Rattling noise coming from front of engine (1 Viewer)

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I have a rattling noise that is somewhat intermittent when in park but under load sounds like a box of marbles rattling around as heard in the video. I have checked every pulley.. replaced idler and tensioner..belt.. recently had timing belt replaced with pulleys and tensioners. No noise when engine on and serp belt removed. I took everything back apart and checked everything I could for the noise and I am at a loss. No play or noise in fan bracket or clutch when removed and spinning it by hand. Anyone have any insight on this?

 
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Could one or the other belt be rubbing on a timing cover, due to someone not getting them on properly?

edit: err, missed your comment about no noise with serpentine belt removed. you shoulda saw rub marks if that was the case with serpentine. weird noises from a/c, alternator, or power steering pump dying?
 
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Looks like you said the noise goes away when the accessory belt is removed so that will help out in figuring this out.

Sounds like your fan is maybe hitting the plastic shroud although you mentioned checking that.

Just need to go over everything else that is being turned by that belt to narrow it down
 
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Could one or the other belt be rubbing on a timing cover, due to someone not getting them on properly?

edit: err, missed your comment about no noise with serpentine belt removed. you shoulda saw rub marks if that was the case with serpentine. weird noises from a/c, alternator, or power steering pump dying?
I have checked all of the pulleys and bearings and they are all tight. The sound seems to be coming from between the fan bracket and idler pulley but it could just be echoing off of somewhere else. I've tried almost everything I know to do minus throwing parts at it.
 
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I notice some tools hanging out on the intake, any chance something dropped down into the abyss and is contacting the belt?
I have checked that as well. Initially thought it was the coolant tube that connects to oil filter as it was missing the nut on the cam cover but replaced that and the noise is still there. Tapped everything with a rubber mallet and noting rattling.
 
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I have checked that as well. Initially thought it was the coolant tube that connects to oil filter as it was missing the nut on the cam cover but replaced that and the noise is still there. Tapped everything with a rubber mallet and noting rattling.

Don't start throwing parts at it, gotta be able to figure this one out. There is a radiator hose clip near the fan, any chance that could be getting hit? Just thinking out loud here. Any signs of wear on the fan blades that would maybe point to that contacting something?

Shoot, what else could it be if it goes away when the belt is off. Can't imagine a water pump, alt, or power steering making that noise. Might pay to drop the skid plate and take a look from under? Gotta be able to feel some vibrations on something, radiator, intake, anywhere where your hand won't get chopped off to try and narrow it down.
 
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Don't start throwing parts at it, gotta be able to figure this one out. There is a radiator hose clip near the fan, any chance that could be getting hit? Just thinking out loud here. Any signs of wear on the fan blades that would maybe point to that contacting something?

Shoot, what else could it be if it goes away when the belt is off. Can't imagine a water pump, alt, or power steering making that noise. Might pay to drop the skid plate and take a look from under? Gotta be able to feel some vibrations on something, radiator, intake, anywhere where your hand won't get chopped off to try and narrow it down.
I took the fan shroud out and hooked the fan back up and the noise was back. So it's not rubbing against anything. I have taken the bottom plate off and nothing there either. No signs of wear on the fan blades. I have tried spinning the fan to see if maybe the fan clutch bearing and no noise or play there either. I have torn this thing apart twice now and been on it for 2 weeks and can't find it. I wanted to take it to Bald Mountain this weekend but without this fixed I don't trust it to make a 8 hour turnaround trip.
 
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It's interesting that the noise seems to be happening faster/quicker then the belt is spinning .
I tried to get some good audio through the mechanics stethoscope but didn't work out too well. However, the sound is pretty pronounced in this spot. I don't even know what this is. Some of the swooshing sounds are coming from the stethoscope because it wasn't making that swooshing sound but the rattle was pretty clear where I had the scope in this video.

 
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Mine has a similar sound when the AC is engaged but barely audible in my case. Same type of sound though. Maybe compressor is going out?
 
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Mine has a similar sound when the AC is engaged but barely audible in my case. Same type of sound though. Maybe compressor is going out?

So to rule that out. I replaced the AC compressor bearing tonight...and the noise remains. Pretty happy I was able to get that snap ring out with compressor still installed tho. Lol
 
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I assume you put the stethoscope on the AC compressor and alternator to see if the sound was coming directly from them. The scope should localize the sound to one of the Serp accessories.
 
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I assume you put the stethoscope on the AC compressor and alternator to see if the sound was coming directly from them. The scope should localize the sound to one of the Serp accessories.
Yes. Problem is you can hear the noise through pretty much everything in that area as it's echoing off of the surrounding metal
 
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I assume you put the stethoscope on the AC compressor and alternator to see if the sound was coming directly from them. The scope should localize the sound to one of the Serp accessories.
You can hear the noise the loudest in the part I put the scope on in the video above, I am new to LCs so forgive me I don't know that part (connected to intake and throttle body). I also hear it in the idler pulley, but I replaced with a new one and the sound remained.
 
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You can hear the noise the loudest in the part I put the scope on in the video above, I am new to LCs so forgive me I don't know that part (connected to intake and throttle body). I also hear it in the idler pulley, but I replaced with a new one and the sound remained.

Any progress on this?

I wonder if there is something within the throttle body that could be the culprit? Sounds like you are slowly ruling everything else out.
 

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