#1361  
Old 09-20-2019, 06:45 PM
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Originally Posted by DOC View Post
Any update?
Does no update mean he's out running the wheels off it?

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  #1362  
Old 09-20-2019, 09:40 PM
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Refer to post 1356

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  #1363  
Old 09-21-2019, 10:45 AM
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Originally Posted by ponchjoe View Post
Refer to post 1356
Joe's wife cooked?????

  #1364  
Old 09-21-2019, 10:44 PM
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Originally Posted by redhawk44 View Post
Does no update mean he's out running the wheels off it?
Yes or at least he was earlier today. I’ll let him tell the story but the issue should have been resolved upon return the first time. Once I found out what it was I wondered how a machinist missed it

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  #1365  
Old 09-22-2019, 05:14 AM
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I want my prize ... I think I was right 10,000 posts ago.

  #1366  
Old 09-22-2019, 06:34 AM
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Well, I'm pretty sure that a lot of guys are finally glad to see this thread come to a close..myself included. Paul flew out here last Wednesday and just left today. Paul disassembled the engine in my garage and checked the pistons while they were in each cylinder. When he got to piston #5, he noticed there was a lot of play in the piston while it was positioned at the top of the cylinder. Paul pulled all the pistons out and when he inspected piston #5, he noticed that the piston skirt had collapsed. When he measured it, he said the skirt collapsed 40 / 1,000. Paul inspected the cylinder wall on #5 and did not notice any damage. He took measurements and was able to verify everything was good with the cylinder walls. Remember, when the engine failed on the dyno, rod #5 was one of two rods that had to be replaced.

Paul called Jeff and they ordered another piston. We got the piston the next day and Paul reassembled the engine. We installed the motor and started it up and the knocking noise was gone. I, along with all of my experienced friends that worked on this engine can say with 100% certainty that the knocking noise was exactly the same from when I first got the engine delivered, to when I received it this last time. The bad distributor bushing may have been another problem but the source of the knocking noise was a collapsed piston skirt. This problem existed from the very first day that this engine was started.

Here is a video of the engine idling once we got the carburetor dialed in.
- https://www.youtube.com/watch?v=dfoiPqVZk-Q

Spending the last few days with Paul, I can say this. I think he's a good guy. He stayed at my house, met my wife and kids. (No, Paul was not subjected to my wifes cooking--hahaha). I think this whole engine build just snow balled into something that caused both of us to lose our cool at times. Mistakes were made on this build and thats obvious. Though I think Paul is a good guy and a good engine builder, business is business. I don't think any member of this forum or even Paul and Jeff themselves would accept the last bill that I received of $2,575. So on the way to the airport today, I told Paul that I think it's only fair that Koerner Racing Engines give me a complete refund of the $2,575. I'm willing to overlook the $1,900 I had in replacing parts, tools to diagnose the problem and fluids. Over 180 hours was spent diagnosing this engine and I lost almost 2 years of enjoying this car. To refund my $2,575 is only fair. I'm hoping that Jeff agrees to that because if he doesn't, I'm going to be forced to go another route where the $1,900 won't be forgiven along with other expenses. I won't be mentioning too much of that aspect of this issue but if Jeff does the right thing and returns my $2,575, I will mention that on the forum because that will show that they did the right thing. As I was told numerous times, the best way to judge a builder is how they handle a problem.

So while Jeff makes his decision, I will be enjoying this car. This car has been through hell for the last 2 years, I'm going to spend the day cleaning it.
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Last edited by Va68goat; 09-22-2019 at 07:00 AM.
  #1367  
Old 09-22-2019, 06:36 AM
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  #1368  
Old 09-22-2019, 08:16 AM
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Quote:
Originally Posted by abefromen View Post
Strangely similar to the noise my old .060 over 389 used to make.

https://www.youtube.com/watch?v=iAGp6IdSTl4

In my case it turned out to be a piston issue.

I win! I win!

  #1369  
Old 09-22-2019, 08:20 AM
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In speaking with guys that worked on and diagnosed my engine, it's believed that the piston skirt collapsed while on the original / failed dyno run. when #5 spun the rod bearing and the piston hit the head. There was a small mark on the cylinder head. This was the conclusion of two guys that worked on the engine that not only do this is a hobby, one of them is a machinist that currently works on very high end cars. The other had his own shop for many years and is a forum member.

