Saturn VUE

I was on my way home from a few nights ago, when my used Saturn VUE cutoff while I was driving. Had to tow it home. Next day the mechanic said the idler pulley seized up and caused the timing belt to come off track; He showed me the idler pulley that was cracked open, i could see ball bearings; after replacing the timing belt and the idler pulley the car still would operate as they suspected would happen. THey believe the cylinder head gaskets need to be replaced and that I need new valves.

a friend of mine who is a mechanic says there is no way the idler pulley could have failed and caused the belt come of track or break. My cousin who messes with engines on occasion disagrees. I also called a few other mechanics who say it is possible that the idler pulley caused damage to the timing belts and the heads.

Who’s right? Any suggestions?

None that would help so we’ll just bump it up.

Yes, an idler puller seizing could cause a timing belt to jump off track, or jump some cogs on the sprocket. If this is an “interference” engine, that could also cause some bent valve stems, requiring new valves. Replacing valves requires that the head gasket also be replaced, as the head needs to be removed to replace the valves.

In an interference engine, the pistons when all the way at the top of their strokes occupy some space in the cylinder that the valves need when they’re fully open. The timing belt synchronizes the two such that the pistons are never at the tops of their strokes at the same time that the valves are fully open. If the belt breaks, or jumps, the two can happen at the same time and the pistons bang into the valves. That can bend the valves stems.

I think your mechanic is being legit with you. And his having showed you the damaged parts is hte honest way of doing business.