[pastry_chef]

I can say one thing, IF this sound is something internal then a word "incompetence" comes to mind.. It was torn down and inspected and then you were forced to dyno it yet again "to make sure it didn't still knock".

[DOC]

I know you have used the screw driver method to listen to the engine and noise is from dist area.but have you used an actual mechanic stethoscope? If not, Place place along the block on the sides of each cylinder, , Each head bolt, , Each oil pan bolt,, on top of each rocker stud, Starter bolt, rear main part of oil pan with engine running, Oil galley plug next to dist, I can tell a definite difference between how I can hear something between a screwdriver and a mechanic stethoscope. I use the one from Harbor freight and it works much much better than a screw driver.

Hurts to say this, since the noise is internal and not valve train, Even if you find the noise, it will have to come back out....

Wishing you the best.

[chiphead]

Originally Posted by adynes

Is it possible it's an intake lifter refusing to pump up or with excessive leakage, making the noise and causing the rough idle? The noise honestly sounds "healthier" than a lifter in the videos, but videos and phone/laptop speakers don't always sounds the same as in person. Sounds more like piston noise to me from the videos...

Yeah, the more I think about it, based on the discussion, the history and the youtube videos, I'm thinking piston slap or a wrist pin issue. That would be impossible to diagnose in the car, would make a consistent, deep noise, and survive dyno runs and in-car time without having an obvious failure by now. I've asked detailed questions about the pistons and the clearances and never got a straight answer.

Whoever looks at this thing is going to scratch their head until they check the skirt to wall clearance and pin clearance on the back 4 cylinders. The sad thing is, if it's piston slap, it's likely safe to run it. It'll just make noise and wear the rings a little faster than a motor with tighter piston clearances.

[TedRamAirII]

I would think, disabling a spark to each cylinder and NO change, would rule out a Wrist Pin. But I think its a Wrist Pin.

[Va68goat]

scott70,
The only time this motor has been completely torn apart is after it failed on the dyno in Arizona and most recently when Paul said he replaced the bearings, piston rings, polished the crank and did a light honing. None of my buddies that have worked on the motor have taken a look at the lower end of this motor. I'm pretty sure this motor will have to come out and torn apart. There is not even a slight chance of me washing my hands of anyone....not a this stage! I'm pretty sure if my buddies that have worked on the motor tore this motor apart, I'm confident they would find something. It's not their problem though and I've already wore my buddies out with the amount of time they spent on this motor. I'm just as confident that if Jeff and Paul have their guy break this motor down, he too would find the issue.

adynes,
Paul sent me new lifters last year and I sent him the ones that were in the motor. When he received the lifters and inspected them, he said there was absolutely nothing wrong with them.

pastry_chef,
I think Paul has had a great reputation of building motors. He says he's built hundreds of them without any issues. On the other hand, people make mistakes. I think one problem is that we've been asked to spend 165 hours of diagnosing things that we could have done wrong installing the motor instead of accepting the fact that something could have been done wrong on the build. With a catastrophic failure on the dyno, something was missed. I still believe the failure of the distributor bushing could be the result of a greater issue. We have done everything that was asked and the knocking noise is still the same. This has to come to a conclusion very soon.

DOC,
We've used a mechanics stethoscope multiple times. We get a signature at the distributor and lower end of the motor. We discovered that over a year ago but I still get questions about how old the fuel is. (The fuel is only 3-4 months old)

[Va68goat]

These pictures were taken last year just prior to getting the heads inspected.

Sent from my SM-G955U using Tapatalk

[Va68goat]

Maybe this will mean something to someone when compared to the other pics.

Sent from my SM-G955U using Tapatalk

[Formulas]

One thing is sure until the world knows exactly why it runs like it runs you cannot place blame on anybody or anything as you simply don't know

Its cheaper and more gratifying to build your own taking your time if you don't know how at first after all its 50's technology

[Va68goat]

Formulas,
I agree 100%. Honestly, I was hoping it was something that wasn't done correctly on our end but after 165 hours of diagnosing, thats getting less likely. I don't care to place blame, I just want the this motor right.

[Sun Tuned]

I'll say this, you running it on diesel fuel?

Dang I tore apart a 652,000 mile 6.0 Ford that was cleaner than that.

I'm sure it's an illusion but that first pic left cylinder st about the 2 o'clock position on outer edge of piston... what is that that looks like a small fracture? It's reflected in the cylinder wall too.

As said earlier, miss still there.

[Va68goat]

Sun Tuned,
Hahaha. No diesel. (93 Octane pump gas). This picture was taken when the motor had around 150 miles drive time and a bunch of idle time while we were diagnosing the knocking noise.

[Sun Tuned]

Then what I'm about to say is gonna hurt some feelings...

I'll be glad to do my own carb and distributor work right here when I need it , thank you very much.

Wow, I'm serious my 6.0 diesel was lots cleaner than that after 652,000 miles. I do realize coolant spilled on everything when heads came off of yours making stuff look funny.

I know why it was missing now.

I wish you the best and all the speed in getting it up quietly up and running strong.

[Sun Tuned]

I see lots of oil. Some wierd shiny marks on a couple piston tops that probably are picture playing tricks with your eyes kinda stuff. I'm sure that what that is cause I'm sure Paul and Jeff already looked at this.

Damn engine looks like u been running Kerosene Lamp oil in it for only having 150 miles on it. Loose valve guide clearance or some crappy valve stem seals.

I got nothing else to add so I'm just gonna shut up and watch from sidelines.

[ponjohn]

Originally Posted by Sun Tuned

I see lots of oil. Some wierd shiny marks on a couple piston tops that probably are picture playing tricks with your eyes kinda stuff. I'm sure that what that is cause I'm sure Paul and Jeff already looked at this.

Damn engine looks like u been running Kerosene Lamp oil in it for only having 150 miles on it. Loose valve guide clearance or some crappy valve stem seals.

I got nothing else to add so I'm just gonna shut up and watch from sidelines.

Detonation?

[Gator67]

Originally Posted by ponjohn

Detonation?

Might some of it be due to all the troubleshooting? Repeatedly running the engine for short periods of time without ever letting it fully warm up. I would think you’d have build-up that compounds, eventually snowballing to other issues.

[GTO JONES]

Long shot throwing it out there, have you tried spraying a liquid like WD-40 or starting fluid something like that around the intake gasket while it is running, if there is a vacuum leak the idle will change /

[NeighborsComplaint]

I agree. Looks like you had some detonation going on there. Not the cause of the knocking though.

[Va68goat]

GTO JONES,
Thats what we did last weekend and we found the vacuum leak. We replaced the intake gaskets and the motor is idling much better now.

I did have the heads inspected last year and they said all checked out good.

[Holeshot71]

Is there any chance you have any better pics of the exhaust flanges? It's hard to see but looks like the center ports were sealed up well but #2 and #8 not so much.

[redhawk44]

I see one of the intake valves is especially clean. A lot cleaner then the rest, while it doesn't explain the nock is that cylinder even firing?