How do you replace the serpentine belt on a Pontiac Grand Am?

Answer 1

ANSWER for 3.1L V-6If you have the 3.1 Liter V-6, it is more complicated.

Ok, here goes. First, buy, rent, or pay the deposit on the parts store's loaner long-handled serpentine belt tool. It has skinny sockets that you will need to replace the tensioner. Bite the bullet and get the tool. Also--bite another bullet and buy the tensioner when you buy the belt. Get the best quality belt and tensioner you can get: this is NO time or place to go cheap.

If your serpentine belt BROKE, you likely have a greater problem than a worn belt. Before going to the parts store, check to see if the water pump or AC compressor is frozen up. Buy parts accordingly. The forces involved in breaking the belt will also tear the pulley on the tensioner to pieces. Just go ahead and replace the tensioner pre-emptively. That's why you bought it when you bought the belt, so do it now.

Now, grit your teeth and accept the fact that you have to remove all the moter mount stuff. You'll have to support the engine (with a jack on a 2x4 to spread the weight) from underneath. You'll remove the 3 nuts (don't lose the blind bolt under the 3rd nut) on the top of the black stamped steel bracket, the two bolts in the passenger side fender well that hold the bottom of the 2nd stamped steel bracket, the two bolts holding the heavy duty silver bracket, and the three bolts holding the heavy black cast bracket to the underside of the heavy silver bracket.

You will find that getting the 3/8" drive of a ratchet into the slight space offered by GM at the tensioner may be impossible. However, there is a 19mm flat-sided boss on the tensioner facing the front of the car. You can get a 19mm open end wrench, or a Crescent wrench, onto that boss and lift forcefully to turn the tensioner. Turn counterclockwise, as viewed from the passenger side, to loosen the belt. I would still opt to get the serpentine installation tool set from the parts store. (I also went ahead and made a 3/8" tool with more offset than the store-bought one. If you have welding capability, it's worth it to have the home-made tool.)

Since you have removed all the motor mount stuff removed already, this is the time to remove and replace the tensioner. Just do it. A good new one (a Dayco brand tensioner) is about 50 bucks at a parts store. By now you'd pay three times that not ot have to do this job again. So just do it. Considering the work you are going through to do all this on your day off, replacing the tensioner as a preventative measure is well worth it. You need skinny hands to get the bolt started, but it can be done without too much grief. Put some Never-Seize on the bolt threads before installation. Note that you have to engage the pin on the tensioner into the hole in the engine timing gear cover before tightening down the bolt. Use the NEW BOLT that will come with the tensioner: it's different than GM's.

You already have removed the black stamped steel brackets that were attached to the fender, right? And you have also removed the heavy silver one that has the three big bolts (15 mm heads, two toward the back and one toward the front) and one empty hole at the front of the silver piece. You have replaced the tensioner because you do not want to go through this again next Spring. To install the new belt, you must LOOSEN the three bolts on the heavy and thick black cast and forged bracket that is attached to the engine. They are low and toward the front. This heavy forged thick bracket was attached to the thick silver piece with the three heavy bolts, and it is the black piece that prevents you from simply installing the belt around the Power Steering pump pulley. (BTW, removng the power steering pump won't help you--you have to get the belt around the black bracket.) By LOOSENING the three bolts in the heavy black bracket, you can just barely cause a gap at the rearmost heavy bolt location between the stamped steel engine mount boss and the heavy black bracket that will just barely allow you to slip in the belt. You may need to do a little gentle levering, but don't break anything. Note that I said LOOSEN--if you remove the three bolts you'll have coolant all over the place. Even so, you may have to remove the upper one completely to get enough of a gap at the rear for the belt to go through.

Once the belt is "through the loop" of the heavy black bracket, be sure you also get it around (over) the power steering pully, under the water pump pulley, and headed down toward the AC pulley. Tighten the three bolts that you just loosened, and thread the belt on to the pulleys. It goes (ribbed side) back around the alternator, down and around the crank pulley (ribbed side), up and around the tensioner (smooth side), down and around the AC pulley (ribbed side), up and around the water pump pulley (smooth side), over the power steering pump pulley (ribbed side) and rearward to the alternator (ribbed side.) Whew! You'll quickly find that it won't voluntarilty go over the alternator pulley unless you relieve the tensioner. Use the tool you rented or bought or made to relieve the tensioner (see above), slip the belt over the alternator pulley (ribbed side), and then ease up on your death grip on the tensioner tool to allow the belt to tighten itself.

CHECK ALL THE PULLEYS to be SURE the ribbed surface is centered on each ribbed pulley!! Misalignment will break the belt in a hurry, and then you can do this delightful task all over again.

Ok, that was all easy. You started at 10:00 thismorning and now it's 8:30 tonight. Now it's time to reassemble this beast. Whether today or tomorrow is up to you.

You will find that dealing with the motor mount pieces is a challenge, especially in re-assembly. The one and only nice thing GM did for you is to have provided that 4th hole (the empty one) in the silver bracket--it allows you to pry and wiggle the motor mount pieces into alignment. Be prepared to adjust the engine up, down, front, and back a lot. With patience and some jockeying around, it all bolts together in reverse of disassembly.

Check for tools and anything you may have forgotten to tighten. The only left over part should be the original GM tensioner attachment bolt and the old tensioner, both of which you replaced with the new tensioner. Check coolant level. and Voila !!

AnswerNear the top of the belt is a spring-loaded belt tensioner with a pulley attached to it. Using the proper wrench, pry it back and the tension will relax so you will easily remove the belt. Look at how the belt travels across the pulleys first so you know how to put the new belt on.