Is this what I think it is?..cracked block
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Joined: Jul 2010
Posts: 109
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From: MI
Car: 85 Trans AM
Engine: Chevy 355
Transmission: T-5
Axle/Gears: 3.73
Is this what I think it is?..cracked block
Noticed this ridge yesterday when I pulled the motor,seen antifreeze on it so I wiped it down with some brake cleaner and today I find this...



Bought the car knowing it needed a rebuild,so never drove it but had it running a couple times.
Is this easily (and cheap) fixable?



Bought the car knowing it needed a rebuild,so never drove it but had it running a couple times.
Is this easily (and cheap) fixable?
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Joined: Feb 2010
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From: Orlando
Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: Is this what I think it is?..cracked block
That does kinda look like a crack.
What I would do is hook a radiator up to the motor and fill it up with water like normal. Then rent a pressure tester from auto zone and see if water seeps out. If so, its easily fixable if your rebuilding the motor because you wont be using that block.
What I would do is hook a radiator up to the motor and fill it up with water like normal. Then rent a pressure tester from auto zone and see if water seeps out. If so, its easily fixable if your rebuilding the motor because you wont be using that block.
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From: Northern Utah
Car: seeking '90.5-'92 'bird hardtop
Engine: several
Transmission: none
Axle/Gears: none
Re: Is this what I think it is?..cracked block
That is a cracked block. That is temporarily fixable with JB weld, but the block probably has other cracks. Either take it apart, or risk coolant in the oil at minimum, or broken block, crank, et cetera, at worst.
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Joined: Jul 2010
Posts: 109
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From: MI
Car: 85 Trans AM
Engine: Chevy 355
Transmission: T-5
Axle/Gears: 3.73
Re: Is this what I think it is?..cracked block
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Joined: Jan 2009
Posts: 2,313
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From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Is this what I think it is?..cracked block
that is a crack alright,most likely from the coolant
getting frozen...IF the block is otherwize in good shape
might be worth having a welding shop used to welding
cast iron weld it up-as i understand,the block will have
to be stripped then heated in an oven to around 350-
400*,welded then cooled gradually to reduce the
chance of a new crack forming beside the old one...
There is a possibility the welding might distort the
deck and require a skim to true it back up...
getting frozen...IF the block is otherwize in good shape
might be worth having a welding shop used to welding
cast iron weld it up-as i understand,the block will have
to be stripped then heated in an oven to around 350-
400*,welded then cooled gradually to reduce the
chance of a new crack forming beside the old one...
There is a possibility the welding might distort the
deck and require a skim to true it back up...
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From: Northern CA.
Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
Re: Is this what I think it is?..cracked block
If it needs a rebuild anyway, get another block. You can probably pick one up at your machine shop for 100 bucks or so. Had to do the same when a block I dropped off checked out to be cracked in the lifter valley.
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From: Northern Utah
Car: seeking '90.5-'92 'bird hardtop
Engine: several
Transmission: none
Axle/Gears: none
Re: Is this what I think it is?..cracked block
I've done it to my own blocks. One was in the lifter valley area. It didn't open up quite that far. I cleaned it well, scuffed it with 240 grit, in 2 different directions, to give some bite, cleaned it again, then JB Welded it. That was 8 years ago. That block is still on the road, giving good service. However, it's now a 250-horse build, not a 400 horse build.
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From: Moneta, VA
Car: 88 GTA
Engine: 305 TPI
Transmission: WC T5
Axle/Gears: BW 9-bolt 3.27 posi
Re: Is this what I think it is?..cracked block
That looks exactly like the cracked block that came out of my son's car. It is definitely cracked, and if you plan to do any work to the engine, I would replace the block.
If Attila says JB Weld will give temporary relief, I'd trust him. He is the man.
If Attila says JB Weld will give temporary relief, I'd trust him. He is the man.
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Joined: May 2002
Posts: 510
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From: Santiago, CHILE
Car: 1986 Pontiac Firebird Trans Am
Engine: 305 Tuned Port Injection
Transmission: The famous 700R4
Axle/Gears: No idea
Re: Is this what I think it is?..cracked block
Hi,
A little help, please (according to this thread),
What do you think?. Is this block cracked in this cylinder wall?:
When I put my fingers in it, the wall is not flat. I feel a little cavity in it.
Thanks.
A little help, please (according to this thread),
What do you think?. Is this block cracked in this cylinder wall?:
When I put my fingers in it, the wall is not flat. I feel a little cavity in it.
Thanks.
Supreme Member
Joined: Mar 2009
Posts: 1,402
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From: Sussex County, NJ
Car: 1994 Z28
Engine: 355 LT1
Transmission: T56
Axle/Gears: 3.42
Re: Is this what I think it is?..cracked block
horrible quality pictures. is it nicked real bad? You might be able to get your fingers behind the cylinder in the coolant ports and feel it.
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From: PA
Car: 1996 Camaro, 1985 Camaro
Engine: 3.8, 3.4
Transmission: WC T5, 700r4
Axle/Gears: 3.23(?), 3.42
Re: Is this what I think it is?..cracked block
Noticed this ridge yesterday when I pulled the motor,seen antifreeze on it so I wiped it down with some brake cleaner and today I find this...



Bought the car knowing it needed a rebuild,so never drove it but had it running a couple times.
Is this easily (and cheap) fixable?



Bought the car knowing it needed a rebuild,so never drove it but had it running a couple times.
Is this easily (and cheap) fixable?
My car had a cracked block when I got it and supposedly just needed HGs for the engine, so at any rate, I sympathize...
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From: Akron, Ohio
Car: 87 Suburban 2500
Engine: 455 Wildcat ( somewhat modified ))
Transmission: TH400 ( for now )
Axle/Gears: 4.10 ( for now )
Re: Is this what I think it is?..cracked block
The side of the block looks like a water jacket expansion crack. JB Weld works wonders on that, but you have to consider the other surfaces and where the pressure went.
If it's also cracked into a cylinder, scrap that block.
You could check into a sleeve, but is it worth it ? Sleeving is very common in big diesels, so that approach is reliable, but not cheap.
If it's also cracked into a cylinder, scrap that block.
You could check into a sleeve, but is it worth it ? Sleeving is very common in big diesels, so that approach is reliable, but not cheap.
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