intake gasket is sweating coolant?

Phreakish

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Lay the Gasket on a white paper towel over night. See what colors it turns.
I'm wondering if most of the staining is oil, and you happen to have a small coolant weep near the coolant passages.

I'd still seal the bolt threads when you reassemble. Like AJ said, they should be blind, but aluminum castings have a way of seeping through porosity sometimes. It hurts nothing to seal the threads.
If also put a small perimeter application of right stuff around the coolant passages.
 

71DodgeDemon340

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I dealt with some similar problems after going to a six pack manifold and pro Comp heads. gaps the fitting surfaces are close but not perfect . In my opinion the top end will need to be taken down and mating services checked,mocked up , adjustments made top quality gaskets and sealants used reassembled. Good luck.

it shouldnt need to be, it was sealed fine for the first 3 or 4 years after it was rebuilt, after about 3 or 4 years i had a small amount of coolant that would come out of the front pass side bolt but would be one little dab of coolant once every month or so, here the first of this year it had gotten worse which is why i pulled the intake the first time. When i did have that small amount leak i thought the intake bolts went into the water jacket so i pulled that one and put sealant on it, stayed good for a little while but eventually that super small leak came back, ran it for another 2 or 3 years and then this year is when it started leaking worse.
 

Phreakish

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it shouldnt need to be, it was sealed fine for the first 3 or 4 years after it was rebuilt, after about 3 or 4 years i had a small amount of coolant that would come out of the front pass side bolt but would be one little dab of coolant once every month or so, here the first of this year it had gotten worse which is why i pulled the intake the first time. When i did have that small amount leak i thought the intake bolts went into the water jacket so i pulled that one and put sealant on it, stayed good for a little while but eventually that super small leak came back, ran it for another 2 or 3 years and then this year is when it started leaking worse.

Could your intake have a hairline crack?
 

71DodgeDemon340

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Lay the Gasket on a white paper towel over night. See what colors it turns.
I'm wondering if most of the staining is oil, and you happen to have a small coolant weep near the coolant passages.

I'd still seal the bolt threads when you reassemble. Like AJ said, they should be blind, but aluminum castings have a way of seeping through porosity sometimes. It hurts nothing to seal the threads.
If also put a small perimeter application of right stuff around the coolant passages.


i plan to, i used thread sealant on all the bolts when i last did the intake gasket. I also plan on using rtv around the coolant passages instead of gasket sealant
 

71DodgeDemon340

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Could your intake have a hairline crack?

on all 4 corners? I wouldnt think so. Just weird ot was sealed for 2 months then all the sudden appeared, just doesnt make sense, i would think if it was soaking the gasket with oil that the intake would have oil on it as well
 
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Phreakish

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on all 4 corners? I wouldnt think so

That's why I'm wondering if most of the staining isn't oil, and it's only coolant on one?

I'm spitballing for sure, you're the one seeing it first hand, and I'm not questioning what you're seeing, just tossing out some stuff to maybe rule out in case it looks like one thing but is some normal mixed with abnormal?

I've gotten hyper focused on one thing before and turned a mole hill into a mountain - some outside perspective sometimes helps with that.

If it is indeed all coolant at all 4 corners then it's odd. The only way for it to really happen is for a lack of clamping on the Gasket, but like you said - it has an even impression.

Maybe felpro got a bad batch of material? Hard to say.

I'd verify everything is straight and flat with a straight edge and feelers, set the Gasket on a paper towel overnight, and then plan to reassemble with right stuff, thread sealer and ample torque. What else can be done, right?
 

71DodgeDemon340

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That's why I'm wondering if most of the staining isn't oil, and it's only coolant on one?

I'm spitballing for sure, you're the one seeing it first hand, and I'm not questioning what you're seeing, just tossing out some stuff to maybe rule out in case it looks like one thing but is some normal mixed with abnormal?

I've gotten hyper focused on one thing before and turned a mole hill into a mountain - some outside perspective sometimes helps with that.

If it is indeed all coolant at all 4 corners then it's odd. The only way for it to really happen is for a lack of clamping on the Gasket, but like you said - it has an even impression.

Maybe felpro got a bad batch of material? Hard to say.

I'd verify everything is straight and flat with a straight edge and feelers, set the Gasket on a paper towel overnight, and then plan to reassemble with right stuff, thread sealer and ample torque. What else can be done, right?

i cant confirm that all the dampness is from coolant but it was sweating coolant on the four exposed parts of the gasket on the corners that extends past the intake. But would the oil from the valley be seeping through the gasket? I wouldnt think so.
 

71DodgeDemon340

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Also i looked at the intake in correlation to the holes in the head before i pulled the intake. the bottom of the bolt opening on the intake was just about lined up with the bottom of the threads in the head maybe just below, from what ive read this is about ideal as the intake will go down when tightened so the bolt holes will end up about in the center. Ive read what you dont want is if the top of the bolt opening on the intake is aligned with the top of the threads in the head then when you tighten it down it can actually bottom out on the bolt preventing the intake from pulling down completely.
 

RustyRatRod

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the 4 outer threaded holes on the edelbrock heads are blind, they are not exposed to coolant
You need sealant around the end water passages too on both sides of the gasket. I don't see where you put any on.
 

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i cant confirm that all the dampness is from coolant but it was sweating coolant on the four exposed parts of the gasket on the corners that extends past the intake. But would the oil from the valley be seeping through the gasket? I wouldnt think so.

Yes that is mostly oil on that gasket.
 

