[68 461 Bird]

Originally Posted by grivera

This isn’t fair as it makes it sound like Paul hasn’t done anything - he has spent many hours on phone with Joe directing every move he made to diagnose this issue. It’s my understanding every part replaced or checked was co-signed by Paul.

I think it's plenty fair, Joe has offered Paul a free trip to his house to look at the engine and has refused. Paul has charged Joe a ot of money and he doesn't have what he paid Paul for, a great running engine without a knocking noise!. 120 hours of diagnostic time, $1,900 in extra parts. 2 years of trying to figure out a knock, tell me where I am wrong.

[68 461 Bird]

Originally Posted by Va68goat

Jeff sent me a text and said he located someone that can look at the motor.

Good news!

[grivera]

Originally Posted by 68 461 Bird

I think it's plenty fair, Joe has offered Paul a free trip to his house to look at the engine and has refused. Paul has charged Joe a ot of money and he doesn't have what he paid Paul for, a great running engine without a knocking noise!. 120 hours of diagnostic time, $1,900 in extra parts. 2 years of trying to figure out a knock, tell me where I am wrong.

This is the statement I was addressing:

“Wow $4,500 extra for a knocking engine and Paul hasn't done anything to right this situation except blame it on bad gas?”

[hurryinhoosier62]

Originally Posted by TedRamAirII

Maybe you should talk to some Dealer Techs. Lot of Dodge roller issues. https://hemimdslifters.com/

Ted, in my experience I've never seen it, but I have been retired for several years. Refer back to the beginning of my post..."It's possible". Did you bother to read the attachment.....FROZEN LIFTER ROLLERS, NOT bad cam cores.

[67gtospud]

Reading through this thread and I don’t see mention of the flexplate at all. Is it new or used? What was used on the dyno? I know the op said he disconnected the converter to eliminate that, but was the flexplate checked? I’ve diagnosed multiple cracked flexplates over the years that have sounded like a spark knock at idle and faded as rpm raised with no load on the engine.

[hurryinhoosier62]

Originally Posted by "QUICK-SILVER"

In the dyno video it appears the engine had short head pipes ONLY on the exhaust manifolds. Engine would have been way too loud to hear the TAP TAP TAP.
https://www.youtube.com/watch?v=PiSatCtuA3U

Normal engine noise drowns out the TAP TAP TAP now (with closed exhaust) at engine speeds above idle.

If Jeff and Joe are still talking...Joe needs to get Jeff to ask Paul about rod little end to counter weight clearance. Joe got a sarcastic "LOL never heard of it" when he asked Paul.

Clay

Piston skirt would be in interference before the pin end of the rod would be. That scenario is definitely NOT a "tapping" situation.....

[grivera]

Joe replaced the flexplate- with one he sent Paul and had balanced.

[aceaceca]

How about a ballooning converter pushing the crank forward. Seen one and the amazing damage it caused. Jut a thought. Especially if the engine does not knock with the converter off or pushed back.

[hurryinhoosier62]

Joe, where in VA are you? I'm going to be in far western SC in a couple of weeks. You wouldn't be that far out of my way.

[Va68goat]

aceaceca,
If the cam moved and Paul had this motor apart like he said he did, I'm sure he would have checked that.

[grivera]

Originally Posted by aceaceca

How about a ballooning converter pushing the crank forward. Seen one and the amazing damage it caused. Jut a thought. Especially if the engine does not knock with the converter off or pushed back.

Originally Posted by Va68goat

aceaceca,
If the cam moved and Paul had this motor apart like he said he did, I'm sure he would have checked that.

crankshaft - but yes, Paul would have checked the thrust bearing

[Va68goat]

hurryinhoosier62,
I sent you a PM

[chiphead]

So what are the compression test numbers, with all 8 plugs out and throttle at WOT? Gotta test with a charged battery, as a weak battery will produce low numbers.

Low compression could indicate several things, poorly set valves among them. Bottom end issues such as piston slap, rod small end contact, crank endplay, distributor issues, oil pump problems, etc don't typically cause low compression. The engine should still run strong and even.

So, what are compression readings?

[HWYSTR455]

Originally Posted by grivera

I think Mike R (HWYSTR455) tried a different coil during a different testing session- Mike ? ....

I did have a known good coil with me when I went over, but didn't try it. When I made initial adjustments, and bypassed the ignition 12v wire, I felt the knock had somewhat subsided, but admit the idle was at 1000 rpm, and was more unnoticeable.

