OK, this continues to drive me crazy, need your ears, it won't be easy

[Tboggus]

After years of chasing it is almost worth it to pull the thing and stick it on a dyno so you can stand next to it and put your head against the valve covers or oil pan.  I've had some really crazy stuff make noises - windage trays and the flat tin under an intake will amplify the smallest contact and make it sound horrific.  I've had rockers touch an otherwise well clearanced valve cover in one spot, I've had one rod bolt touch a tray, I've had a single broken inner valve spring, I've had the dipstick wrap up, I've had a fuel pump with a broken return spring, I've had a roller lifter tie bar hitting the block, I've had worn rockers clip on a valve tip - - seems like I've found every one of them only after eliminating a million other items....

Had a knock in an truck and finally figured out the passenger side rear view mirror was loose...  Would have sworn it was a piston skirt or wrist pin.

[My427stang]

I will let you guys know.  So far everything thought of has been checked, magged or changed.  I am putting together a little long-rod 396, I am going to swing that in for the summer after I do the plug wire check, although I have never done that method other than idle, at this point it could ID a piston noisy under load.

Might have missed it, but yes, pins were all mic'd, small end measured, pistons visually inspected.

I never say never, but I am sure it is in the engine, there is nothing loose on the truck and it follows tach, is repeatable and it's had so many configurations of parts it has to be in the long block itself.  I am really leaning toward a cracked piston, but heck, you'd think I'd have seen something in three separate assemblies..

Sorry to have let this run so long without more info, but out of town for a few days, I will update Sunday or Monday

[plovett]

I hope you find it.  I imagine it'll be a relief to know, regardless of what it is or how serious it is. 

[My427stang]

I hope you find it.  I imagine it'll be a relief to know, regardless of what it is or how serious it is.

Thanks Paulie, honestly I couldn't care less if it was serious. LOL  In fact, I couldn't imagine a part in the engine I wouldn't happily replace and hang the broken one on the wall or happily spiral into the trash.. Now it's my Moby Dick. 

[plovett]

I hope you find it.  I imagine it'll be a relief to know, regardless of what it is or how serious it is.

Thanks Paulie, honestly I couldn't care less if it was serious. LOL  In fact, I couldn't imagine a part in the engine I wouldn't happily replace and hang the broken one on the wall or happily spiral into the trash.. Now it's my Moby Dick. 

I forgot what your rank is, but it'd be cool to call you Captain Ahab.   

[blykins]

Sometimes it's what we least expect....

Dad bought a new Harley and I had Lunati grind him a custom cam for it.  He installed the cam, along with new adjustable pushrods, lifters, rocker arms, etc.  Got it all buttoned up and it wouldn't start.  Acted like it had zero compression.  He thought he had bent a valve, so he brought the heads to me and we checked everything out....it was all fine. 

He takes it apart and puts it back together at least 2-3 more times. 

He finally got it to start with the rocker covers off.  Pleased with it finally running, he goes to bolt the rocker covers on and notices one slightly teetering on the rocker arm. 

The new rocker arms hit the rocker covers in a way that when he bolted the covers down tight, it would open a valve about .020".  A quick adjustment with a die grinder and it was purring like a kitten. 

[cjshaker]

Which brings to mind if you looked for any witness marks under the valve covers? Perhaps a baffle or something? I've lost track of everything you've done, so maybe that was already covered, but I've had to remove the baffles out of my CJ covers in my Mach and the baffles out of the ones in the truck. It doesn't take much at all and you may not even be able to see it much.

[KMcCullah]

Brent and Doug beat me to this one. My dad is resurrecting my old 390. He had to peel the baffles out of some "Power by Ford" valve covers to clear Harland-Sharp rockers.

I drug out my head phones and spent 10min listening to your video, Ross.  Could it be possible that your shop missed when the crank was inspected/magnafluxed? 

[Heo]

checked the rods for straightnes?

[My427stang]

So a little bit of an update, but not much substance

Fired the truck cold after sitting a few weeks.  Made the noise pretty loudly, as it always does, the movie I originally posted was warm, so I pulled one plug at a time and didn't get any definitive answer, but #7 "may" have gotten a little quieter when it wasn't firing.  It certainly was the one I went back to a second time but it didn't go away completely like I had hoped.

