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Is this what I think it is?..cracked block

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Old Sep 14, 2010 | 08:59 PM
  #1  
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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...
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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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Old Sep 14, 2010 | 09:03 PM
  #2  
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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.
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Old Sep 14, 2010 | 09:03 PM
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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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Old Sep 14, 2010 | 09:41 PM
  #4  
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Re: Is this what I think it is?..cracked block

Originally Posted by Atilla the Fun
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.
How long should a jb weld temp fix last?
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Old Sep 14, 2010 | 10:41 PM
  #5  
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Re: Is this what I think it is?..cracked block

Not long enough to cover the cost of the JB Weld!!!!!
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Old Sep 14, 2010 | 10:55 PM
  #6  
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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...
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Old Sep 15, 2010 | 06:22 AM
  #7  
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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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Old Sep 15, 2010 | 07:02 AM
  #8  
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Re: Is this what I think it is?..cracked block

Originally Posted by jprix
How long should a jb weld temp fix last?
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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Old Sep 15, 2010 | 08:19 AM
  #9  
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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.
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Old Feb 26, 2011 | 05:08 PM
  #10  
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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.
Attached Thumbnails Is this what I think it is?..cracked block-001.jpg   Is this what I think it is?..cracked block-002.jpg  
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Old Feb 26, 2011 | 05:37 PM
  #11  
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Re: Is this what I think it is?..cracked block

Originally Posted by Denis.V
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.
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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Old Feb 26, 2011 | 05:52 PM
  #12  
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Re: Is this what I think it is?..cracked block

Originally Posted by jprix
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?
Most definitely a crack, check the coolant level, fill it if its not full, then run it bit and check the oil for coolant, it will be milky if there is coolant in it, also check the oil right off the bat, might already have it in there, if there is coolant in the oil you are SOL, if not you can have the block welded. But I am almost positive you can't weld a crack if coolant is in the oil as that won't solve that issue afaik.
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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Old Feb 26, 2011 | 07:10 PM
  #13  
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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.
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