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I got a 385 sbc that had to be rebuilt due to lots of water being in the oil. Made the second pass in the car after rebuild and lost a gallon into the pan. Heads and cylinder walls are okay and don’t have cracks. I’ve read a few places that water could be getting around the studs and the studs in my motor haven’t been touched since the 90s. I’m inclined to try and take them out to reseal them and see if it fixes the issue on top of trying morosos ceramic sealer. I also use silicone around the water passages on the intake so I doubt it would that. Does anyone have any idea what it could be.
 

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Race it, Don't rice it!
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Heads gaskets, intake gaskets, head bolts, cracks in the block and heads are about the only places water can get into the pan.
A gallon is a lot of water to pass through some leaky head studs.
 

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The only test for cracks is disassembly followed by a through shop cleaning then with magnetic or penetrating dye inspection. Simple visual eyeball looking is not sufficiently good enough.

Ported head ports are a common failure point where the grinding thins the walls to much and they fail in service.

Mixing machined parts like decked blocks and milled head’s and or mixes of this with aftermarket parts can lead to gasket sealing issues from parts that are slightly more dimensionally off that the chosen gasket can accommodate. A common one is the intake to head gasket which oft times leaks on the valley side where you can’t see it nor test for it very well.

Yes head bolts and some intake bolts penetrate into the cooling jackets and must be sealed. If you just run water for coolant or a light dose of glycol antifreeze the Teflon infused pipe sealer works well. For that condition and necessary with waterless coolant non-hardening Permatex works well. There is a dual requirement going on with these bolts of both sealing coolant out of the threads and providing a thread lubricant that emulates the factory torque spec done with engine oil. If using ARP fasteners you need to follow their directions for sealer and lube.

Poor surface of the block head deck and or of the head’s is another source of leakage as is the use of aluminum heads on an iron block with a shim style head gasket.

Another rather unique to SBC stroker type builds is a failure in those areas that are clearanced along the adjoining sections where the upper crankcase wall blends into the cylinder spigot. This as with porting is getting a too thin wall that fails in service.

So there are a lot of places where coolant gets into the engine that really require disassembly of the engine if surface inspection doesn’t lead to the cause. Pressure testing might reveal a coolant loose but sometimes these are things that open up when the engine is hot and are not doing dastardly deeds when it’s cold.

Bogie
 

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A gallon in a pass? 1/4 mile pass? Wow, that's a ton.

That isn't a head stud/bolt leaking imo. Pull the intake and see if you see where it's entering, and hopefully it's obvious around one of the intake cooling ports. If they are OK, then you have a crack somewhere.
 

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True Hotrodder
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Forget the ceramic sealer - that stuff is great for cracks but that much water from the pit space and back is a pretty serious leak. I take before this was put back together that the heads and block were checked and found okay? I would be looking at the intake gaskets and probably not a bad idea to put some air on individual cylinders and listen for leakage.
 
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