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Discussion Starter #1
So I took out my nova today and drove it til it hit operating temp, then it just kept climbing to over 240 degrees.. I was very close to home to home so I took it back to garage. I open the hood and noticed the valve cover breather/oil cap was hissing steam like overheating... I checked the radiator and it was missing 2 gallons of coolant..then I check my dip stick and saw the oil level much higher then normal and it was like a milky mud substance. I also then took out all my spark plugs to see if I had water in there, but all plugs were gone dry.. what u guys think bad intake gasket? Oh and by the way its bbc dart motor 548 with brodix heads and cometic head gaskets.
 

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So I took out my nova today and drove it til it hit operating temp, then it just kept climbing to over 240 degrees.. I was very close to home to home so I took it back to garage. I open the hood and noticed the valve cover breather/oil cap was hissing steam like overheating... I checked the radiator and it was missing 2 gallons of coolant..then I check my dip stick and saw the oil level much higher then normal and it was like a milky mud substance. I also then took out all my spark plugs to see if I had water in there, but all plugs were gone dry.. what u guys think bad intake gasket? Oh and by the way its bbc dart motor 548 with brodix heads and cometic
So I took out my nova today and drove it til it hit operating temp, then it just kept climbing to over 240 degrees.. I was very close to home to home so I took it back to garage. I open the hood and noticed the valve cover breather/oil cap was hissing steam like overheating... I checked the radiator and it was missing 2 gallons of coolant..then I check my dip stick and saw the oil level much higher then normal and it was like a milky mud substance. I also then took out all my spark plugs to see if I had water in there, but all plugs were gone dry.. what u guys think bad intake gasket? Oh and by the way its bbc dart motor 548 with brodix heads and cometic head gaskets.
I would pressurize your coolant system with a pressure tester to around 14-15 psi and see where your losing coolant.
 

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I dont have one and I already took off the spark plugs and valve covers and drained the oil... I'm leaning towards a bad intake gaskets I hope I'm right.. I can do a compression test I have that to see if any pistons vary in pressure..
 

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I would pressurize your coolant system with a pressure tester to around 14-15 psi and see where your losing coolant.
I dont have one and I already took off the spark plugs and valve covers and drained the oil... I'm leaning towards a bad intake gaskets I hope I'm right.. I can do a compression test I have that to see if any pistons vary in pressure..
Ok, that would work. Otherwise, reinstall your plugs, pressurize and remove one plug at a time until you find it. This way you know which cylinder bank needs the gasket.
 

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Discussion Starter #5
Ok, that would work. Otherwise, reinstall your plugs, pressurize and remove one plug at a time until you find it. This way you know which cylinder bank needs the gasket.
What if l dont find any coolant from the pressure test, does that mean it would be the manifold gaskets... because back in the day I had and issues with milky oil but I saw the coolant in my tail pipes and spark plug... at this point I only see milky oil , low coolant, and no difference in exhaust.. the exhaust is perfectly normal smell and color
 

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What if l dont find any coolant from the pressure test, does that mean it would be the manifold gaskets... because back in the day I had and issues with milky oil but I saw the coolant in my tail pipes and spark plug... at this point I only see milky oil , low coolant, and no difference in exhaust.. the exhaust is perfectly normal smell and color
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What if l dont find any coolant from the pressure test, does that mean it would be the manifold gaskets... because back in the day I had and issues with milky oil but I saw the coolant in my tail pipes and spark plug... at this point I only see milky oil , low coolant, and no difference in exhaust.. the exhaust is perfectly normal smell and color
It sounds to me like a head gasket issue. That would explain your findings. If your oil on the dipstick pops and crackles when heated with a match, you have water in your oil. Pressure testers can be rented from a parts store to help you find which bank has the issue, since you have drained the oil you can’t do a compression test.
 

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Discussion Starter #7
So my question is why do people say its head gaskets automatically.. just because milky oil it does not mean its head gaskets.. I'm thinking if its head gaskets I would have some symptoms of plugs fouling or white smoke, sweet smelling radiator steam.. I have none of those symptoms... I just stopped at auto zone they rented out a pressure radiator tester to me I will see later tonight what it is..
 

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So my question is why do people say its head gaskets automatically.. just because milky oil it does not mean its head gaskets.. I'm thinking if its head gaskets I would have some symptoms of plugs fouling or white smoke, sweet smelling radiator steam.. I have none of those symptoms... I just stopped at auto zone they rented out a pressure radiator tester to me I will see later tonight what it is..
I hope you find it tonight. Just seems like it to me with that much coolant loss. The only other way to lose coolant in the cylinder head, is for the coolant to sneak up the head bolts if they were not prepped with RTV. I am talking about the bolts that go into the coolant passage, not the ones in a blind hole. Let us know how you make out with the big block.
 

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Like said - - I wouldn't do the comp. cyl test . . but the radiator test may tell you . Back along time ago - - like the late 70's , my younger sister had a 68 LeMans.
That car would "throw-up & puke that Mud" into the air cleaner . I'd clean things up & go around the block . . . . . more mud ! !
I just assumed a head gasket ; plus, I wanted too clean that block out . . . after that happened . I can't remember if I checked for a bad head-gasket . . . but
I just tore-it-down & went all the way through-it .

