'68 318 - Coolant left in heads when removed.

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Traxfish

Traxfish

Convertible Cruiser
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I removed the heads from my 1968 318 Barracuda to take them to the shop and when I removed the heads a LOT of coolant spilled out, even though I let the radiator drain down completely. I can also see sitting coolant in the passages in the block. Is this normal? What is causing this?

This made a mess that I immediately cleaned up. I also am unsure if any coolant could have gotten in the oil. I believe the oil ports are all above the cylinders where oil would ramp down the head to the block over the cam. Should I also change the oil?
 
There are pipe plugs on either side of the block that you may or may not be able to remove. They drain the majority of the coolant from the block.
Its good practice to change oil if engine has been opened up. If you remove intake manifold or anything below. Timing cover too.
 
Tooljunkie said:
There are pipe plugs on either side of the block that you may or may not be able to remove. They drain the majority of the coolant from the block.
Its good practice to change oil if engine has been opened up. If you remove intake manifold or anything below. Timing cover too.
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Do you mean the freeze plugs? Or another plug?
 
Traxfish said:
Do you mean the freeze plugs? Or another plug?
Click to expand...

Another plug.

There is a screw-in pipe-plug (both sides) just above the oilpan rail, towards the forward side of the midline of the block, between the front two freeze-plugs.
The removal tool might be any of three; square socket, hex wrench, or square drive.
If the engine is installed, they are sometimes hard to access, because of their proximity to the engine mounts.

Draining the rad still leaves a lot of coolant in the block.
 
AJ/FormS said:
Another plug.

There is a screw-in pipe-plug (both sides) just above the oilpan rail, towards the forward side of the midline of the block, between the front two freeze-plugs.
The removal tool might be any of three; square socket, hex wrench, or square drive.
If the engine is installed, they are sometimes hard to access, because of their proximity to the engine mounts.

Draining the rad still leaves a lot of coolant in the block.
Click to expand...
Exactly, and pulling the coolant plugs in the block rarely get you anywhere. There is usually a pile of foundry sand and sludge inside that is sometimes tough to get out. And watch out poking screwdrivers and the like in there. You could do some damage.
 
Yep, the pipe plugs will yield nothing in an old block unless the guy has removed them before and dislodged the cement behind them. You can with a screwdriver but dont hammer it in, just poke and turn to root the sediment out and be prepared for a jet of nasty coolant to follow it! I took about a pound of crap out of a 64 273 block when I took all the core plugs out, especially the 2 in the trans flange, and a few core wires.
 
pishta said:
Yep, the pipe plugs will yield nothing in an old block unless the guy has removed them before and dislodged the cement behind them. You can with a screwdriver but dont hammer it in, just poke and turn to root the sediment out and be prepared for a jet of nasty coolant to follow it! I took about a pound of crap out of a 64 273 block when I took all the core plugs out, especially the 2 in the trans flange, and a few core wires.
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Yep, Core wires. Like "WTF" when you find them for the first time.
 
IMG_2358.jpg

This is a 68 engine. At the right of the motor mount bolt you will see a boss in the block with the mentioned pipe plug. It is not un-common that even after removing, the rust deposits will have formed and nothing will come out.A coat hanger jabbed in will loosen debris.Now may be the time to think about pulling and replacing the freeze plugs.You will be amazed of the crap that you can dig out of a 50+year old block.
 
Darter6 said:
View attachment 1715780513
This is a 68 engine. At the right of the motor mount bolt you will see a boss in the block with the mentioned pipe plug. It is not un-common that even after removing, the rust deposits will have formed and nothing will come out.A cost hanger jabbed in will loosen debris.Now may be the time to think about pulling and replacing the freeze plugs.You will be amazed of the crap that you can dig out of a 50+year old block.
Click to expand...

Thanks! That's really helpful.
The engine is still in the car right now, and from what I'm reading I may save messing with the plug at a later date, when I am ready for an engine pull and tear down. I am sure there is a lot of junk in my block, though.

If I could ask for another favor, could you show where the timing marks are in a '68? As I understand it they moved on 69 and later small blocks, being on the right side of the timing chain cover, but I've not been able to find them on my 68.
 
68 is on passenger side and can either be molded into the cover or a tab bolted to the cover. 69 moved over to the drivers side.
 
if you want some more coolant out of the block before reassembly roll a piece of paper shop towel into a length and poke one end into the coolant in the block, letting the other end hang down outside the block. capillary/syphon action will draw the coolant along the paper and it'll drip off of the end hanging down. it'll drain like that until the end inside no longer is in any coolant. now the had gasket face can be dried and cleaned for reassembly.
 
