Are these things in my heads coolant passages? (photo)

[Secret Chimp]

I just pulled the intake off of my 318 (gaskets were leaking coolant) and found that a hole about an two inches down inside of the front coolant passages (this is the driver's side) had hard pebbly debris hiding in it.

The wider section of the passage and the intake itself are clear. Is this a secondary passage that's plugged up, or just some casting cavity that's filled up with gunk but doesn't flow anywhere? What's the best way to get this stuff out without pulling the heads Both times I've drained the system recently no funny junk came out.

 

[Secret Chimp]

Here's a better picture of what I'm talking about specifically:

You can't see the debris, but it is plugged up, and so is the same hole on the other side. Both face inwards towards the block. Does that matter? I just don't know if they're secondary coolant passages or not.

 

[Secret Chimp]

Okay, I'm a dummy. I got some bent tip pliers crammed in there and that's definitely metal just inside of there.

 

[Coronet 500]

If you put your finger in that opening you should feel a round or tear drop shaped hole going down into the block. Looking in horizontally you should see it all open and the top of #1 combustion chamber that the coolant flows around.
That debris is a mystery to me, I would take the head off and explore further.

As far as the flushing goes many I have taken apart will still have lots of sediment in the bottom of the block only loosened up while on an engine stand with long probing and agressive direct pressure to that area. Pulling the frost plugs gets you right in there.
Good luck.

 

[greenmonsta79]

Sorry but you mean "Core" plugs, just hate to hear people call them freeze or frost plugs as that has nothing to do why they are there!

 

[Coronet 500]

A football can be called a "pigskin" and has been made from deer skin or synthetics.
Don't hate, lets help.

 

[Secret Chimp]

I'm going to have to get a dentist's mirror and look in there... I want to believe you but what I'm feeling doesn't make any sense. It doesn't even feel like a blockage after I picked out the rest of the white crud, it just feels like a rounded-off dead end. Very strange.

 

[greenmonsta79]

lol, not hating just correcting.

 

[Cranky]

Sorry but you mean "Core" plugs, just hate to hear people call them freeze or frost plugs as that has nothing to do why they are there!

I've heard in the casting business that when the casting 'freezes', you can then dump the sand out through the core holes and send the frozen casting on to the next operation. I may be totally out of line with that because I never worked in a foundry but have spent some time in them and heard one guy say "when the casting freezes after cooling.....". Just saying maybe that's where the term originated.

 

[Secret Chimp]

Confirmed not to be a problem and not a passage of any kind. I got a tiny pick-up magnet from Harbor Freight and the surface inside there is flat and magnetic. There is a passage that goes down to the head, which is clear, but it's well below this thing. The debris I pulled out of my mystery area (I scraped at it a little with my bent pliers earlier) stuck to the magnet. It must be some kind of casting area or something that was filled in at the factory? At least I know I don't have quickcrete in half of my engine.

 

[shorty64]

Hmmmmm.... So the "Freeze Plugs" were also not an aid ("safety valve") for keeping blocks from cracking in the winter when using mostly water with no-little anti-freeze eh? Must have been an old wives tale.

 

[Patrick]

lol, not hating just correcting.

Correcting what? When you purchase the things they are listed as freeze or frost plugs, because thats how they are listed in the parts books.


Sealed Power Z3818011 - Sealed Power Freeze Plugs large image

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Freeze Plugs, Brass, Chrysler, Big Block, Kit
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[Patrick]

Sealed Power Z3818011 - Sealed Power Freeze Plugs large image

$12.99
+ Wish List
+ compare

Freeze Plugs, Brass, Chrysler, Big Block, Kit
Application Specific
Application Specific Part: Check Application
Estimated Ship Date: Tomorrow

 

[greenmonsta79]

They may be listed as "Freeze" plugs but as working as a counterman at Western Auto/Parts America, I can't tell you how many idiots came in and said "you gotta a freeze plug? my Chevy froze and they popped out" thinking it was a built in saftey feature!! when most people fail to realize they are actually "core" plugs as that was what they used to seal the block after they evacuated the sand from molding the water jackets!! I have seen a few engines with threaded "core" plugs (especially in high performance applications)

 

[yellowdartdave]

Ok, they are plugs designed to fit the core holes, but if the water freezes in the block, they will pop out (hopefully) rather than crack the block due to the expansion of ice.
So most people call them freeze plugs as they are not educated in the 'correct' lingo.

Just like I hate being called a 'car hauler."

I am a "New Motor Vehicle Relocation Expeditor."

 

[Cranky]

Ok, they are plugs designed to fit the core holes, but if the water freezes in the block, they will pop out (hopefully) rather than crack the block due to the expansion of ice.
So most people call them freeze plugs as they are not educated in the 'correct' lingo.

Just like I hate being called a 'car hauler."

I am a "New Motor Vehicle Relocation Expeditor."

So, you drive a portable parking lot? In my experiences with 'freeze' plugs....yeah, they pop out AND the block cracks! :angryfire: