The process involves the use of engines that have timing chains with the oil cover in the front cover rather than the
Oil Pump. In GLC and 1979-82 626 models, the front cover oil seal may be frequently changed without try to remove the front cover. Start by emptying the cooling system and the radiator (where applicable) to ensure that there is enough clearance, but this is not necessarily required with front wheel drive GLC models. Then take out the drive belts and unscrew the crankshaft pulley. Put a small prytool carefully together with the seal out of the timing chain cover, and then completely clean the seal bore of all dirt and grease since this can cause timely failure of the new oil seal. The new seal is installed by coating the lip of the new seal with engine oil and then pushing the new seal into position with a piece of pipe, or socket, which is a little smaller than the bore of the oil pump in order to fit into the engine oil pump bore, making sure that the front edge of the seal fits into the front edge of the timing chain cover. Apply sealant on the pulley surface of the bolt, install and place the crankshaft pulley and tighten the crankshaft pulley bolt to 80-87 ft. lbs. (110-120 Nm) on the GLC or tighten the crankshaft pulley bolt to 101-108 ft. lbs. (140-150 Nm) on the 626. Lastly, attach and tighten the drive belts and in the case of an all-electric motor, replace the radiator and refill the cooling system until it fills completely with water.