Took it for a 10 mile drive and as it warmed up, it got significantly quieter, but not gone.  At this point, by deduction, not proof, I almost have to blame something with a single piston.  I'll get the 396 together, swap it out and dig in the 445 again, got some plans to make this a little 445 a little more bad ass, despite it being already too fast for the 4x4 steering, 4 wheel brakes and big old tires already 

The pistons in the 445 are forged 2618 Probes, but spot-on for clearances, so I doubt its a material issue.  I am hoping it's something behind a ring that i didn't see or   Who knows, but I will likely replace with pistons with 4302 Diamonds or Racetechs with a metric ring pack. 

We'll see though, time to get the little 396 together after I finish a run to the Pentagon.  That one should be fun, Streetmaster with all mods, iron heads with CJ valves and some port work, Diamonds with metric rings, zero deck, 6.54 rods prepped nice, 3.78 crank, true 10:1 compression, 280/284  230/236 @ .050 110 LSA on 106.  Might even run a 600 Holley on it because I have one.  Just a clean little 396 to get my heart pure again after this 445 LOL

[turbohunter]

Hell I'm just glad you have a new and bitchin sig picture.
Funny you're gonna tear it down. I've had a niggly little problem that I'm going to rip mine out again for. Might even lose the dreaded Performer.
Hope you find yours.
Hmm cooler louder, warmer quieter. A hundred things.
Good luck

[My427stang]

LOL, no kidding huh?  This truck would have EFI, a/c, power windows, and at least front disks by now, but I keep buying gasket sets!

BTW, here is a movie.  Nobody really heard it last time, but had the wife help today.

Listen at 26 to 28 seconds, if you don't hear it, back up to 24 seconds and listen when I get moving.  To set the stage I am backing out of the garage and move forward at 25 seconds or so.

Then, at 50 seconds, I get into the noise, get out, and in again.  Sounds like a bent pushrod, broken rocker....sorta

At the end, ignore a little grind, mama rested her had on the transfer case lever when I accelerated

https://www.youtube.com/watch?v=gnSd_lMyFNM

[WConley]

Maybe the audio is lying to me, but I don't hear any bad engine juju in that video.  I hear a sound like wind blowing through trees (or a whoosh like am radio static) at those points in the video you indicate.

If that's the real sound, it could be your clutch throwout bearing.  That might explain why it lessens when the driveline warms up...

[Joe-JDC]

I hope you find it.  I imagine it'll be a relief to know, regardless of what it is or how serious it is.

Thanks Paulie, honestly I couldn't care less if it was serious. LOL  In fact, I couldn't imagine a part in the engine I wouldn't happily replace and hang the broken one on the wall or happily spiral into the trash.. Now it's my Moby Dick. 

I forgot what your rank is, but it'd be cool to call you Captain Ahab.   

Let's not demote him!  He was up for O-5 last I heard, and that is worth at least two Captains!   On the noise, I had a CJ from the factory that had rod inserts that looked like they were beaten in with a ballpeen hammer.  Warrantied at less than 3000 miles, and the reason for the warranty was a noise off idle and with no load that only I seemed to be able to hear at the time.  The service manager did think he heard something, so they took a look.  Long story short was I got a rebuild and the car was super quick afterwards and no noise.   Joe-JDC

[plovett]

Thanks Paulie, honestly I couldn't care less if it was serious. LOL  In fact, I couldn't imagine a part in the engine I wouldn't happily replace and hang the broken one on the wall or happily spiral into the trash.. Now it's my Moby Dick. 

I forgot what your rank is, but it'd be cool to call you Captain Ahab.   

Let's not demote him!  He was up for O-5 last I heard, and that is worth at least two Captains!   On the noise, I had a CJ from the factory that had rod inserts that looked like they were beaten in with a ballpeen hammer.  Warrantied at less than 3000 miles, and the reason for the warranty was a noise off idle and with no load that only I seemed to be able to hear at the time.  The service manager did think he heard something, so they took a look.  Long story short was I got a rebuild and the car was super quick afterwards and no noise.   Joe-JDC

Lieutenant Colonel Ahab just doesn't have the same ring to it, Joe.    Ross will always be Captain Ahab to me, no matter his real rank.