Doesn't sound good at all

[NOMOFO]

Well I haven't been around here in I don't know how long cuz the truck has just been so darn trouble free while dealing with other crises in life. But.....

Today out of no where starts this horrible noise that is sort of random but can't help but think of rod knock or KDP and the like.

There are no puddles, no overheating, lots of oil pressure.

So I open up the hood and check the oil which looks perfect.

One obvious problem is that the serpentine belt ( which is only about 8,000 miles old ) has a big strip raggedly ripped off the back so I'm hoping it was just the belt chunk slapping around until it flew off.

The noise did diminish sort of instantly which kind of supported that theory. So I take the bad one off and check to see that all driven components are spinning freely which they are. A little resistance on the water pump but that seems minimal and likely normal. Then I get out the barring tool and rotate the engine manually and that seems normal with no unusual noises or resistance. I then put on an old belt that I had saved and then rotate the engine again with the alternator nut so my ear is closer to any of the most suspect culprits like inside the timing gear cover and such. I might have heard a little tiny something inside the cover but am thinking that was just teeth meshing while compression is peaking and I'm in between strokes with the wrench.

So then I'm brave or stupid enough to start it and it sounds fine at idle. I then go about 10 mph for 100 to 200 feet without noise then it starts again so I go back to the driveway. I turn it off and open the hood to look for disaster but nothing obvious. Start it again and idle sounds okay but when I rev it, it sort of comes and goes.

There was no loss of performance and still runs smooth as silk.

Well it's dark now and I'm not in the best state of mind so It's time to buzz you all and start fresh in the morning.

TIA for any thoughts,

Bob

 

[CDegner]

Just as something to check, you might check your idler pulley. When they go, they can cause the belt to slip a groove and get chewed up. Since you just lost a brand new belt, I would be looking for something like that. You can also try to visually check the alignment of all your pulleys.



Don't know if this helps but it can't hurt.



Carl

 

[dodgenstein]

Totally unrelated to the belt problem, but the noise you are describing sound like the noise my truck made when my flex plate broke. Remove your inspection cover and look for metal shavings and small pieces of plate. If it is the flexplate, the cheapest ones are from Cummins,about half the price of Mopar.

 

[NOMOFO]

Thanks for the replies.

C Degner: The idler is fine, I actually replaced it with those of

those heavy duty steel ones several years ago.

Dodgenstein: God I hope you're right. While this will be a big

PIA I'm sure, it sure beats the thought of any

engine failure.

 

[skobylenski]

Speaking of the belt problem - I have the same thing, and it looks like the serpentine belt actually slips back towards the engine when the engine is running and then returns to it's normal position when you shut down - is this what y'all are seeing?



Whatever it's rubbing against must be pretty rough as I replaced my belt at about 275,000 miles, and by 280k it was really ravaged once again. Has anyone been able to come up with a solution to this mysterious problem?



CDegner - just reread your post, and I'll have to check both the idler and the alignment of the pulleys, but in the meantime, can anyone thing of ANYTHING else it could be. I'm just afraid of losing a belt and not having what I need to replace it when I'm sitting on the side of the interstate.



Scott

 

[BCook1]

Awful noise

Greetings,

I was asked to diagnose a similar sounding problem on a friends 93 CTD. A horrid sound came from the front of the engine. By using a wooden dowel as a hearing probe I found the sound to be the alternator. It was a rebuilt unit still under warrantee that should have had no problems but... . When the belt was removed, the alternator spun free but when belt tension was applied, the cooling fan inside hit on the case. The only way to get it to misbehave was on the test bench loaded. Put on a different rebuilt and the sound was gone. That was an easy fix - hope yours is that simple.

 

[NOMOFO]

Well I'm holding out for it being the flex plate because no other symptoms seem to be present. Upon opening the inspection plate there is a small amount of bright shiny fine flakes that stick to a magnet but no big chunks. A real good transmission shop is only about 2 miles away so I drove it down there today with very little noise. It sounded awful last night even at idle. This morning with the plate off it did sound like noise was emanating from that hole.

So I found a plate at Cummins West and made him aware of that.

