contact surface should be carefully inspected for scratches and nicks that could damage the new seal lip and cause oil leaks.

The recommended method is to remove the oil pan and the seal retainer.

The old seal can be driven out from the back side with a punch and hammer.