Do I have a blown head gasket?

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straightlinespeed

straightlinespeed

Sometimes I pretend to be normal
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I pulled my intake to fix what I though was a leaking intake gasket. The bottom side of the valve covers, had a greenish sludge/slime coating them and appeared to be watery/oil. I cleaned the covers with brake cleaner and got it all out. I reassembled the engine, topped off the antifreeze, started it up and got it up to temp no leaks then took it for a 20 mile drive. I got home and sure thing the damn leak is back in the same spot, dripping down the front of where the head and block meet, and down the engine. I let it sit over night and went out and looked at it tonight. Pulled the valve cover and there is that green sludge again, not as thick as last time, but forming. I checked the antifreeze and its down pretty low. Also every time I start the car I get a lot of moisture out of the exhaust. The oil is not showing signs of having water in it.

Is this a sign of a blown head gasket?
 
Do you have access to a pressure tester? Pressurize the radiator, pull the plugs and look for the pressure drop and leak.
 
One thing I'd do next is go over the head bolts with a torque wrench, just to make sure they're all correct. Next , it would be time to pull that head!
 
I can renta pressure tester locally, that is a good idea to try.

I did check torque on the bolts and they were to spec.
 
Part of your description doesn't make sense to me. If you have the "green sludge" on the inside of the valve covers then I would think that it would be present throughout the inside of the engine. No "milky" coolant residue on the oil dip stick or in the dip stick tube? I suppose it could be possible that your intake gaskets are leaking coolant at the front intake manifold to head water passage and that the internal air pressure of the engine is forcing the coolant vapor up towards the valve cover breathers. Any "milky" coolant residue in the PCV valve and PCV valve to carb hose?

As for the possibility of a blown head gasket, a diagnostic tool that I like to use is a differential leak down tester where you pressurize each cylinder through the spark plug hole and measure the amount of air pressure leakage within the cylinder. It will tell you if you have a blown head gasket and a lot of other things too. But it doesn't really sound to me like a blown head gasket is the culprit here.
 
RzeroB said:
Part of your description doesn't make sense to me. If you have the "green sludge" on the inside of the valve covers then I would think that it would be present throughout the inside of the engine. No "milky" coolant residue on the oil dip stick or in the dip stick tube? I suppose it could be possible that your intake gaskets are leaking coolant at the front intake manifold to head water passage and that the internal air pressure of the engine is forcing the coolant vapor up towards the valve cover breathers. Any "milky" coolant residue in the PCV valve and PCV valve to carb hose?
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Yes, pcv was clogged and the tube has it as well. Pulled the carb obviously and it was creeping inside tube at the base of the carb also. Only thing with the dipstick tube has is oil creeping it's way up and out the tube, enough in a 20 mile drive to show actual drips.

This is the 4th set of intake gaskets, I've put in it. Using Edelbrock gaskets, with the magnum heads and intake. Im using rtv around the water ports and silicone across the block. The guide pins are pulled.
 
My opinion, cracked head. I cracked one in the same place judging by your description. MT
 
Did you say this is your fourth set of gaskets? Were they all changed due to failure?
 
Wouldn't a blown head gasket show up on a compression test???
 
Mopar Tim said:
My opinion, cracked head. I cracked one in the same place judging by your description. MT
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I hope this isn't the case, the heads were brand new when I had the engine built and there is only a couple thousand miles on them.

doogievlg said:
Did you say this is your fourth set of gaskets? Were they all changed due to failure?
Click to expand...

Yes, 4th set. Only because I thought I was installing them wrong and it was not sealing up on the water passages. Im starting to doubt the intake gaskets is the problem

krazykuda said:
Wouldn't a blown head gasket show up on a compression test???
Click to expand...

I'm not sure but I can do this test along with the leak down and radiator pressure test.
 
Well im ashamed to say but I cracked a new set of heads by torqueing them incorrect. If there was any liquid in the bolt hole before you assembled, the action of torqueing the bolt can crack the head where you describe it, it cracks using hydraulic compression.
 
straightlinespeed said:
This is the 4th set of intake gaskets.
Click to expand...

straightlinespeed said:
I got home and sure thing the damn leak is back in the same spot, dripping down the front of where the head and block meet, and down the engine.
Click to expand...

Hmmm? Okay, so this is your fourth set of gaskets and the leak is visible along the head block seam. Obviously the problem is in the immediate vicinity of that intake manifold to head water passage joint - but where exactly? In my opinion, if you have changed the gaskets four times it stands to reason that they are not the problem.

