Broke connecting rod?

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lance flake
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Re: Broke connecting rod?

Post by lance flake » Mon Sep 24, 2018 10:44 pm

MELWAY wrote:
Mon Sep 24, 2018 10:25 pm
What were 3 centre main bearings like?

If there was an ignition problem with not firing or burning the methanol you would think it would flex crank and hurt:wipe the centre main bearings
Will look tomorrow. Been trying to finish up other stuff while thinking abou this time one!

lance flake
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Re: Broke connecting rod?

Post by lance flake » Mon Sep 24, 2018 10:46 pm

blackflag wrote:
Mon Sep 24, 2018 10:29 pm
Lance I’m pretty sure the rod just broke. I’m not claiming to be an expert but I’ve seen the same problem with just about every brand rod made and I’m talking about rods with big ends still on crank and pins still round. No burnt bearings all of these rods that broke had one thing in common. They were getting the hell run out of them. They all will break. Just hope it’s not on your watch when the do.
Man that is very possible. I just want to make sure I have looked at every option. We gonna start over just don’t want to miss anything

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Re: Broke connecting rod?

Post by lance flake » Mon Sep 24, 2018 10:48 pm

He said his last engine that broke a rod had #3 broke and #4 bent. I’m gonna go take a look at that stuff and compare to this one

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Re: Broke connecting rod?

Post by Kevin Johnson » Mon Sep 24, 2018 11:58 pm

lance flake wrote:
Mon Sep 24, 2018 9:52 pm
4/7 swap

It was #7
Right now you have several mysterious engine failures after a long period of stability.

Was there a new inexperienced crew member added?

Maybe replacement wires were purchased that were not cut to specific lengths and instead loomed so that inductive misfires could occur.

Carefully examine the spark plug wire set. There are many. many counterfeit products now and the wires may not have anywhere near the expected insulation value which would aggravate inductive misfiring or even allow shorting directly to the block.

https://dragillustrated.com/di-classic- ... -concerns/
Last edited by Kevin Johnson on Tue Sep 25, 2018 12:26 am, edited 1 time in total.

MELWAY
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Re: Broke connecting rod?

Post by MELWAY » Tue Sep 25, 2018 12:19 am

lance flake wrote:
Mon Sep 24, 2018 10:46 pm
blackflag wrote:
Mon Sep 24, 2018 10:29 pm
Lance I’m pretty sure the rod just broke. I’m not claiming to be an expert but I’ve seen the same problem with just about every brand rod made and I’m talking about rods with big ends still on crank and pins still round. No burnt bearings all of these rods that broke had one thing in common. They were getting the hell run out of them. They all will break. Just hope it’s not on your watch when the do.
Man that is very possible. I just want to make sure I have looked at every option. We gonna start over just don’t want to miss anything
I dont buy into ‘the rod just broke’
There has to be a physical scientific reason as the why
Maybe that is a metallurgical flaw in steel that could not be seen by eye or a sharp notch where a fatigue crack started
3370lb Sedan 9.89@136MPH 358chevN/A

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Re: Broke connecting rod?

Post by MadBill » Tue Sep 25, 2018 12:30 am

Kevin Johnson wrote:
Mon Sep 24, 2018 11:58 pm
lance flake wrote:
Mon Sep 24, 2018 9:52 pm
4/7 swap

It was #7
Right now you have several mysterious engine failures after a long period of stability.

Was there a new inexperienced crew member added?

Maybe replacement wires were purchased that were not cut to specific lengths and instead loomed so that inductive misfires could occur.

Carefully examine the spark plug wire set. There are many. many counterfeit products now and the wires may not have anywhere near the expected insulation value which would aggravate inductive misfiring or even allow shorting directly to the block.
With a 4/7 swap, #2 is the 'at risk' cylinder and apart from not running #s 4 & 2 wires closely parallel, the only fix is RFI wire coverings, which I don't believe are used except on some plastic cars...
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.

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Re: Broke connecting rod?

Post by Kevin Johnson » Tue Sep 25, 2018 12:43 am

http://garage.grumpysperformance.com/in ... swap.5508/

Cylinder eight could induce a misfire in seven if the wires were loomed in parallel. I know not doing this is second nature to the people here but an inexperienced new crew member might make this error. Or an experienced one that assumed a quality plug wire that really wasn't.

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Re: Broke connecting rod?

