Hey,

I was changing the spark plugs in my girlfriends 97 Lumina today. Anyone that has changed them on a 3100 knows they are a PITA to get to in the back there. Anyway, I elected for the remove alternator route, so that involved removing the serp belt. Long story short, I put it back together and things seem to run fine, except for when the A/C compressor is running. When engaged, it makes a vibrating/humming noise. What could I have possibly done? I would think I put the belt on wrong, but it only makes noise when it is engaged....I'm puzzled.

Nobody? :(

Off topic...in hopes to save your arm next time..

Most cars like this... Remove the dog bone bolts and rock the motor forward..at least one dog bone has a hole for the bolt to hold the motor forward for plugs.

I so would have done this, but I was scared that I wouldn't be able to get them lined back up. Is this really as easy as you make it sound?

As for the A/C....it was vibrating pretty bad, so we never left it on for more than a couple of seconds. The A/C did get cold before we did this, but I am not sure about after.

The belt is routed correctly, I think the only thing that could be off is maybe it is off by a rib, but I am pretty sure it is on the pulley correctly...

Yes, remove the dog bone and “rotate” (GM’* official term for it) the engine forward. You’ll get an additional 2 – 3” at least to work. 3.1’* are easy actually. 3.8’* are a little tougher. But overall, neither are difficult.

It’* a piece of cake. You’ll be amazed that you didn’t do this sooner! Any alignment issues on re-install of bolt on either side of the dog bone can be achieved by easily moving the motor with your hand.