Has the block ever been decked? If the block has been decked and the heads and/or intake manifold have not been milled accordingly, the intake will sit up too high and could cause a sealing problem. However, this usually first manifest itself during the initial installation of the manifold when you can't get the intake manifold bolts to line up with the heads so the possibility of this being the problem may be rather remote.

As previously mentioned by another poster, a crack or porosity issue may be present in either the head or intake manifold water passage. A cooling system pressure test may reveal the crack or porosity point if it's on the externally visible part of the engine. Of course, the only way to check the internal parts would be to remove the parts and have some kind of non-destructive testing done like a dye penetrant or eddy current testing.

Before I remove anything else, I would conduct the coolant system pressure test. There is a fluorescent dye that you can buy to put in the coolant and it will help you pinpoint the leak if it is externally visible on the engine.

If the coolant pressure test was inconclusive, I would conduct a cylinder leak down test focusing on the affected side first (I don't recall if you said the visible leak was on the left or right side??). With the cylinder pressurized, if you see bubbles or hear air escaping from the coolant in the radiator top tank, then yes your head gasket is blown.
 
I honestly cant answer the questions about the block being decked. I believe it was checked for being true and straight, and the heads where right out of the box.

I did some testing tonight. First off I cleaned up the area with brake cleaner. Forgot to mention this is on the passengers side head. I did the coolant pressure test. I pumped up the system to about 14-16 lbs. Immediately the leak started showing up at the bottom of the head and block on the flat silver pad.

View attachment IMG_20150527_185607203.jpg

I looked at the front of the engine between the head and block, nothing was showing up after about 10min.

View attachment IMG_20150527_190818479.jpg

I decided to do a leak down test. I pulled all the plugs and I could tell that the piston top in the #4 cylinder was looking a little wet, but I couldnt tell if its water, or oil. Had the wife come out and look and asked her what she thought it was, she thought water right away. #6 and 8 where nice and dry looking. Damn wish I had a bore scope.

Anyways these were the #'s from the test.
2-8%
4-8%
6-12%
8-6%

I can tell you that the #6 cylinder broke some piston rings on initial break in so the engine shop had to repair that. Probably why the slightly higher #.

Anyways, none of the cylinders caused bubbles in the radiator and didnt sound out of the ordinary from one another.

So I went back to the coolant pressure test. This time I pumped it up to about 17-19lbs. Its been on there for about a half hour. The leak on the bottom of the head and block is getting bigger and starting to drip down onto the k frame.

I did not do a cylinder compression test yet, but I can if needed. I can tell you that Im at about 185psi when I checked #1 a couple weeks ago. This got me thinking, Ive heard of head lift or something like that from the compression. Is it possible that Im experiencing something like that while driving the car? Thus causing the leak to be bigger after I get home?

Oh and here are the pics of the sludge starting to form on the valve cover on the passengers side. This is nothing like last time. It was a good 1/8" thick on the top of the cover.

View attachment IMG_20150527_191050531.jpg
View attachment IMG_20150527_191104016.jpg
 
Sorry to sat looks exactly like mine when i cracked my head as described. Looks like a twin. MT
 
Well, I can always pull the head and see if I can find/see something. Is there any reason to pull both heads? I picked up 2 gaskets just in case. So where exactly did your head crack at MT?
 
let me get picture for you, if I can. But right above the area that you are showing, leaks onto the same pad, and then onto k frame. Heads are still in car but I pored 2 bottles of head gasket repair, to good effect. I have a set of 302, 714 heads going in soon because of my stupid mistake. MT
 
Hit the entire area with contact cleaner, clean it real good.

Get a can of desnex and spray EVERYWHERE along the front and side of the engine in the area, intake, head, block. Repressurize the system and see where the leak originates.
 
I pulled heads twice thinking I had bad head gaskets. NOT. I cracked both my heads in the same place, the same way. MT
 
crackedback said:
Hit the entire area with contact cleaner, clean it real good.

Get a can of desnex and spray EVERYWHERE along the front and side of the engine in the area, intake, head, block. Repressurize the system and see where the leak originates.
Click to expand...

I thought I had it pretty clean but I can clean it again. Me and the wife sat there looking at the engine, trying to find the leak. I was under neath and she was up top. We could only see the puddle form but not where it was coming from.

Ill re clean it tomorrow and try again.
 
right by the head bolt going down on angle was where mine was/is both sides. It was very hard to find and I was in denial, but I did find it eventually. NOT saying that IS what you have, just a thought. MT
 
Have you checked the oil level on the dip stick since you pressurized the system to make sure you don't have a water leak to the inside? Make sure the level is not increasing on the stick.
 
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