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Engine block cracks at the base of cilinders

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Hi,

I am in the process of building a j32a2 engine and when I was washing and checking the block I found these crack at the base of the cilinders.

Can someone advise:

should i be worried?

can it be fixed by grinding and welding?

Is the block junk ?

Thank you

Cristian

Attached Files

One picture with a bit of an overview where that "crack" actually is would help us.

And that doesn't really look like a real crack to me, more like some imperfections from the casting. But it really depends where that is located.

Thank you Silas for your opinion .

I made 2 new photos maybe it will help.

Some marks in the pictures are indeed casting rufness but i can assure you some of them are really small cracks.

Giving the fact that I plan on making double the amount of power than the stock block was designed for I just want to be sure my foundation its solid.

Attached Files

Well I am no expert on metallurgy but I have seen similar "cracks" on castings before and I still think that it is not a serious crack that happened from stress, but from the casting process.

Can you see how deep it goes and what is behind that spot? The outside or water jackets?

Some of those appear to be surface marks left from the casting process, but some appear to be more serious - either way, they could be stress risers in a highly loaded part of the block.

I would give them a light cleanup to smooth them out and then check if they still look like cracks and if i had any doubt, I would then have them crack tested - not a bad move for any engine that is going to be highly stressed, anyway.

Depending on the casting material, you may be able to grind out and weld the cracks, but if there is any question, I would try sourcing a new block. If there IS a failure, and that is a big "if", it will wipe out the whole of the bottom end and possibly the rest of the engine and, if you end up driving over a load of dumped oil, you could loose the whole car.

Anyway, I would strongly suggest you also ask on the forums devoted to these engines as they should have a better idea of what you can get away with and what is regarded as 'normal'' for these blocks.

Silas,

there is no visible penetration on the other side of the block.

Thank you Gordon, that was helpful!

I’ll grind/clean the surfaces and take it from there to see if there is something to worry or not!

These pics look to me like marks that are inline with the casting process and shouldn't be anything to worry about, particularly given their location.

Thank you Andre!