Unanimously, the guys that diagnosed my engine said that this should have been caught when the motor was sent back to Arizona, if this engine was really completely disassembled the obvious scuffing of the piston skirts should have been noticed. If the scuffing of the piston skirts had been observed while it was disassembled, it should have been measured. They said if the engine was really apart and the piston skirts were mic'd, it would have been easily discovered as it was in my garage. I'm only adding this information because the last time I withheld information on this thread, it came back to haunt me.


Last edited by Va68goat; 09-22-2019 at 08:36 AM.
  #1370  
Old 09-22-2019, 08:46 AM
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Quote:
Originally Posted by gtofreek View Post
I'll say it again, that noise is not piston slap. The pistons are 2618 material and they require a minimum of .0045" clearance and when I measured them they are at .0047" after honing it. It's not piston slap. Doesn't even sound like piston slap. Anyone that's heard piston slap would know that.
Looks like someone made an assumption here.

  #1371  
Old 09-22-2019, 08:48 AM
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It’s finally over on page “69”! Would have been nice to end it on 68! Lol. That’s too cool man. Enjoy that car. Hope the rest of it goes easy

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  #1372  
Old 09-22-2019, 09:21 AM
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What does a collapsed piston skirt mean?

It's worn, it suffered trauma?

  #1373  
Old 09-22-2019, 09:50 AM
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Are the rods full floating or pressed?

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  #1374  
Old 09-22-2019, 09:58 AM
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First, I am happy the problem with your engine has been diagnosed, verified, repaired, re-installed, run and verified again. That ends the mechanical drama of this very long thread. Financially, That's between you and the parties involved and I have no comment about that. Technical detail question. In your explanation of the problem once found, you stated that the #5 piston skirt was collapsed .040". That is nearly 9 times the proper piston to wall clearance!! I am assuming you meant to say the skirt had collapsed .004" more than specs. which would still produce a light knocking noise.
A few other observations. I have worked with automotive engines for over 45 years and have machined hundreds of blocks and heads. Mistakes can and do happen no matter how careful we are and they always are upsetting to the shop and the customer. From my experience working on vintage, high performance engines, this is the typical breakdown of what happens when there is a serious problem. At least 50% of the time, the customer is blamed for the issue and the shop assumes no responsibility and it ends there. 25% of the time a little help may be offered over the phone with the tone that it is still the customers fault and they did something to cause this. I sensed nothing of the sort with your engine or the shop and I commend you and Paul and all those involved in keeping a level head for the most part and staying on task to solve this in a public forum. The engine shop I have worked with for over 30 years has a sterling reputation but has had a few failures over the years. Probably 3-4 engines have come apart on the dyno, some engine noises like yours, a few oil burners. In every case that I know of, the problems have been diagnosed and solved. It can be time consuming and tedious as you have found out, but ultimately, the problems have been solved. The second an engine noise was verified, I am sure Paul and his shop knew any profit from all his hard work and effort would be gone. That's the unfortunate nature of this business. In my current shop situation, I have a special insurance policy to help recover financially if a mistake is made. The premium is pretty high and it has a $1000.00 deductible. I have it because we ALL make mistakes.
The fact that Paul made a trip across the country, diagnosed and repaired the engine says allot about him and the shop.
In closing, allot of people on this thread learned something of value from this monumental effort. I know I did. If 100 people had a place to send $20.00 as an "educational fee", your extra expenses would be mostly covered. I am in. Anyone else?

  #1375  
Old 09-22-2019, 10:05 AM
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Quote:
Originally Posted by Va68goat View Post
They said if the engine was really apart and the piston skirts were mic'd, it would have been easily discovered as it was in my garage
Agree.
I could not remember the parts replaced on the trip back, looks like the piston rings were.

Quote:
Originally Posted by gtofreek View Post
Also looked like the distributor jacking the timing up may have been causing some detonation as some of the top rings showed signs of the Moly coating starting to flake off. Just buying top rings from Total Seal was more money than just buying a whole set, so we bought a whole set.

