bad gpr or glow plugs. its unburnt fuel. once you get it started use the block heater go drive it and see if the noise is gone. also ensure the metal tab on the bottom of the ebpv is bottom out on the stopper. if so drive and give us an update.

 

and just kinda oozing out like that i'd guess the ebpv at least partially shut too?

 

Update: I borrowed a truck for a few days so that I could take my time figuring this problem out. I changed the oil today, and I spent some time looking everywhere under the hood for obvious problems.

After the oil change I started the truck. It was slow to start but it finally caught and ran. The batteries seems weak so I will have them checked soon.

I have the EBPV unplugged, and noise is still there and it sounds terrible and loud. It does sound as though it is coming from the back of the engine, but it is so loud that I am afraid to let it run long enough to pinpoint it.

I did notice something new. The belt tensioner has a short arm. The bearing is worn out and the pulley is cocked back so that it is contacting the bolt at the pivot point. I bought a new tensioner assembly and the arm is longer than the existing one, so before I try to install it i wanted to find out what every else has on their truck. Is the pulley on your truck close to touching the pivot bolt or is it about 1.5" away?

Hopefully this is what is causing the noise.

 

 

Thanks TJ.

Yours looks more like the one I picked up at the parts store. This pic shows the difference in mine:



The arm is much shorter. It looked at first as if someone put the wrong part on it, but now I think it is also a case of putting the wrong pulley on the wrong assembly. As you can see, the bearing has worn out and it has allowed the pulley to bow back and make contact with the pivot bolt.



I was worried at first that this new one would be too long, but pointed up at 1:00 as yours is - it works. Hopefully mine is unique, but it would worth it for others to check this out.

I will be replacing mine tomorrow and hopefully it cures my noise problem.

 

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I didnt get that one either. I figured I would keep thinking about it and it would make sense.

 

Just wanted to subscribe to the thread and had nothing to say..

 

Thats what I figured. You can go tot he top of the screen near the search box and there is one called "thread Tools" click that and in the drop down menu there is a "subscribe" option.

 

Changed out the tensioner this evening. I started the truck (still hard to start) and the noise is still there. This time though the noise would stop and start. When it's constant the noise seems to come from everywhere, but off and on it seems like it could be coming from the front. Then rpm slows a little when the noise starts, and it actually caused the engine to stall.

It might be the idler pulley grinding, but does a bad HPOP make any noise? Im thinking that the noise and hard starting could be related.

 

I would take the belt off and start the engine then see if the noise goes away.

HPOP don't usually go bad so I doubt thats the problem. I wonder now if the fan clutch is engaging

 

While you had the serpentine belt out, did you check the idler pulleys? Depending on your options, some 7.3's have 2. There is a bushing around the bolt that went bad on mine, causing the pulley to grind into the engine block. The horrible grinding noise was intermittent with engine RPM and steering, due to the load changes from the rpm and power steering pump. I know its a long shot, just hoping for a cheap easy fix for you!

 

Its going to take a while as I am working on the truck after work and because it is in the front yard I have only a hour or so each nite to work. Luckily I have another truck to drive.

@TJBeggs

I wanted to try to start it with the belt off, but it got dark too soon, and I need to charge the batteries before attempting to start again. The fan clutch seems tight to me, but I need to watch while the truck is running.

@jkopec

That is the direction I am going too. Mine has two and i will likely replace them regardless.

 

what rpms do these trucks start making good boost mine doesn't seem to really be there until atleast 1500 rpm