[TedRamAirII]

Any Trans shop could replace that in 1 hour. I once was talking to a friend that owns a trans shop, as I was going in, he had a guy there pulling the trans back on a 1990 Camaro to replace the flex plate because of a starter issue. I think I was in there 30 minutes and as I was leaving, the car was being lowered on the lift.

[grivera]

I believe Joe will be doing some more testing this weekend. If he unbolts the converter from the flexplate pulls it back and the noise remains, will that rule-out the flexplate being the culprit?

[dataway]

Fingers crossed.

[Sirrotica]

Originally Posted by grivera

I believe Joe will be doing some more testing this weekend. If he unbolts the converter from the flexplate pulls it back and the noise remains, will that rule-out the flexplate being the culprit?

I would say yes, because there is no flex going on when the two aren't bolted together. If it doesn't go away and the flexplate is rotating by itself, the noise should change appreciably, I would think it should go away though.

["QUICK-SILVER"]

Next step should be a surgical clean oil and filter inspection. That's with a spotless clean white or clear drain pan.
I'd stick a flex head pocket magnet in the oil drain hole to see if any of the previous metalic paint look is present now and if it was ferrous or nonferrous.
Use the same magnet to check filter contents and oil in the pan.

If that oil is fresh and clean...It can go back in.

Joe was told that X amount of metal in the oil was normal for a new engine. This unknown X amount should've been gone after a few oil changes I would think.

With Paul's honing process and roller cam....I think this engine had way too much glitter look in the filter and oil pan pics.

IF metalic is still present and if the filter bypass is functional....This engine could be in worse shape than the original knocking noises.

The first converter un-bolt had no affect on the bottom end noise or the collapsed lifter type noise on top.

Hard to tell watching videos, but in the most recent top side vids, the knocking sounds more defined and louder.

IDK for sure but know what I think
Clay

[HWYSTR455]

Originally Posted by grivera

I believe Joe will be doing some more testing this weekend. If he unbolts the converter from the flexplate pulls it back and the noise remains, will that rule-out the flexplate being the culprit?

In most cases yes, unless it is actually a crack at the mounting surface of the flexplate where it meets the crank flange. It could also be contacting something protruding from the pan or block (but not very likely).

As for glitter, I would have to go back and look at the pics, honestly don't recall off the top of my head, but I do remember there were no red flags. Not sure if it was the pics, or if it was residual from the windage tray and valley pan, but I saw no reason for alarm.

Yeah, I recall the first converter pull back and results (I wasn't present), which is why I commented on the flexplate hub and possible crack there. Long shot, but can't honestly say if it was checked in depth enough to tell if it was a crack somewhere else, other than the common converter mount points. Should know soon enough though.

.

[dataway]

I can't believe you guys are discounting my in depth sound analysis that says this is a noise at 1/2 crankshaft speed

I'm going with a slightly bent oil pump drive shaft that intersects the crankshaft counter weight every other revolution. Just kidding.

Can't wait to find out what it is.

[gtofreek]

The metallic look in the oil I'm sure is just the moly lube I used on the cam gear and distributor gear. That stuff makes the oil look all glittery. Not a problem if that's all it is. I think if it had a bearing problem, it would have been evident by now.

[Va68goat]

Well...there isn't much to report. Looks like I'm going to take the GTO to a local shop to replace the flexplate. This is a shop that is recommended from a forum member. I'm hoping that this is the cause for the knocking noise. I'm not too confident that this is the issue or not but I'm hoping. I'll have the mechanic pull the converter back and run the car to see if the noise is still present. If this isn't the issue, it's going to have to go back to Arizona!

The good news is..is that Jeff Koerner has been working on a carburetor for me since June and it should be here this week so I can get that on the car at the same time as the flexplate gets switched out..

[grivera]

If it still makes the noise after they pull the converter back replacing the flexplate will likely be a waste of time/money. The reasoning being it won't have any tension on it from the converter.

[LeGoaT/As]

Va68goat, I sent you a PM.

Lynn

[aceaceca]

I am going to mention something I only heard of recently as a friends 70 Riviera destroyed its engine due to the problem. A "Ballooning Torque Convertor". Evidently fairly common problem back in the day. The Riviera had been cracking flex plates. Number 3 cylinder developed a knock due to rod bearing problems. The crank was ruined at the thrust bearing surface looked as if it had been machined down. All this trauma was due to extreme pressure being exerted by the torque convertor as it puffed up and forced the crank forward. Live and learn. My 65 GTO had a factory flex plate on it that looked like a spider web. I have no idea why it did not implode. Just another thing to consider.

[Va68goat]

LeGoaT/As,

Thanks for your message. I just responded back!


aceaceca,

I've done a visual inspection of the flexplate while it's on the car and I don't see any evidence of cracks. I'm hoping that none of what you described has occurred..hahaha. This motor has less than 200 miles on it. It hasn't been right since the day I started it. I'm hoping to get things looked at this weekend. grivera, has a good point...there's no reason to pay to have the flexplate replaced if we pull the torque converter back and it's still knocking....you guys agree with that?

[HWYSTR455]

Originally Posted by Va68goat

LeGoaT/As,

grivera, has a good point...there's no reason to pay to have the flexplate replaced if we pull the torque converter back and it's still knocking....you guys agree with that?

Not sure I agree, it might only knock with a load on it from the converter. Also, if there's something the flexplate is striking on revolution, with the flexplate off, could see witness marks.

.

[grivera]

Originally Posted by HWYSTR455

Not sure I agree, it might only knock with a load on it from the converter. Also, if there's something the flexplate is striking on revolution, with the flexplate off, could see witness marks.

.

That's my point - if it only knocks with the load on it from the converter he will know when converter is pulled back. At that point we can assume it's either the flexplate or the converter. If the sound continues after pulling the converter back I don't see how it could be the the flexplate because the sound is very random in nature.

[dataway]

Any news yet?

[Va68goat]

dataway,

No news yet. I'm in the middle of processing my retirement so I haven't had much time to work on the car. I'm also waiting for the carburetor that Jeff Koerner is building for me so I can replace the flexplate and switch out the carb at the same time. I've been waiting for the carburetor since June but it was supposed to be shipped yesterday...I haven't heard anything yet about it. The carb that he's building is supposed to be the same carb that Paul dyno'd the motor with when it made 550 hp. So I don't have to bother my friends too much, I figured we would wait to switch out the flexplate whenever I get the carb that Jeff built. I will update this post soon!

[wovenweb]

Bump/to the top

[Va68goat]

Well...the thought of having my car ready for my retirement date has come and gone. The car is still knocking. We still need the switch out the flexlplate to see if that will fix the knocking noise. Everyone seems to think that may not be the issue. I imagine there is no other option other than to send the motor back to Arizona after we switch out the flex plate. Every test, every switched out part was under Pauls directions and approval and the problems still exists. I would hate to have to pull the motor again but Paul and Jeff have been great and we have stayed in touch. I'm actual in Vegas now on my retirement vacation. That motor is my priority when I get back home. The motor has around 200 miles on it. I plan on driving it a lot when I'm retired. Hopefully more to update soon!

[tempest1964]

Keep at it. Perserverance will prevail. Good luck.