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Author Topic: 1178 Crank Question  (Read 7387 times)

Dusk_Blue_Z

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1178 Crank Question
« on: March 03, 2018, 02:12:16 AM »
I have two 1178 cranks that haven't been ground. Brought them to a crankshaft shop and they magged both of them and found many small hairline cracks. Is that normal for these particular cranks? Thanks.

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69Z28-RS

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Re: 1178 Crank Question
« Reply #1 on: March 03, 2018, 04:36:58 AM »
I would guess that the 'hairline cracks' are only in the surface of the journal, unless the machinist had a better idea... turning them 0.010 might totally take care of them?   
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bcmiller

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Re: 1178 Crank Question
« Reply #2 on: March 03, 2018, 03:21:53 PM »
They found hairline cracks, but what else did the say or recommend?
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Dusk_Blue_Z

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Re: 1178 Crank Question
« Reply #3 on: March 03, 2018, 06:14:33 PM »
They said I could have them ground but they won't warranty/guarantee that they would come out clean. I'll get one of them ground and see how it comes out.

I just found it odd that cracks were prevalent in both. Makes me think small hairline cracks are 'normal' for these cranks. Thanks for the replies.
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69z28302

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Re: 1178 Crank Question
« Reply #4 on: March 14, 2018, 01:42:21 AM »
I would get a second opinion from a different shop and see what it say's
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Tx-Z 302

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Re: 1178 Crank Question
« Reply #5 on: March 15, 2018, 01:48:00 AM »
I'm curious if it isn't heatchecks vs cracks, I would get a second opinions to the value of the cranks.
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Chris W

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Re: 1178 Crank Question
« Reply #6 on: March 15, 2018, 02:37:51 AM »
It could be a function of 'heat' and the tufftride surfaces put on those cranks;  I think cutting a few thousands will eliminate both... :)
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Stingr69

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Re: 1178 Crank Question
« Reply #7 on: March 15, 2018, 12:59:11 PM »
50 years of 1178 cranks and you have TWO outliers????  Second opinion is warranted. 
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L78 steve

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Re: 1178 Crank Question
« Reply #8 on: March 16, 2018, 01:55:27 AM »
Thump the flange end of crankshaft on a concrete floor. It will have a distinct sound if its cracked. Your crank shop should know this.
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bcmiller

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Re: 1178 Crank Question
« Reply #9 on: March 16, 2018, 09:56:13 AM »
Find a different shop.
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Bryon / 1968 Camaro SS 396 coupe - now old school 468 big block
1967 Camaro RS/SS 396 coupe L35/M40 - 4 generation family project
Looking for 68 Camaro with body # NOR 181016

Kelley W King

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Re: 1178 Crank Question
« Reply #10 on: March 16, 2018, 03:14:36 PM »
I think I would look elsewhere also. I have had 2 sets of heads deemed worthless by two different people. Running both today.
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Arch Stanton

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Re: 1178 Crank Question
« Reply #11 on: March 16, 2018, 11:22:41 PM »
Did he say they were junk, but still offered to take them off your hands?
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