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Spun bearing?

Mopar-Charger

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I saw driving home today and the car would not stay idling and I started hearing a "knock" with any gas. I got home, pulled the plugs, they all looked fine, made sure the timing was good, even retarded it a few degrees wondering if it was just ping... nope.

I can post a video if that helps? I'm worried it's a spun bearing or worse. Once I swapped the plugs, it idles fine, but again with any throttle theres a "knock" that's constant through the rpms until it goes back to idle, where you can't hear anything.

I don't have a jack at the house right now, but when I get it here I'm going to drain the pan and cry.

No silver pieces showing on the dipstick
 
Oil pressure steady? Could be anything.
 
Yeah oil pressure is steady. I pulled the valve covers and 4 of the rocker arms move side to side. #s 2 (intake, exhaust) and 8 (intake, exhaust)

Engine still turns freely. I start to hear a slight knock about 100 miles ago. Now within 20 (started while I was at school) drove home with a pretty distinct knock til I got to the driveway. Between then and now, I've started the car ran for about 5 minutes no problems and steady oil pressure. Yet there is still a "knock" with any gas given.

From what I've read, if there its a spun bearing or rod knock, the engine doesn't last any more then around the block?
 
Check for dumb ****. I had a torque convertor bolt do something similar.
 
I'll have to jack it up and check. I remember having the bolts come out a few threads. I'll have to double check. I was just thinking that.
 
There will be a difference between a "knock" and a "tick". That being said, without hearing it, we would only be guessing. An rpm sensitive knock is most likely a spun rod bearing, but there is a possibility of a cracked/broken piston skirt. Mostly depends on the tone of the knock; is it light or a solid knock? If a rod bearing did spin, keeping running it will only destroy the crank more, and possibly to the point of needing to weld it, or have to get another one. The rod is almost certainly junk, especially if the big end is black. If the big end is still cast color, it could be possible to save, just need to have it measured. The problem with trying to resize it for reuse is that the rod stretches in the 12 and 6 clock position and consequently pulls the parting line inwards, and ruins the rod.
 
grab a solid steel bar eg. socket extension or similar and place one end next to your ear and the other end on the engine block close to were you think its knocking & you should clearly hear the problem.but as 69bee said i wouldn't run it to much as you may destroy the engine
 
fingers crossed its something silly, if oil pressure is good, and the flywheel, converter, balancer arent the culprits, you most likely have a beraing issue, i wouldn't try to find it by revving the engine, lift the car, drain the oil, and look for the silver swoosh, if its not there, look at everything else, worse case drop the pan and you will know for sure..
 
Check the flex plate for cracks as well. They knock like crazy. But my bet is a spun bearing. Why? It happened along with the fact it doesn't want to idle. I personally only ever spun one bearing. Drove the car home 60 miles from the drag strip. Pressure was down 10 psi.
Doug
 
I'll post a video of it tomorrow.

The car idles fine in park, as soon as I give it gas you start to hear the knock. And the knock gets faster and faster as you rev it up.

It's completely gone at idle.

How would I go about checking for a sticky valve?
 
Check the bolts holding the crank pulley to the balancer. Mine loosened and I changed alternator , water pump and top pulley before I found it. Really felt stupid but I could not isolate the noise and it only started as I increased the idle. Dave
 
You can unload cylinders by removing the plug wire one 'ground them' at a time and see if the knock go's away or quiets out a bit to determine which is wounded.
 
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