How do you check to see if your block/ heads are cracked?

enkeivette

enkeivette

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Joined
Mar 30, 2008
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Is there any way to do this? Some way to verify that the heads or the block is cracked as opposed to just a leaky head gasket.

And is there any way to check with the heads off but the motor in the car? I'd hate to waste a $200 Cometic HG and all that labor just to find that I have a crack somewhere.
 
Pressure test or mag fluxing on a bare block and even with the mag fluxing you may not find a small crack. However, if there's a leak the pressure test will most likely expose it (unless it's a super secret crack that opens when hot and only leaks then)
 
Do you have any pistons that look alot cleaner than the others? Coolant is great for removing carbon.
 
Get it up to operating temperature and pressure test the cooling system- as high as you can get the tester, like 20 psi. Be careful removing the cap when it's hot- or, put the pressure tester on before you start it. Pump it up to 15 PSI and let the heat do the rest.
 
TimAT said:
Get it up to operating temperature and pressure test the cooling system- as high as you can get the tester, like 20 psi. Be careful removing the cap when it's hot- or, put the pressure tester on before you start it. Pump it up to 15 PSI and let the heat do the rest.
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I can see where it's leaking, looks like it's leaking from the HG. But I was wondering if there's some way to verify that the block or heads are cracked, that is before I pull the heads off making certain testing procedures impossible.
 
That would be tough Adam. With the head gasket a known leak, the pressure test is useless.
Since you have to pull the heads to change the gasket, I would just yank them and have them checked. If you want to do the test yourself, Magnaflux makes a 3 part kit you could use. (Used on aluminum). I have a UV blacklight I can loan you.
I have been trying to remember the poor man's method. Something about cleaning, soaking in oil, wiping off, and the crack retains the oil. CRS. Gotta look some more.
 
Verify the torque on your head bolts first.

You could try this "head gasket repair" stuff and see if the leak stops..... that stuff is not compatible with anti freeze and sure is a mess....

Simply installing (one ?) cheap new head gaskets is probably the easiest method to see if it is in fact the gasket..... if it continues to leak you only lost $20 and your time....
The cheapest gasket kits at the 'zone' are how much ? $30 ??? I have a few spare gaskets for heads and intake, let me know if you want them.....

Did you overheat the engine ? Why do you think it might be a cracked head or block ??
 
MYBAD79 said:
Verify the torque on your head bolts first.

You could try this "head gasket repair" stuff and see if the leak stops..... that stuff is not compatible with anti freeze and sure is a mess....

Simply installing (one ?) cheap new head gaskets is probably the easiest method to see if it is in fact the gasket..... if it continues to leak you only lost $20 and your time....
The cheapest gasket kits at the 'zone' are how much ? $30 ??? I have a few spare gaskets for heads and intake, let me know if you want them.....

Did you overheat the engine ? Why do you think it might be a cracked head or block ??
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It just seems odd to me that after the heater hose blew all of a sudden BOTH of my head gaskets are leaking. I'm thinking that the coolant spraying over the block could have cause something to warp.

Bird, thanks for the read. I think I'm going to run some of that dye through the motor before I take it apart. This way I figure, the dye will have been forced into the cracks (if there are any) and when I take the heads off I'll be able to see them (if there are any).

Cross your fingers for me.

BTW! Now that I'm thinking about it, I'm thinking that I've had a HG leak since before the DC tour, and it's just been getting progressively worse. I remember one night months and months ago, I got on it real hard and I hit the rev limiter. The motor has always felt slightly different after that one hard pull. It would explain why my PCV and breather are always milkshakey but my oil isn't... I think. I'm thinking that a very small amount of coolant has been getting into the oil, and evaporating underneath my valve covers. Is that a possibility? And maybe the HG leak allowed cylinder pressure to increase the pressure of the cooling system which is why my heater hose blew up. Trying to play detective here but I'm just shooting in the dark.
 
The dye is a good start but eventually you will have to disassemble and inspect. Honestly: you have a 600? HP supercharged SB and from what you're posting about loosing traction in second gear it doesn't sound like you're easy on the engine :D:D:D

Hopefully it's only the HG
 
enkeivette said:
BTW! Now that I'm thinking about it, I'm thinking that I've had a HG leak since before the DC tour, and it's just been getting progressively worse. That would explain the puff of vapor during the pullIt would explain why my PCV and breather are always milkshakey but my oil isn't... I think. I'm thinking that a very small amount of coolant has been getting into the oil, and evaporating underneath my valve covers. Is that a possibility? YesAnd maybe the HG leak allowed cylinder pressure to increase the pressure of the cooling system which is why my heater hose blew up. Good guessTrying to play detective here but I'm just shooting in the dark.
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Sounds like your on track. Keep us informed. I hate it when we never know the end of the story.
 
MYBAD79 said:
The dye is a good start but eventually you will have to disassemble and inspect. Honestly: you have a 600? HP supercharged SB and from what you're posting about loosing traction in second gear it doesn't sound like you're easy on the engine :D:D:D

Hopefully it's only the HG
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My plan is to run the dye, the pull the heads off. In the hope that when I do, the dye will already be impregnated into the crack, if there are any.

big2bird said:
If he already has a leaking head gasket, I don't think it would help any.
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I already tested the cylinder near the leak, it was at 140psi. My highest cylinder is at 150psi. So it could be a leak I suppose. It did seem to take longer to get the pressure guage maxed out on that cylinder though.
 
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