In the latest vids, you can see the vacuum gauge swinging while it's missing. I believe that is a key factor, the miss coincides with the knock.

I still don't understand why someone would bother checking total timing and not initial, and the one time it cranked it cranked slow. I still say in that vid the initial timing is too high, but don't believe that's what's making it knock. There is some type of ignition or valve/valvetrain issue to cause a consistent miss like that. Some type of abnormal combustion, which could certainly cause an audible knock like what's being experienced.

EDIT: I'm glad to see a number of tests were done that eliminated several questions/possible causes, that narrows it down more.

.

[HWYSTR455]

Originally Posted by "QUICK-SILVER"

Of course not. I think that posters rant and the follow up statement is the only way he knows to say 'i don't know'.

I've still got the same thoughts on the TAP TAP TAP that I had from the get-go.

Just wish some one would have been there to look one of the times that the pan was off. It's something that needs checked or looked at with all makes of china rods. Got to have more clearance there than side clearance on big ends.
Or you get a TAP TAP TAP, like the OP's, that is loud at low rpm's and quietens when you rev it up. Time and the gyroscope effect (object in motion) keeps it from knocking at higher rpm's.



Clay

Wow Clay. Couple things there, what stroke crank is that, and what brand crank & rods? One thing I see is there is zero radius on that crank throw, but that does still look like a ton of side clearance to me. I would think the crank wasn't finished right on first guess, when it comes to the counterweight.

.

["QUICK-SILVER"]

Originally Posted by HWYSTR455

Wow Clay. Couple things there, what stroke crank is that, and what brand crank & rods? One thing I see is there is zero radius on that crank throw, but that does still look like a ton of side clearance to me. I would think the crank wasn't finished right on first guess, when it comes to the counterweight..

Think that one was a stock crank 455 with PRW rods. Here's another that had the same problem but with RPM rods.




Rods in both engines had the wonky machine work (beam centering) on the big ends that make them "look like" they've been installed backwards. Just like the rods in Joe's engine. Wide radius side is all over the place and moves the little end closer to the counter weights. Rod #7 below appears to have the wide side towards the middle. That rear counter weight appears to have a silver streak on the beveled edge close to where contact would happen



Usually can mix match/swap holes to get away from the counter weights. Or grind a little off the little end to get clearance. Same with all makes of China rods. Some get lucky....some don't

Clay

[hurryinhoosier62]

This engine was screwed up from the get go. That SHOULD have been heard just rotating the engine through during assembly.

["QUICK-SILVER"]

Originally Posted by hurryinhoosier62

This engine was screwed up from the get go. That SHOULD have been heard just rotating the engine through during assembly.

My thoughts on that,

.001" clearance during assembly wouldn't be there with the engine running on the power stroke.
OP's engine knocks at slow idle but doesn't at the same speed spinning it with the starter.

Clay

[grivera]

Originally Posted by Va68goat

Mike Davis,
Jeff sent me a text and said he located someone that can look at the motor.

Did he say who or when?

[Formulajones]

Originally Posted by HWYSTR455

I still don't understand why someone would bother checking total timing and not initial,
.

Since this thread has swung all over the place I can't determine who that refers to. But in a nutshell, when an engine is run on the dyno, total timing is really the only thing you're concerned with, to find the spot where the engine makes best power. The rest of it is up to the end user to determine what the car likes best because there are way too many variables that will change the requirements, none of which can be found on an engine dyno.

You'll have to change initial timing to suit the car by modifying the breaker plate, the rate of the curve will likely need to be slowed down a bit, and the vacuum advance adds more to the equation after everything else is nailed down. None of that has been posted that I can find. This stuff has to be done once in the car. If it's still an MSD distributor this stuff is very simple to do once put in service, and they even provide a chart to follow.

There really isn't enough information provided here on the users end that I can find that can determine a cause for anything one way or another. I haven't seen any timing numbers posted, I have seen compression test numbers posted or how the test was done. Just saying they are low doesn't tell anyone anything. Is there a post here somewhere with this information that I am missing??

And Paul is well aware of the rod issues when it comes to cranks with BBC rod journals and aftermarket rods in these Pontiacs. It's been a problem in the aftermarket for quite some time. That area has been addressed so you guys are going after a dead end there.