Your best bet on this one is to invest in a repair manual as there are a number of steps to follow as well as torque spec's. You can also find online manuals to download for free.
The engine has a harmonic balancer on it, but if it is off, it is easy to re-install. Simply line up the key and tap it on most of the way and torque down the center bolt.
Harmonic balancer replace
To change the harmonic balancer on a 1999 Pontiac Montana, first, disconnect the battery and remove any obstructions, such as the serpentine belt and crankshaft pulley. Use a harmonic balancer puller to carefully detach the old balancer from the crankshaft. Once removed, clean the crankshaft and install the new harmonic balancer, ensuring it is properly aligned. Finally, reassemble any removed components and reconnect the battery.
Remove the belt. Remove the bolt that attaches the harmonic balancer. Rent or purchase a harmonic balancer puller. Follow the Instructions with the puller and remove the old balancer. Install the new balancer making sure to line up the keyway, a little oil helps. Put the retaining bolt back in and tighten to manufacture specs.
It is on the left side of the timing cover behind the harmonic balancer, when you slide up under the front of the truck.
You can go to a local parts place and rent a chrysler harmonic balancer puller. I just did mine on a 2001 and it costed 75.00 and when I was done they gave me my money back. It is the only way to get it off.
no it;s behind the harmonic balancer take off passenger right front tire and you can get at it. you will need a wheel puller to pull the harmonic balancer off
Harmonic balancer
The CPS is located on the front of the engine attached to the harmonic balancer on the front of the crankshaft.
It is bolted to the bottom left side of the timing cover / behind the harmonic balancer.
It is bolted in the passenger side of the timing cover, Behind the harmonic balancer.
You need a socket to fit the holding nut and a large gear puller. Instructions are in the manual for the vehicle.