He was grateful for that info as the $94. 22 price still is good. Interestingly as bad as the $295 price at the Dodge ste... . I mean dealer is, he showed what the Ferd Ste... I mean dealer gets

$400 for. Amazing!!! Oh well as I spend the night, sleepless, awaiting the diagnosis I will pray for all Chevy, Ford and Dodge owners who might be sweating some big failure cuz this feeling really sucks.

Thanks for all the ideas.

 

[RHancock]

Mine did this when the water pump went out, chewed up a brand new gates belt too... the easiest way I found was to put the belt on and run the motor up to high idle and watch if anything is moving around or not moving. If it is hard to see a strobe light can help...

 

[Tim1]

belt problem

Hey bud, at the risk of sounding old fashion, have you run the motor with the belt off to see if the noise related to the belt system? I know this sounds elementary, but I always start by a process of elimanation. Good luck and please post us on your find! Tim

 

[Bob Beauchaine]

It's been my experience that the problem you describe is caused by a bad pulley or a pulley that is out of alignment. Try looking at the belt from both sides to see if all pulleys are running true. The only other thing I can think of is that the belt was bad but that's a long shot. Good luck



Bob

 

[NOMOFO]

Well we're unable to pinpoint anything at this point. Noise seems to be all or mostly gone at the moment. I do think I'm noticing a developing clunk as transmission engages. I tried revving up a bit and shifting into gear with the brake on and something sure doesn't sound right there. The pulleys all run true and all components are tightly mounted and spin freely. No appearance of belt running out either. There is evidence of the belt rubbing on the bracket a little though. Ran it without belt and no difference. Ordered up the plate and timing cover gasket and crank seal but won't receive any parts before Monday so this weekend am going to go in and check on the KDP and killer mounting bolts. Hopefully I just have to do the preventive measures. Please join me in prayer.

Again thanks for all the thoughts and ideas.



Any tips on how to hold the fan pulley while trying to loosen that nut? Manual says stick screwdriver or bar between bolts to hold but there isn't much head there to wedge against. Keep slipping out with screwdriver.

 

[CDegner]

Originally posted by NOMOFO

Any tips on how to hold the fan pulley while trying to loosen that nut? Manual says stick screwdriver or bar between bolts to hold but there isn't much head there to wedge against. Keep slipping out with screwdriver.

A thin, long bladed screwdriver works well. Just remember that the threads are left-handed (turn clockwise to loosen).



Good luck and may you find nothing seriously wrong.



Carl

 

[NOMOFO]

Hallelujah!!!! Not the KDP or housing bolts!!!! Still a big WTF? but what a relief. Gaskets, seal, etc. will show up late Monday afternoon so hope to be able to put all back together Tuesday. I am going to throw in a new waterpump while it's easy. I also ordered a flex plate to have on hand because my gut feeling is that it still is the culprit.

Thanks again for all the ideas.

 

[NOMOFO]

Final tally of all problems:



1) Flexplate is bad. Amazingly the center has completely separated yet is still captivated in the center and there are other pieces that have separated but are still captivated. I understand if this doesn't make sense but I have photos that I wll post when I figure out how to do so. There are other cracks all over it originating from most of the various perforations in it. Why the **** would they build it like this??? I also have photos of how I killed the KDP with a through bolt and nylock through the cover.



2) The belt tensioner was bad. The spring portion had tilted apparently to the point where the belt was riding on the arm but to the eye like it still looked like the pulley was turning true.



3) The fan pulley bearing was clickety but I may have done that in the process of trying to beat it loose as suggested in numerous postings. I will not do that again. I will make or buy a wrench that captivates the pulley bolts to hold it while I use the fan nut wrench. (Good luck trying to wedge a screwdriver between bolts to hold it. ) I don't think that bearing is designed to take the intense point loading that beating on it must create. That bearing from Cummins is $104 and change!



Bottom line is I'm running again, new flexplate, KDP is blocked, all bolts in gear housing are Loctited and retorqued except that one housing bolt right next to the lower cam retainer that requires the cam to come out but I am reasonably confident that is good and tight. Time will tell.

Thanks for the support,

Bob

 

[Philip]

To post a pic all you have to do is make sure it is under 32k in size. Make and new post. Down towards the bottom of that new message page is a button that says "attach file" click on the browse button beside the empty box. This will show the contents of your computer HDD. Just find the file you saved the pic in and click ok till it shows the path in the box. Then submit the post as normal.