Post by MadBill » Tue Sep 25, 2018 1:08 am

I was referring to the fact that no amount of electrical insulation will suppress the changing electromagnetic field that induces current in a parallel conductor.
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.

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Re: Broke connecting rod?

Post by Kevin Johnson » Tue Sep 25, 2018 1:26 am

Right, but in a 4/7 swap (18736542) there are potential inductive misfires for 1-8, 8-7, 7-3, 3-6, 6-5, 5-4, 4-2 and 2-1. Here the hypothesis is that 8 induced a misfire in 7. In the other engine failures other inductive couplings could have occurred.

As for deteriorating insulation that could allow actual electrical conductance between adjacent wires (parallel or crossing, say) my experience is anecdotal with cell phone accessories. I have purchased adaptors that when left in the car interior heat had the once flexible wiring turn to a crumbling mess. Name brand products (purchased at an Apple store) have lasted for many years in the same environment. I first ran into this personally when redoing all the vacuum hoses on a Turbo LeBaron about twenty years ago. All the replacement hose quickly turned hard as rock and cracked. With fake merchandise appearance is king.

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Re: Broke connecting rod?

Post by Newold1 » Tue Sep 25, 2018 11:32 am

Lance:

Maybe some truthful expression and honesty might surface with a phone call to Callies.

Ask Callies is it possible with all the Ultra rods they manufacture to have a few rods reach the market place that might have a slight internal flaw in grain structure and strength that might experience failure in high rpm and loading situations. If they answer that question by saying that is not possible, I am sorry but they are lying! No rod manufacturer who produces aftermarket high performance rods with standard industry testing and quality control methods and who produces thousaands of those rods CAN say that truthfully! That is just a fact!

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Re: Broke connecting rod?

Post by Frankshaft » Tue Sep 25, 2018 11:47 am

The rod just broke. Move on with your life. Thread over. Lol

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Re: Broke connecting rod?

Post by Warp Speed » Tue Sep 25, 2018 7:07 pm

Frankshaft wrote:
Tue Sep 25, 2018 11:47 am
The rod just broke. Move on with your life. Thread over. Lol
:lol:


Hard to tell from the picture, but it almost looks like a big hunk of crap in the beam, at what appears to be the failure point. Surprised from Callies, but it does happen.

lance flake
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Re: Broke connecting rod?

Post by lance flake » Tue Sep 25, 2018 9:19 pm

Frankshaft wrote:
Tue Sep 25, 2018 11:47 am
The rod just broke. Move on with your life. Thread over. Lol
That would be the easy thing to do I guess. No need to do the right thing and help this guy find his issue before it happens again

lance flake
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Re: Broke connecting rod?

Post by lance flake » Tue Sep 25, 2018 9:23 pm

Newold1 wrote:
Tue Sep 25, 2018 11:32 am
Lance:

Maybe some truthful expression and honesty might surface with a phone call to Callies.

Ask Callies is it possible with all the Ultra rods they manufacture to have a few rods reach the market place that might have a slight internal flaw in grain structure and strength that might experience failure in high rpm and loading situations. If they answer that question by saying that is not possible, I am sorry but they are lying! No rod manufacturer who produces aftermarket high performance rods with standard industry testing and quality control methods and who produces thousaands of those rods CAN say that truthfully! That is just a fact!
Called Callies today. Not much help! Not wanting anything for free or a blame game was just looking for some real technical help.

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Re: Broke connecting rod?

Post by Frankshaft » Tue Sep 25, 2018 9:44 pm

lance flake wrote:
Tue Sep 25, 2018 9:23 pm
Newold1 wrote:
Tue Sep 25, 2018 11:32 am
Lance:

Maybe some truthful expression and honesty might surface with a phone call to Callies.

Ask Callies is it possible with all the Ultra rods they manufacture to have a few rods reach the market place that might have a slight internal flaw in grain structure and strength that might experience failure in high rpm and loading situations. If they answer that question by saying that is not possible, I am sorry but they are lying! No rod manufacturer who produces aftermarket high performance rods with standard industry testing and quality control methods and who produces thousaands of those rods CAN say that truthfully! That is just a fact!
Called Callies today. Not much help! Not wanting anything for free or a blame game was just looking for some real technical help.

Like I said earlier. Its all opinions and ideas. No way to know what came first, the chicken or the egg. Sorry for the failure, it sucks. There just is nothing staring us in the face to know. I think it just broke. This thread could go on for another 10 pages with no more conclusion.

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