71DodgeDemon340

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You need sealant around the end water passages too on both sides of the gasket. I don't see where you put any on.

i cant get a consistent instruction on the gaskets. On the instructions for the intake it says to only use gasgacinch on the head and head side of the gasket. On the edelbrock intake gasket instructions it says to use gasgacinch on the head and head side of the gasket and rtv around the coolant passages but only on the intake side.
 

RustyRatRod

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Well, I don't know what else to tell you. You've gotten advice from several members, me included who've built engines that lasted for years with no leaks. I believe I would back up and listen. Good luck with it!
 

RustyRatRod

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i cant get a consistent instruction on the gaskets. On the instructions for the intake it says to only use gasgacinch on the head and head side of the gasket. On the edelbrock intake gasket instructions it says to use gasgacinch on the head and head side of the gasket and rtv around the coolant passages but only on the intake side.
"However" you did it before, didn't last, did it? Just an observation my friend.
 

71DodgeDemon340

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Well, I don't know what else to tell you. You've gotten advice from several members, me included who've built engines that lasted for years with no leaks. I believe I would back up and listen. Good luck with it!

i understand that and i tried to prevent it from leaking.
"However" you did it before, didn't last, did it? Just an observation my friend.

Im guessing the #2 gasket sealant doesnt work well on the intake gasket? I used it on my thermostat and water pump gasket with no problems. I figure it would have on the intake, im going to use rtv this time and we shall see. I know you guys are trying to help but it just doesnt make sense. It was a absurdly small amount of coolant residue coming off of the exposed flaps of the gasket. Also if most of the gasket is darkened from oil I dont see how the oil from the valley would creep up the gasket if its sealed.
 

George Jets

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Clean surfaces, scrub any shinny aluminum surfaces with a Red Scotch Brite pad to rough them up and give the gasket and sealers some tooth to bite into and hold.

Final clean all surfaces with brake parts cleaner and a clean wrag, Not alcohol.

Clean bolt threads with brake parts cleaner before applying the Aviation sealer.
 

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I don't doubt you did all things right but leaks sometimes happen. But it's been my experience once they develop resealing them without reassembly is seldom achieved. At least not 100% or for very long.
 

71DodgeDemon340

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Also not sure if will make a difference but the edelbrock gaskets are .060 thick and the felpro steel core gaskets are .065 thick. The original gaskets that were in there from the rebuild appeared to be about the same thickness as both the edelbrock and felpro gaskets.
 

AJ/FormS

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Just saying, the taste of antifreeze is unmistakably sweet.
Jus asking, were the decks shaved?

I took a bunch off my decks and the job was crap; on the one side, the surface went downhill towards the firewall. On the other it was downhill to the rad. And neither side was 90* to the other. So when brand new Edelbrocks went on and a used iron intake, she sucked air everywhere.
I reasoned that an alloy intake might twist into working for the rest of the summer, and it did. But the following winter I took the engine out and had a different shop straighten it out and then installed a new AirGap, problem solved.
 
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Phreakish

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i cant confirm that all the dampness is from coolant but it was sweating coolant on the four exposed parts of the gasket on the corners that extends past the intake. But would the oil from the valley be seeping through the gasket? I wouldnt think so.

That's why I'd lay the old Gasket on a paper towel. Should help you determine oil vs coolant.

I wouldn't expect much oil in the Gasket. But I also wouldn't expect coolant, or the leak you had.. Which is why a bit more info might shed some light.

Gaskacinch is great for reusing gaskets and holding them in place for assembly. But I wouldn't trust it for coolant sealing.
I also wouldn't trust just one surface being sealed with rtv or other goop. All mating surfaces need it unless sealed with a properly designed oring and groove arrangement. Doesn't take much goop, but it should be on the Gasket (both sides), head, and intake IMO. Otherwise pressure and heat will eventually cause a leak.
 

RustyRatRod

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That's why I'd lay the old Gasket on a paper towel. Should help you determine oil vs coolant.

I wouldn't expect much oil in the Gasket. But I also wouldn't expect coolant, or the leak you had.. Which is why a bit more info might shed some light.

Gaskacinch is great for reusing gaskets and holding them in place for assembly. But I wouldn't trust it for coolant sealing.
I also wouldn't trust just one surface being sealed with rtv or other goop. All mating surfaces need it unless sealed with a properly designed oring and groove arrangement. Doesn't take much goop, but it should be on the Gasket (both sides), head, and intake IMO. Otherwise pressure and heat will eventually cause a leak.
Well that depends. If he didn't put sealer on the intake bolts, engine oil will migrate up the threads. I think even on aftermarket aluminum heads that all but the end bolt holes go into the inside valve cover area. Even if they're not "supposed" to, there's no guarantee the bolt holes are not porous in those areas.....but I think they go all the way through.
 

Phreakish

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Well that depends. If he didn't put sealer on the intake bolts, engine oil will migrate up the threads. I think even on aftermarket aluminum heads that all but the end bolt holes go into the inside valve cover area. Even if they're not "supposed" to, there's no guarantee the bolt holes are not porous in those areas.....but I think they go all the way through.

True. I think my iron heads went through, and I definitely had oil seep up the threads when I used rtv on them. My tf heads go in blind. I even had to grind the bolts I had in order to tighten it all down. The ones I had on hand (12pt arp) were just long enough that it looked tight, but wasn't. Didn't realize it until I got to the end bolts where the manifold flange was thinner.

I have no idea what the bolt situation is like on the Eddie's, but like you said - there's no accounting for possible porosity.

The eveness of whatever is on the Gasket definitely looks like there's something present at every bolt hole..
 

71DodgeDemon340

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So what yall are saying is that possibly oil made its way up through the bolts and soaked the gasket? Only thing on the bolts when i took them out was thread sealant.
 
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