Freeze plugs
 

Ok, here is my delima. I have a gen 5 BBC, I have a few oil leaks to work out so I pulled the engine this fall. I have the engine on a stand with the valve covers, oil pan and manifolds removed. I pulled the drain plugs on the block and the water started draining. I assumed it would continue to drain but the right side apparently clogged up. So here is the bad part, the freeze plugs popped out of the right side of the engine, the side with the starter. I am going to have it magnifluxed, what do you guys think?

Not a good sign, sounds like it froze at some point. Get it checked.

Ohh yea, it definatly froze on the one side. Water level was about half drained though.

if the plugs pushed out, they did their job.

From a previous post. Do a search on this topic.

The term "freeze plug" is wrong. They aren't there to keep the block from cracking if frozen. It just happens that they sometimes pop out when the coolant freezes.
Proper term is 'Core Plug". That's how the foundry gets the sand core out after casting the block.

You are doing the correct thing by testing the block. If you don't see a crack you probably will be good.

WRONG!!!!!!!!!!!!

X 2 What jim said

Good idea. You can also have them pressure tested. Man that sucks.

Yea, I will probably do both. Problem is the engine is fully assembled, to magneflux you have to use iron dust. Not good for the internals. I was just woundering were the problem areas are.

Pressure test will tell the story fast , and easy to do. If it will not hold pressure it will have to come apart anyway. good luck

If it broke you should be able to see it pretty clear along the outside of the block

Outside of the bock is visually not cracked. Someone said the lifter area may crack. How are you guys pressure testing? Do you plug off the water inlets and thermostat housing the run air pressure? I would think about 25-30 psi.

I don't think that would happen with one side half full. Look close at the top of the block where the heads bolt on. That's where the last motor I bought had broken at. Sadly it was inside and out.

I've seen them crack at the bottom of the water jacket between where the camshaft runs and the water jacket.
Block has to be completely disassembled and upside down to see this area good.

your opinion vs another on the interweb

Read post #5 and learn something today.:rolleyes:

Here is what I am going to do first. I ordered AN fittings to cap everthing off then fill it up with RV antifrieze and presurize to 30psi. Check for leaks and cross fingers.

:Whatever:

I surely would never depend on a freeze plug to save my block, but????http://www.automedia.com/Replacing_a...cr20070401fp/1

Sounds like your headed in the right direction jeff.

Don't go too high that you risk blowing past your intake gaskets and give you a false sense of damage. A buddy popped his plugs (freeze/core :) ) last winter do to late winterizing. He lucked out and did no damage.
I press checked mine before using torque plates, but that requires a big teardown.
Good luck!

You will not need 30psi to see if it is leaking , half of that will be more than lots . good luck

Thanks guys thats good to know, I will try 20 PSI and see what that does. It seemed like 30 PSI was the water pressure when running not sure may have been 25.

I have yet to see the freeze plugs push out and the block not be cracked. I hope for your sake that it isn't cracked, but I'm not holding my breath. Most of the time they will crack in the lifter valley. Good luck. Let me know if I can help.
Eddie

seen several pop out and not crack..one guy did not find out till after running for some time, noticed sluggesh performance, boat was full of water..bilge pump not working either..had popped the one out behind the starter..but block was fine...

Good news so far, I drove the freeze plugs back in. Capped off all the open ends, filled with RV antifrieze, added 20 PSI of air and no leaks.