serpentine belt

[amsoilman]

my 2000 montana continues to eat/throw belts. i've replaced both idler pulleys, and the tensioner. help.

[Glen_T]

I recall another thread that mentioned that the harmonic balancer on the crankshaft can deteriorate, and the pulleys no longer align...I'd examine the crank pulley/balancer for damage and/or rubber becoming visible.....Glen

[amsoilman]

glen,

thanks for your reply. the general consensus seems to point to the harmonic balancer. wish it were as easy to r&r as the one on my '64 chevy p/u.
thanks.

[Glen_T]

Yep, understand....I seem to recall that if you jack up the FR wheel and remove the small splash shield, you can get to the bolt relatively easily.....good luck! Glen

[amsoilman]

don't know if it's wishful thinking, or if it's actually the culprit. do you remember if a impact wrench is required? how about a puller?

[1999montana]

Originally Posted by amsoilman

...do you remember if a impact wrench is required? how about a puller?....

I had our van up on stands about two weeks ago to replace the lower control arms. With the right side splash shield removed, you get a good visual of the harmonic, but there appears to be only about 3 to 4 inches of clearance between the face of the harmonic and the frame rail. May not be enough to pull it out the front of the engine. I don't know for sure.

I don't know if you have to lower the engine in order for the harmonic to clear the frame or not. If I was doing this myself, I would probably figure it out based on easiest approach.

The impact would be nice, but a straight bar (also know around here as a Johnson bar) and an extension will remove the bolt in the front of the harmonic. The puller is a must. Replacing the new harmonic should be a lot easier.

Remember to replace the front seal and grease the harmonic where it touches the seal to make sure the thing doesn't run 'dry' at start-up.

['97ventureowner]

Originally Posted by 1999montana

Remember to replace the front seal and grease the harmonic where it touches the seal to make sure the thing doesn't run 'dry' at start-up.

While I haven't removed or replaced a harmonic balancer on one of these vehicles...yet, I remember back in the day when doing so on SBCs they sold a "kit" that was a chrome sleeve that fit on the harmonic balancer where it went through the cover. You lightly sanded down the part on the harmonic balancer that went through the cover, we used to call it the "nose", and there was a special adhesive that was applied to the "nose". The chrome sleeve was then placed over the nose, thus "renewing" the surface of the nose. The purpose of doing this was to ensure no oil leakage from the front seal after reassembly. The "nose" of the harmonic balancer upon further inspection would have grooves and scratches on the surface, and renewing that surface was supposed to prevent problems, along with replacing the front seal. Together they worked to keep an oil leak from occurring.As I remember , the chrome sleeve kit didn't cost that much money and was a good "inexpensive insurance policy" against oil leakage after reinstalling the harmonic balancer.

[amsoilman]

o.k., thanks for all the good advice. i've replaced the harmonic balancer, and the belt now rides true on the idler directly above it. however, at idle i noticed a stumble/hesitation every so often. as far as driveability, the shift points are different, and it does not pull cleanly through the gears. the hesitation at idle seems to be gone though. is the sensor adjacent to the balancer counting rpm for the at? any thoughts?

[1999montana]

Originally Posted by amsoilman

o.k., thanks for all the good advice. i've replaced the harmonic balancer, and the belt now rides true on the idler directly above it. however, at idle i noticed a stumble/hesitation every so often. as far as driveability, the shift points are different, and it does not pull cleanly through the gears. the hesitation at idle seems to be gone though. is the sensor adjacent to the balancer counting rpm for the at? any thoughts?

The sensor you are referring to is called a Crank Position Sensor or CPS. It tells the computer when to fire a particular coil pack for each revolution and which cylinder is at or about to reach TDC. Like the old electronic distributors from years back. The CPS is known to cause stalling, inability to start and drivability problems. Wouldn't have hurt to replace it with the harmonic out. Ya, I known, hindsight has 20/20 vision.

PS - Can you share with us how you removed the harmonic so we all know how you did it?