Traxfish said:
I removed the heads from my 1968 318 Barracuda to take them to the shop and when I removed the heads a LOT of coolant spilled out, even though I let the radiator drain down completely. I can also see sitting coolant in the passages in the block. Is this normal? What is causing this?

This made a mess that I immediately cleaned up. I also am unsure if any coolant could have gotten in the oil. I believe the oil ports are all above the cylinders where oil would ramp down the head to the block over the cam. Should I also change the oil?
Click to expand...
Happens. Change the oil, no big. Costs maybe 30 bucks. The coolant in and out are up at the water pump ...so anything below 'aside from what's in the radiator' isnt going escape ..till you pull it, put it on the stand and tip it over into a catch pan.
 
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IMG_2357.jpg

Just right of the fuel pump is the timing tab. Set and marked in white at TDC.Best photo I got.
 
furrystump said:
68 is on passenger side and can either be molded into the cover or a tab bolted to the cover. 69 moved over to the drivers side.
Click to expand...
'69 still has the timing indicator on the passenger side too. Early '68 and older had a bolt-on tab for the timing indicator. Late '68 started the cast-in-cover version which continued through the '69 model year. Starting in the '70 model year, the timing indicator was still cast in the cover, but, moved over to the driver's side.
 
Need to drain each side of the block before removing heads or you will have a coolant bath.

Use a 9/16” 6 point socket on the plus so you don’t round them off. Best to use a 1/2” drive breaker bar to get them loose. Try tightening also to pop them loose.

Factory block plugs were a 9/16 hex. Aftermarket could be an Allen head or a square head. Don’t use pliers or a crescent wrench, you will ruin the head and not get it out. They do sell 8 point sockets for square plugs.
Use anti seize compound when they go back in. And they don’t need to be tighter than 30-35 ft lbs.
C9FD98F5-D184-4408-84D1-C22D0C0AAE5C.jpeg
 
I like to just knock out an easy to get to freeze plug and clean out the block that way. I've seen many of those block plugs get wrung off trying to get them out.
 
Darter6 said:
View attachment 1715780600
Just right of the fuel pump is the timing tab. Set and marked in white at TDC.Best photo I got.
Click to expand...
Thanks, I think that tab has broken off or been removed at some point. I rotated the engine so piston 1 is tdc and the distributor is pointing forward. The timing mark on the balancer is in the same spot but there is no tab there. I'll take a closer look to see what happened when I get home.
 
Traxfish said:
I removed the heads from my 1968 318 Barracuda to take them to the shop and when I removed the heads a LOT of coolant spilled out, even though I let the radiator drain down completely. I can also see sitting coolant in the passages in the block. Is this normal? What is causing this?

This made a mess that I immediately cleaned up. I also am unsure if any coolant could have gotten in the oil. I believe the oil ports are all above the cylinders where oil would ramp down the head to the block over the cam. Should I also change the oil?
Click to expand...
Almost all V8 engines do the same. Part of the problem is the bottom of the water pump outlets are fairly high on the front of the block. You may have some coolant in pockets by the lifters. Soak it up with a shop rag. You should be able to carefully remove the iol drain plug to drain out any coolant in the pan. If you drain half to a full quart of oil, not a big problem. Soak up coolant in the cylinders and blow out all sealed bolt holes (not open to the coolant). Then when you get it back together, run it for 20 to 30 minutes to get it warmed up. Change the oil. In about 1,000 miles change oil again. It takes a bit to get the coolant out of everywhere.
We had to deal with coolant contamination on the Detroit Diesel 92 series engines. Being a 2 stroke they had coolant seal rings just above the intake ports. In those engines the exhaust valves in the heads open a few degrees before the rings uncover the ports to blow down the cylinder. This meant there was still hot combustion gas in the cylinder by the seal rings. Eventually they deteriorated and leaked into the airbox. DD had also plumbed the airbox drains back into the oil pan to stop oil puddles under idling trucks overnight. Coolant in the oil is "corrosive" to bearings. When we overhauled these engines we used a bit of an industrial cleaner component called butyl cellosolve. This has a distinctive odour. We used only about 1/4 cup in 5 gallons of 10 weight oil and ran the engine for about 15 minutes. Then changed the oil and filter again with the regular weight oil. Probably hard to get a few ounces of butyl cellosolve so just change as I recommended.
As a note, ex wife had a 77 Impala with a 350. Change oil and drive around the block and it looked like it had 5,000.miles on it. Brought home a few ounces of butyl cellosolve and put it in the oil. Drove around for about half hour under light load before changing the oil. That cleaned out the engine and the oil would be dark brown at 3,000 mile oil change, instead of crow's butt black.
 
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