Broke connecting rod?

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Kevin Johnson
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Re: Broke connecting rod?

Post by Kevin Johnson » Wed Sep 19, 2018 10:42 am

lance flake wrote:
Wed Sep 19, 2018 10:39 am
Kevin Johnson wrote:
Wed Sep 19, 2018 10:31 am
lance flake wrote:
Tue Sep 18, 2018 9:12 pm
image.jpeg

Take high resolution pictures of the area of the fracture where the bluing is seen on the upper beam section. Heat is generated when a fracture flexes.
Will do i think the blueing is from the bottom piece swinging around and hitting the upper piece after failure
No.

lance flake
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Re: Broke connecting rod?

Post by lance flake » Wed Sep 19, 2018 10:43 am

Biteme wrote:
Tue Sep 18, 2018 10:26 pm
1st thing I’d do is check the balance of the torque converter if it’s the same one hes used all along.
The converter was gone through before this failure

lance flake
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Re: Broke connecting rod?

Post by lance flake » Wed Sep 19, 2018 10:45 am

Kevin Johnson wrote:
Wed Sep 19, 2018 10:42 am
lance flake wrote:
Wed Sep 19, 2018 10:39 am
Kevin Johnson wrote:
Wed Sep 19, 2018 10:31 am


Take high resolution pictures of the area of the fracture where the bluing is seen on the upper beam section. Heat is generated when a fracture flexes.
Will do i think the blueing is from the bottom piece swinging around and hitting the upper piece after failure
No.

I will get a better pic of that this evening.

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Re: Broke connecting rod?

Post by lance flake » Wed Sep 19, 2018 10:48 am

If there is somewhere i can send pieces to for real lab analysis i would be glad to. I really want to know what caused this failure. I want to make sure i did nothing wrong and i want to find his problem so we can fix it as best possible

Kevin Johnson
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Re: Broke connecting rod?

Post by Kevin Johnson » Wed Sep 19, 2018 10:49 am

lance flake wrote:
Wed Sep 19, 2018 10:48 am
If there is somewhere i can send pieces to for real lab analysis i would be glad to. I really want to know what caused this failure. I want to make sure i did nothing wrong and i want to find his problem so we can fix it as best possible
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fdicrasto
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Re: Broke connecting rod?

Post by fdicrasto » Wed Sep 19, 2018 11:56 am

Just keep in mind, should anyone ask, these Callies compstar rods are manufactured OFFSHORE. Callies then finishes and checks them thoroughly and off they go. I personally feel 99% of these rods will be fine up to a certain point based on hp, rpm range and # of cycles but guess what? sh-t happens.

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Re: Broke connecting rod?

Post by fdicrasto » Wed Sep 19, 2018 12:02 pm

fdicrasto wrote:
Wed Sep 19, 2018 11:56 am
Just keep in mind, should anyone ask, these Callies compstar rods are manufactured OFFSHORE. Callies then finishes and checks them thoroughly and off they go. I personally feel 99% of these rods will be fine up to a certain point based on hp, rpm range and # of cycles but guess what? sh-t happens.
My mistake in that I see that these were Ultra rods. These are fully made in the USA . Sorry about that.

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Re: Broke connecting rod?

Post by lance flake » Wed Sep 19, 2018 5:25 pm

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lance flake
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Re: Broke connecting rod?

Post by lance flake » Wed Sep 19, 2018 5:26 pm

Kevin Johnson wrote:
Wed Sep 19, 2018 10:42 am
lance flake wrote:
Wed Sep 19, 2018 10:39 am
Kevin Johnson wrote:
Wed Sep 19, 2018 10:31 am


Take high resolution pictures of the area of the fracture where the bluing is seen on the upper beam section. Heat is generated when a fracture flexes.
Will do i think the blueing is from the bottom piece swinging around and hitting the upper piece after failure
No.
See if those above answer your question. I don't see any blueing at the break

Kevin Johnson
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Re: Broke connecting rod?

Post by Kevin Johnson » Wed Sep 19, 2018 5:49 pm

It is possible that the bluing seen in the collection photograph is an optical illusion ?? But you appear to see it as well.

https://www.efatigue.com/training/Chapter_3.pdf

When you bend a paperclip wire back and forth it generates heat in the area of plastic deformation. Eventually failure ensues. If the rod was accidentally dropped or struck and a small unnoticed nick was created that would be a stress raiser. There could also have been an invisible internal flaw in that area.

Send the pieces to be looked at by a trained metallurgical engineer.

prairiehotrodder
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Re: Broke connecting rod?

Post by prairiehotrodder » Wed Sep 19, 2018 5:58 pm

This may sound way out in left field, what would happen if there was nothing in that cylinder ? Like no fuel at all to compress ? And that rod was just kind of free-wheeling ? Is it possible it could pull apart from the Rpm but no cushion to hit against ?


With no cushion, the piston wants to just keep going up, but the crank is trying to pull it down, at 7500 rpm thats alot of force.

Maybe it slightly bent a valve first, then lost compression, then pulled apart the rod ?

Brian
Last edited by prairiehotrodder on Wed Sep 19, 2018 6:07 pm, edited 2 times in total.
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exhaustgases
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Re: Broke connecting rod?

Post by exhaustgases » Wed Sep 19, 2018 6:00 pm

Take the pieces to a shop that can check the hardness, the web area looks like its pretty hard. If its a shop that does aircraft parts manufacture they may be able to check the composition of the material as well. With the correct tools it is a very fast check for both. And the right place may do it for free.

1972ho
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Re: Broke connecting rod?

Post by 1972ho » Wed Sep 19, 2018 6:17 pm

I think it just broke,I mean how many rods are they forging every day I mean they all can’t come out perfect it just fatigued after a few cycles and broke.Sometimes stuff just breaks.

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Re: Broke connecting rod?

Post by kosky racing » Wed Sep 19, 2018 7:03 pm

What parts were carried over on the three engines that broke? -Ignition- fuel- manifold?

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Re: Broke connecting rod?

Post by Newold1 » Wed Sep 19, 2018 7:37 pm

I still think that rod seperated in the beam under tensile loading and a defect or prior damage to the rod may have contributed. I am just not sure that Callies rod was strong enough for the use you are putting it to. Don't get me wrong here, Callies Ultra h-beam rod is a great rod and their quality is excellent.

Take a look at Wiseco's new BoostLine rod. Its beam design is stronger than the Callies H-beam and I think they deserve some consideration for your use. JMO

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