harmonic balancer arching???

I just noticed it sounding a little wierd at idle when I pulled into work today, so when i got home I took a peak under the hood. It sounds like the E-fan is going out, so I unplugged it but the rattly sound came back. Then I heard this little "tick" sound every so often, and after looking around I noticed that there was a spark coming off the harmonic balancer whenever I heard the "ticking" sound. Has anyone heard of this and know what might cause it? Nothing is touching it, and It was replaced about a year ago. Like I said, its been fine up till today when I noticed it, and it didnt seem to miss a beat while driving it home. Its on a 97' 4.0 that I swapped into an little over a year ago. I searched, but didnt find anything.

Thanks,
Jacqui

That spark is the mechanical fan hitting the balancer. either it is bent, your fan clutch or fan pulley bearing is shot and letting the fan wobble, or the balancer is separating.

Ok, I unplugged the e-fan which is what i thought was the culprit, but the rattly noise is coming from the water pump pulley right in front of it. But it only makes the noise when the a/c compressor kicks on. Soooo forgive my stupidity right now, but does that mean its a belt tension issue, a pulley issue, or both?

I did some more searching online and found some stuff on belts that can cause sparks every so often due to static. Everything is leading me to believe it would be a belt issue...but I wouldnt think the pulley would make noise would it?

Thanks again

I've had the same static problem before with a new belt. It's weird but should go away after it breaks in a little.

If your belt is too loose it will slip when the AC turns on but will make more of a screeching noise. Belt tension shouldn't make a rattle noise but it wouldn't hurt to check your belt tension anyway. It's probably a bad bearing somewhere possibly your water pump since it's making the noise.

My belt doesnt screech at all, and I just replaced the water pump about 6 months ago...Im pretty sure the rattle is coming from the PS pump, but will check again in the morning and post up what i find (or hear).

remove belt.
Spin all pulleys by hand and try to wiggle them. Find accessory that doesn't spin smoothly, replace.

87manche said:

remove belt.
Spin all pulleys by hand and try to wiggle them. Find accessory that doesn't spin smoothly, replace.

Click to expand...

X2 that is the only effective way I know to find a bearing noise