One Crack In Block

300sflyer

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Hey guys,

I have a friends V6 here, with a crack in the block due to improper winterizing. I have removed the intake, and this is the only problem I can find, besides a few frost plugs pushed out.

I have never been a believer of band-aid solutions, but I'm considering JB welding it. Is this a long term viable fix, or is the crack too close to the cylinder head?

Thanks for your thoughts!


 

Bondo

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Ayuh,...... IF that's the only crack, go ahead 'n butter it up with epoxy,....

I'm guessin' you'll find more once it can build pressure though,......
 

300sflyer

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Like I said, I did pull the intake, and much to my surprise, the lifter valley has no cracks. The engine did run for a few minutes, and there was no water in the oil. This is the only crack I can find.
 

Rick Stephens

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Most common place for a V6 to crack is is in the lifter gallery. Cracks will typically run down the block immediately above the lifters.

Rick
 
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ojotaylor

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Jul 16, 2015
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If that's the only crack he's lucky. I had a crack like that on my 350, opened it up and there were cracks everywhere. Learned my lesson about buying off of craigslist. JB weld will work, just clean it with a dremmel, make a V as best as you can in the crack and wipe it down with acetone prior to applying the JBWELD. Use the original formula and let it cure for 24 hrs before you start that engine back up. Keep checking the oil for water as well.
 

Volphin

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I've seen several crack along the block as your picture indicates. No harm in trying JB if you wish, but don't get your hopes up. How are the manifolds?
 

biggjimm

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If you drill a tiny hole at the very ends of the crack (both ends) that will stop it from cracking further. Always drilled em before welding em. Never JB'd one but you might get lucky. Jim
 

300sflyer

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The manifolds are fine, they got drained properly. I have the frost plugs back in, and the repair completed with JB. I used a dremel and grinding wheel to and made a V as was suggested. Now to wait 24 hours, before I reassemble. I am then going to pressure test the cooling system, and hopefully it will hold 10-12 PSI.
 

biggjimm

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The manifolds are fine, they got drained properly. I have the frost plugs back in, and the repair completed with JB. I used a dremel and grinding wheel to and made a V as was suggested. Now to wait 24 hours, before I reassemble. I am then going to pressure test the cooling system, and hopefully it will hold 10-12 PSI.
Time to school me a bit.

If it's not a closed cooling system, will it hold pressure to check it like that?? With the cooling system tied in to the exhaust won't the pressure just equalize with the atmosphere or will the exhaust shutters seal it up???
 

Bt Doctur

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with the block correctly sealed it should hole pressure to test for any additional cracks
 

Rick Stephens

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Time to school me a bit.

If it's not a closed cooling system, will it hold pressure to check it like that?? With the cooling system tied in to the exhaust won't the pressure just equalize with the atmosphere or will the exhaust shutters seal it up???

Just have to block off the exhaust/water jacket at the risers and cap the inbound water line.
 
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300sflyer

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The cooling system held 10 PSI just fine. I then fired it up on a skid, and let it run for about 1/2 an hour. It got up to full temp after a few minutes, and stayed at 160F. The fresh oil was water free. :)
 

Rick Stephens

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The cooling system held 10 PSI just fine. I then fired it up on a skid, and let it run for about 1/2 an hour. It got up to full temp after a few minutes, and stayed at 160F. The fresh oil was water free. :)

That's awesome. Somebody stayed on the right side of the boating gods.
 

ibrw1

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Why don't I have luck like that! I would check oil every time I pulled the boat out. Why not? Good luck!
 

smokeonthewater

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Eh I wouldn't get TOO terribly jealous... After all he DID have a cracked block. ;-)

Glad it wasn't worse tho..... Congrats!
 

Bondo

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The cooling system held 10 PSI just fine. I then fired it up on a skid, and let it run for about 1/2 an hour. It got up to full temp after a few minutes, and stayed at 160F. The fresh oil was water free. :)

Ayuh,..... It might be worth playin' the lottery this week,.....
 
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