  #1376  
Old 09-22-2019, 10:10 AM
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74SDformula,
Yeah. I don't even know what to say.

shoebox1.1,
Thanks. I certainly learned a lot about engines. I'm looking forward to some drive time!

ponjohn,
There was "trauma" to the piston skirt. I sent the bad piston to a respected machinist who my buddy has been using for close to 20 years. He along with a few other guys that know what they're doing state that the piston likely touched the head during the original dyno failure when the number 5 rod spun a bearing. The machinist analyzed the piston and said the piston had been "smoothed" out in attempt to mask the damage when it hit the head. I'm not trying to throw Paul under the bus here, I'm just repeating what the machinist came up with after analyzing the piston.

AG,
I have no idea what that means but maybe someone can chime in. (grivera)

  #1377  
Old 09-22-2019, 10:11 AM
TedRamAirII TedRamAirII is offline
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Hard to imagine that piston issue being missed, twice. Once after the Dyno mishap, then again when returned and the Distributor Bushing issue repaired. 2 Dyno runs after repairs and no noises heard. Happy its all together and ready to peel your eyelids over your forehead!

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  #1378  
Old 09-22-2019, 10:13 AM
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pastry_chef,
I was told and charged for new bearings and piston rings


Last edited by Va68goat; 09-22-2019 at 10:35 AM.
  #1379  
Old 09-22-2019, 10:16 AM
mgarblik mgarblik is offline
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Quote:
Originally Posted by ponjohn View Post
What does a collapsed piston skirt mean?

It's worn, it suffered trauma?
A collapsed piston skirt is a situation where the lower part of the piston, (skirt) crushes in toward itself in operation. From here, it gets rather complicated. The tendency for a skirt to collapse depends on a huge number of factors. Here are a few: 1. piston material 2. piston head design 3. piston skirt design 4. piston pin box design and support 5. cam grind on the skirt 6. piston skirt strut support and design. 7. oil drainback design in the oil ring groove 8. piston to wall clearance 9. amount of piston skirt that comes out the bottom of bore at BDC 10. piston to rod ratio 11. dwell time at TDC 12. detonation 13. mechanical interference 14. Dozens of other factors.

So it's a complicated series of compromises that go into piston design, machining clearances , and material choice, and application that determine the final outcome.

  #1380  
Old 09-22-2019, 10:22 AM
mgarblik mgarblik is offline
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First, I am happy the problem with your engine has been diagnosed, verified, repaired, re-installed, run and verified again. That ends the mechanical drama of this very long thread. Financially, That's between you and the parties involved and I have no comment about that. Technical detail question. In your explanation of the problem once found, you stated that the #5 piston skirt was collapsed .040". That is nearly 9 times the proper piston to wall clearance!! I am assuming you meant to say the skirt had collapsed .004" more than specs. which would still produce a light knocking noise.
A few other observations. I have worked with automotive engines for over 45 years and have machined hundreds of blocks and heads. Mistakes can and do happen no matter how careful we are and they always are upsetting to the shop and the customer. From my experience working on vintage, high performance engines, this is the typical breakdown of what happens when there is a serious problem. At least 50% of the time, the customer is blamed for the issue and the shop assumes no responsibility and it ends there. 25% of the time a little help may be offered over the phone with the tone that it is still the customers fault and they did something to cause this. I sensed nothing of the sort with your engine or the shop and I commend you and Paul and all those involved in keeping a level head for the most part and staying on task to solve this in a public forum. The engine shop I have worked with for over 30 years has a sterling reputation but has had a few failures over the years. Probably 3-4 engines have come apart on the dyno, some engine noises like yours, a few oil burners. In every case that I know of, the problems have been diagnosed and solved. It can be time consuming and tedious as you have found out, but ultimately, the problems have been solved. The second an engine noise was verified, I am sure Paul and his shop knew any profit from all his hard work and effort would be gone. That's the unfortunate nature of this business. In my current shop situation, I have a special insurance policy to help recover financially if a mistake is made. The premium is pretty high and it has a $1000.00 deductible. I have it because we ALL make mistakes.
The fact that Paul made a trip across the country, diagnosed and repaired the engine says allot about him and the shop.
In closing, allot of people on this thread learned something of value from this monumental effort. I know I did. If 100 people had a place to send $20.00 as an "educational fee", your extra expenses would be mostly covered. I am in. Anyone else?

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