what causes a hairline crack?

6

66nathen

New Member

Jan 10, 2007

27

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0

Mar 2, 2007

#1

• Mar 2, 2007

• #1

66, 289, 302 heads and rods......had a blown head gasket....got it fixed...still have coolant getting into my oil. Shop thinks its a hairline crack...they said they're high pressure overnight tests showed no signs of moisture left from the blown head gasket. a week later i get milky oil again. now they want it for 3 days or so for more testing. So my question is, what causes a hairline crack?

 

hotrodredneck

New Member

Jul 28, 2004

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Newport News Va

Mar 2, 2007

#2

• Mar 2, 2007

• #2

a lot of things could cause it, detonation, overheating, poor handling of the head before it got to you...bad casting, bad machine work...the list goes on

 

6

66nathen

New Member

Jan 10, 2007

27

0

0

Mar 2, 2007

#3

• Mar 2, 2007

• #3

when i had my head gasket fixed, they sent the heads to another shop for checks, cleaning and other work. could they have cracked it possibly?

 

hotrodredneck

New Member

Jul 28, 2004

200

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Newport News Va

Mar 2, 2007

#4

• Mar 2, 2007

• #4

hard to say....no way you would be able to pin it on them, since so many things could have done it...heck even torquing it down wrong could have done it

 

ratio411

Founding Member

Apr 21, 2002

3,870

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109

Pensacola FL

Mar 2, 2007

#5

• Mar 2, 2007

• #5

How are you using 302 rods in a 289?
They are too short for a 289 crank...

 

F

ForceFed70

That's why they call it "dope"

Founding Member

Dec 6, 1999

4,818

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69

BC Canada

Mar 2, 2007

#6

• Mar 2, 2007

• #6

Are you sure it's not the head gasket again? Always take what a shop tells you with a grain of salt. Especially when it comes to a failed fix, or reoccuring problem.

Last time this sort of thing happened to me it was because of a warped cylinder head causing poor head gasket seal.