How hard is it to replace water pump
Replacing the water pump is very easy. I have done it a few times. I have owned a total of four full-size GM cars; a 1992 Oldsmobile Eighty-Eight, a 1989 Buick LeSabre, a 1999 Pontiac Bonneville, and my current 2001 Buick LeSabre. Here is a description of how it all fits together. The water pump is aluminum and is bolted to the timing chain cover, which is also aluminum, and which contains the oil pump, oil pressure sending unit, and oil filter base. The timing chain cover contains three coolant passages, one inlet and two outlets. The inlet passage connects to the lower radiator hose. Since the radiator hose connects to the timing cover and not to the pump itself, you do not have to remove the hose. Each outlet passage goes to one side of the block. On 1990's models, the front engine mount bolts on over the water pump, and replacing the pump requires you to support the engine and remove the mount. 1980's models have all the engine mounts at the bottom, and 2000 and later models have the front mount bolted to the cast aluminum oil pan. Besides a new water pump and gasket, you will need Permatex High Tack gasket sealant, Permatex #2 sealant, Blue Loctite, a socket set, a gasket scraper or razor blade, a torque wrench, a drain pan to catch the coolant, and new coolant. Before you replace the water pump, flush the cooling system out in the driveway. Then drain out as much water as you can outside and push the car into the garage, or fill the radiator with water and drive the car in and drain it in the garage. Begin by loosening the four bolts that hold the water pump pulley to the pump, but leave the belt on as it will help hold the pulley still while you break the bolts loose. After you have loosened the pulley bolts, remove the serpentine belt. Draw a routing diagram if there isn't one under the hood. Now remove the bolts and the pulley. With the belt and pulley off, the pump is fully accessible. Remove the eight bolts and the pump. DO NOT loosen or remove any timing cover bolts. Some of the bolts are short and thread into the timing cover, and some are long and go clear through the cover and thread into the block. If the pump is stuck to the timing cover, first make sure all the bolts are out. If you are unsure, look at your new pump (you bought one before trying to remove the old one, right?) and observe where the bolt holes are and compare to the old pump. If the pump still won't come off, hit the edge of the drive flange (the round part that the pulley bolts onto) with a soft-faced hammer and the pump should break loose. If that doesn't work, insert a pry bar between the pump and the drive flange, NOT between the pump and the timing cover, and pull toward you. Now, you must scrape the gasket surface of the timing cover completely clean and smooth. I like to use a razor blade. A long-handled scraper is safer for you but more likely to dent or gouge the aluminum. DO NOT use a wire brush or sandpaper. While it is a little dangerous to hold a razor blade in your fingers while scraping a gasket, it forces you to work slowly and carefully. Hold the blade as flat as possible to the surface and start at the edge of the gasket, lifting the gasket off as you go. Don't try to shove the blade through the middle of the gasket. You will slip, slice your fingers, and damage the surface. OUCH! Clean the bolts thoroughly with a wire brush. Remove all traces of rust and sealant. Now check the threads in the timing cover and engine block. Clean them with a long, thin wire brush such as a gun-cleaning brush, or a tap. You will notice that the holes that go through the cover into the block go all the way into the water jacket. Sealant must be applied to these bolts or they will leak and corrode. That's why it's important to clean them. Clean the gasket surfaces of the timing cover and the new water pump with brake cleaner. Now, coat the gasket surfaces with a thin layer of Permatex High Tack. Place the new gasket on either the timing cover or the new water pump, The High Tack will hold it in place. Coat the threads of the bolts with Permatex #2. Slip a couple of bolts through the pump and install the pump, making sure the correct bolts go into the correct holes. Torque the long bolts to 22-29 ft-lbs and the short bolts to 8 ft-lbs. Reinstall the pulley, using blue Loctite on the bolts. Reinstall the belt and torque the pulley bolts to 10 ft-lbs. Refill the cooling system and you are done. I hope this helps you, and remember, don't ever be afraid to fix your own car. Just make sure you understand what you're doing, work safely, and use the right tools.
Nov 26, 2012 |
2001 Buick LeSabre