Serpentine Belt Q's

[hardisk_c]

Just got finished with replacing the V-belt on my 94 GC Laredo & managed to loosen 1 of the idler pulleys (book said that one was the auto-adjuster, but mine doesn't have that) before getting at the assembly for the belt tensioner behind the power steering pump. Now that everything is back together, there's a slight metallic 'singing' noise at idle that appears to be coming from the area of the idlers. I couldn't find the torque specs for the idlers so we just tightened them down, so I'm coming here to find out what those torque settings are, or did I over-tighten the new belt? Also (this is the last part, promise) when under the hood, I noticed that the valve cover bolts were loose (no leak, just some were less than finger tight) so when attacking them to tighten them down, 1 of them snapped off (No. 6, i believe). How difficult would it be (how should it be done) to get the rest of the bolt out of the head so a new one can be inserted and how long can the vehicle be driven w/o dire consequences (I've been letting it sit in the garage so far but fam commitments have a 3k trip coming up in July)

Anyways, any help is appreciated

[bringselpup]

Snapping a valve cover bolt man, umm yeah I could believe you might have gone a bit overboard on that poor serpentine belt.

Getting that broken one out should be an easy deal actually. Get a set of bolt extractors and back it out. Even if you have to drill it and put one of those thread inserts in it's just a valve cover bolt.

[fredjacksonsan]

With the overtorque of the valve cover bolt, you'll probably benefit from getting a manual for the Jeep that shows the torque specs for tightening things.

There are kits for removing broken off bolts, basically you drill into them slightly, the bit used bites into the old bolt, and you reverse it out. You can also just drill it out with a small bit, then use a tap to scour out the remnants of the old bolt.

Keep in mind that the valve cover bolts only need to be snug enough to put a bit of compression on the valve cover gasket; you're not sealing against pressure but only drippage, and that's why it wasn't leaking when some were less than finger tight. You may have damaged the valve cover gasket so I'd think a replacement would be in order - especially since getting the old bolt out will be easier with the cover off and the old gasket out of the way. (Just be careful to keep any shavings from falling in the engine)

On the ringing noise, yeah, bringselpup is right; try loosening the bolts on the idlers a bit, then retightening until they're snug. On vehicles without a tensioning wheel, I usually just loosen the alternator bolts, let is sag until I have enough slack to get the belt off.