So, My guess - - ' Head Gasket ' . . . . . . . hope I'm wrong . . . . . . jim
 

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Discussion Starter #11
Like said - - I wouldn't do the comp. cyl test . . but the radiator test may tell you . Back along time ago - - like the late 70's , my younger sister had a 68 LeMans.
That car would "throw-up & puke that Mud" into the air cleaner . I'd clean things up & go around the block . . . . . more mud ! !
I just assumed a head gasket ; plus, I wanted too clean that block out . . . after that happened . I can't remember if I checked for a bad head-gasket . . . but
I just tore-it-down & went all the way through-it .

So, My guess - - ' Head Gasket ' . . . . . . . hope I'm wrong . . . . . . jim
I hear u , but the 2 times I ever blew head gaskets, there has to be smoke, or smell or radiator coolant or actual coolant in the cylinders making a plug wet.. I do not have no such symptoms other then low coolant and milky oil.. which means it's not coming in contact with the combustion chamber...
 

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I dont have one and I already took off the spark plugs and valve covers and drained the oil... I'm leaning towards a bad intake gaskets I hope I'm right.. I can do a compression test I have that to see if any pistons vary in pressure..
This would be my first check
 

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Mike - 74 Nova Baltimore, MD
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It is very possible that the coolant leaking into your oil was caused by the intake manifold gasket.
I had a similar type of situation happen to me. Luckily, my coolant leak from the intake gasket was towards the outside of the engine and was simple to spot once it happened.... but the coolant leak could have easily gone into my lifter valley (if the tear was on the opposite side of the gasket) causing the same scenario you are now experiencing. Below is what I saw when I removed the intake manifold.
399750

Notice the tear in the gasket (red arrow). When you remove your intake, be sure to check for any obvious signs of gasket damage.

My intake gasket leak was caused by my own doing. When I installed my motor using an engine hoist, I had already attached the intake to the motor prior to dropping it into my Nova (the intake manifold is under the white towel). I also preinstalled the automatic transmission and had to tilt the motor and trans into the engine bay. I now realize this tilting of the motor/trans combo caused the engine hoist chains to place a lot of load on the rear of the intake manifold. The load on the intake manifold must have caused the intake gaskets to deform. See image below.
399751

The thing was, it took a few years after I installed the motor for it to leak coolant... and when it did start to leak, it was a lot of fluid all at once. Luckily for me, I was pulling into my driveway when this happened (what are the chances of that).

I agree that if you blew a head gasket, you would probably be experiencing some of the other multiple issues that you have already mentioned... but it would not hurt to do a compression check.

Do you have a coolant recovery system that you check regularly?... or regularly check you coolant level in the radiator?
The reason I'm asking is that if the leak was caused by "seeping" head bolts... or a bad head gasket coolant seal (but not a blown head gasket), I would think that the coolant leak would be slow and you would have noticed the coolant level dropping before reaching the 2 gallon missing mark.
 
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Discussion Starter #14
I just bought the car, so I never checked for coolant until today ... thanks for the info brother.. u look like you know what your talking about..
 

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Mike - 74 Nova Baltimore, MD
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Hopefully it's just the intake gasket (and not something much worse).
Please keep us posted on what you find out.
 

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Pull the intake and look around. It will have to come off anyway.
I'd ck w/ Brodix and the maker of you intake and see what intake gasket they specify. See if they are the same.
Personally I like FelPro Print-o-Seal but they have to seal at both the intake and head no matter the brand.
Lastly, when the intake is off and the oil drained, pour diesel fuel in the valley till it come out of the drain hole clean.
 

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Discussion Starter #17
Pull the intake and look around. It will have to come off anyway.
I'd ck w/ Brodix and the maker of you intake and see what intake gasket they specify. See if they are the same.
Personally I like FelPro Print-o-Seal but they have to seal at both the intake and head no matter the brand.
Lastly, when the intake is off and the oil drained, pour diesel fuel in the valley till it come out of the drain hole clean.
It's a brodix intake and brodix heads.. and yes I will pour diesel in the lifter valley when I'm at it.. I remember my uncle doing that when I was young ..
 

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Check your head bolts also. I had a head bolt come loose one night bracket racing and made it all the way to the finals. I would add water every round and it would slow down a little more. I was in a dragster and would dial it up and run the finish line. I figured it was hurt any way so I just kept running it. I tore into it the next day and found the head bolt all the way loose. I did take the pan off and check the bearings but everything looked good. If you don't find a intake gasket or bolt problem you are going to have to make a decision. If the intake gasket is leaking bad enough to put that amount of water in the oil it should be identifiable. If it was mine and I wasn't sure it was the intake gasket I'd hate to put it all back together only to have to take it back down to look for a head, head gasket or block problem.
 

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Discussion Starter #19
I just did a radiator pressure test.. with the valve covers off I am able to hear a load hissing sound in the lifter valley under the intake manifold.. I have not taken off the intake yet but it looks good
 
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