Doorkicker thank you for your continued support and insight to this debacle. Flywheel bolts should be in check. Back in 2020 I installed a rebuilt 4 speed, a lighter billet steel flywheel along with new clutch and pressure plate. Torqued everything to spec and used loctite. The noise existed even before i installed the new 4 speed/flywheel/clutch. I do need to get under car and check the crank movement still. I installed new fuel pump with no luck with noise. I don't recall any pulleys interfering with anything but its worth another look. As far as the oil pump... when the motor was originally rebuilt it was done by a shop. The second rebuild me and my friend noticed there was no oil pump gasket in the gasket kit i bought. Its Melling pump. I have most definitely seen the conflicting information/opinions about gasket or no gasket. Today over on the A body forum i found someone that said go see what the Melling engineers say Or SCHUMANNS. After the second rebuild I did notice with out a gasket that my oil pressure wasn't what it used to be. There is a nice copper gasket i plan to add. I actually called schumanns and talked to them to see what there 2 cents was. Last night I was investigating about the distributor drive gear. I would be surprised it the distributor drive gear was worn tho. The first rebuild was done in 2012 is why i say that. Then after i cracked that piston in 2015 we had to rebuild it and i just did my homework and my friend and I did it ourselves. The only thing we didn't do was check the block and rods. I have a suspicion that the number 2 piston/cylinder/rod is gonna be at fault. The machine shop that checked everything installed the new KB167 piston onto the rod for me. I don't really know how they could have messed that up but that may be the case. On keith blacks website it says that the KB167's are press fit OR floating wrist pin. I"ve had several people say they think it sounds like a wrist pin. I really hope my cylinder wall on number 2 is good. The machine shop said they checked the cylinder to make sure it was still true but they kept givng me the "call me tomorrow we are almost done" and this went on for months. So i won't be surprised if its not right. My friend and I plan to drop the oil pan ( I think i can do this with motor in car still ) and just check all the rods for slop and maybe even take the cap of #2 and see if all is well. I really don't want to remove the motor thats why i am being thorough hoping i can first to find something stupid simple staring me in the face. If it comes down to it tho, its not no big deal. We have a garage and lift and all the tools to get it out. It wouldn't take us a couple hours if that to pull the motor. I can almost count in my head how many bolts it is lol Anyway until i check in again here is a walk around video of the Charger Idling.
Ok... cool... we can move away from the flywheel, fuel pump, pulleys, and drive gear/bushing.
- As for the oil pump. I'm all about the gasket because if there is a leak, well you won't know other than low oil psi. Nevertheless, if the internal and/or the outer rotors are worn badly or loose, especially the inner rotor's shaft's interface with the outer body of the pump where it goes through to engage with the halfshaft, you could get a knocking. It's interesting to note that the rate of knocking from the video seems about half the rpm. But that could just be mind tricks I'm playing on myself.
- I'm 99% certain you can get the oil pan off with the engine in the car. I do it all the time... BUT... admittedly, that's with a 440 in a B-Body. Nevertheless, do it and check the oil pump and rod ends as you suggested. My gut says it's not the rod ends only because it doesn't have that "Get me the F outta here... I'm going to punch a hole in the side of this block" sound. And you said it's been doing it for a while.
- I think there's a lot you can do before pulling the engine. Drop the pan... check everything. If you don't find anything, pull the heads. At least then you can inspect the cylinder walls, valves, and piston tops. Actually... don't pull the heads... you can get a $40 endoscope, pull the plugs and at least do a visual inspection.
- If after all this you think it's the wrist pin... you can pull the rod and piston out from the bottom. You'd need to pull the head as well, if for no other reason to reinstall them. However, that's not an insignificant knock, and it's been doing it for a while. The pistons, rods, and main... they don't just knock a little for a long time... it usually get's progressively worst... which you're not experiencing. Also, that doesn't explain why the knocking didn't go away or even change when pulling the plug wires one by one while running/revving.
- Admittedly, a wrist pin could knock... here are some ideas...
-- if it's a floating pin and they failed to install or install correctly the locking rings (which happens all the time), the pin is coming in contact with the cylinder wall. However, I do not believe this would be a consistent noise... I don't think it wouldn't be rhythmic or sound as thumpy.
-- if it's a press fit and they jacked up the heating process... they may have not centered the pin correctly. Meaning one of a couple things...
------the pin isn't centered and therefore will create sidewall pressure and eventually produce a piston slap.
------And/OR, they didn't do the heating right and then attempted to use a press to finish installing the pin (I've seen that too) and if you don't have things setup really, really well you can create interference with the piston and lock up the pin... this results in the pin locked into the rod (what you want), but also locked up in the piston (what you don't want). The pin over heats in the piston, wollers out the aluminum in the piston just enough to not over heat and creates a "stable" knock.
And one could argue the knock would persist even without spark because the piston is still moving up and down. But again... without spark there's significantly less pressure... and this is inconsistent with the knock not changing at all when you pulled the spark plug wire. Nevertheless, the compression stroke still creates pressure that could still create a knock.. but dang... there's a big difference there with no change in sound... no make sense.
I'd say pull the pan... and work your way up. You can fix this without removing the engine. I'm saying that knowing that in many cases pulling the engine is far, far easier... but I sense that may not be a great option for you.
One last thing... have you taken a long rod (wood dowel, long socket extension, etc) and put one end in your ear and the other end on different parts of the engine? If not, do that! It's super helpful. Just walk around putting the end on different places so you can hear/locate the knocking better.
And I failed to say it before, but I will now... your car looks great.
I'm getting one!
