intake gasket is sweating coolant?

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71DodgeDemon340

71DodgeDemon340

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Hey everyone i recently did my intake gasket around the middle of march and so far havent had any leaks, its been a few weeks since i last ran the engine because ive been busy and tonight i noticed the intake gasket appeared to be wicking coolant on all four corners but only on the exposed part of the gasket that lays against the head, you could barely see some green along the intake only on the top side and a few tiny little specs of what seemed to be coolant, these spots were tiny and there was only a few on two of the corners. again no major drips or significant amount, you almost couldnt see it without a flashlight, just barely enough to moisten the tip of your finger but not enough to wet it, heads, china walls and intake were cleaned thoroughly and wiped with alcohol, i used some permatex #2 around the water jackets on both sides of the gasket and rtv on the china walls. i have no way of getting a torque wrench on most of the bolts but i did tighten in the proper sequence and went over them gradually about 6 or 7 times to ensure they were tightened evenly. I ran the engine 3 or 4 times to confirm there were no leaks but only recently 2 or 3 weeks ago took it on its first drive since i got it back together, it slipped my mind to retorque the intake bolts after a few heat cycles, i checked them tonight and i got a few to move maybe 1/8 of a turn and the rest did move but barely, i was using a 3/8 wrench and was putting a pretty good amount of force on it but i deff dont want to break bolts off especially with it being threaded in aluminum. Im just kinda bummed, i really dont want to have to pull the intake again. I wiped the gasket off to make sure it was dry after i checked the torque and will check it tomorrow, should i only be checking the torque with the engine cold or hot?


You can see how far the gasket is wicking. there was only a hint of coolant at the 4 corners, where it is here it is not wet at all, doesnt really feel damp but you can see where the gasket is darker. Valve cover doesnt seem to be seeping at all. Looks like this on the other side as well. There is no sign of coolant at all on the vertical areas on the head or intake

FF09DD30-3145-4BCC-B1F9-75EE7FED19E2.jpeg
 
That picture looks like the manifold is clamping on the valve cover? Could be an optical delusion, but it looks suspicious.

I'd pull the covers and retorque the manifold and see if you get any more movement from the bolts.

Then I'd grind the valve cover flange a tad just to be sure the covers don't leak after..
 
Phreakish said:
That picture looks like the manifold is clamping on the valve cover? Could be an optical delusion, but it looks suspicious.

I'd pull the covers and retorque the manifold and see if you get any more movement from the bolts.

Then I'd grind the valve cover flange a tad just to be sure the covers don't leak after..
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I agree with this assessment. The intake manifold is on top of the valve cover there and likely on all four corners. Also, #2 is really more suited to seal oil and not coolant. I prefer to use the RTV for coolant. But I don't think that's your real problem seeing the valve cover under the intake manifold.
 
Phreakish said:
That picture looks like the manifold is clamping on the valve cover? Could be an optical delusion, but it looks suspicious.

I'd pull the covers and retorque the manifold and see if you get any more movement from the bolts.

Then I'd grind the valve cover flange a tad just to be sure the covers don't leak after..
Click to expand...

thats the thing the valve covers dont appear to be leaking, i will double check but im pretty sure there is clearance between the valve cover and intake
 
71DodgeDemon340 said:
thats the thing the valve covers dont appear to be leaking, i will double check but im pretty sure there is clearance between the valve cover and intake
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If the intake is clamping on the valve cover flange, I wouldn't expect the cover to leak. But the manifold could.

If you fix the valve cover being under the intake (assuming it is), then the covers might leak when reinstalled.

In any case, double checking there is a good idea. I'd want more clearance than you have shown anyway.
 
RustyRatRod said:
I agree with this assessment. The intake manifold is on top of the valve cover there and likely on all four corners. Also, #2 is really more suited to seal oil and not coolant. I prefer to use the RTV for coolant. But I don't think that's your real problem seeing the valve cover under the intake manifold.
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the intake was installed and tightened with the valve covers loose and out of the way. Theres no way the valve covers are under the intake.
 
71DodgeDemon340 said:
the intake was installed and tightened with the valve covers loose and out of the way. Theres no way the valve covers are under the intake.
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That picture surely suggests otherwise. Maybe the edge of the valve covers is just wedged under that lip of the intake.....but it IS under it. Regardless, it sounds like you're going to have to remove the intake anyway.
 
71DodgeDemon340 said:
the intake was installed and tightened with the valve covers loose and out of the way. Theres no way the valve covers are under the intake.
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And you made sure there were no dowel pins in the China wall, right? Is it just RTV on the China wall, or a Gasket too? Cork?

Just asking so the basics are out of the way.

What heads do you have? I'm running the tfs heads and with a standard 3/8 wrench I've determined I cannot strip the threads in them, LOL.

Did you dry fit the manifold before install and do some checks with a feeler at the head interface?

If it's weeping to the outside, I'd be worried how much is going inside. Typically the Gasket won't weep on-end, what you're seeing is migration of the glycol through a gap which then wets the Gasket surface as things evaporate. Might be worth tapping on choice areas of the manifold with a soft face hammer and then retorquing the bolts around the water passages. I'd look up the factory torque for those specific bolts and use that as an upper limit.
 
RustyRatRod said:
That picture surely suggests otherwise. Maybe the edge of the valve covers is just wedged under that lip of the intake.....but it IS under it. Regardless, it sounds like you're going to have to remove the intake anyway.
Click to expand...

It's also possible he did exactly as stated, but the cover wedged in there and upset something. Those bolts are such a PITA to tighten.. I have a handful of spare wrenches I bent, cut, and ground to help R&R manifolds and I still hate it!
 
Phreakish said:
And you made sure there were no dowel pins in the China wall, right? Is it just RTV on the China wall, or a Gasket too? Cork?

Just asking so the basics are out of the way.

What heads do you have? I'm running the tfs heads and with a standard 3/8 wrench I've determined I cannot strip the threads in them, LOL.

Did you dry fit the manifold before install and do some checks with a feeler at the head interface?

If it's weeping to the outside, I'd be worried how much is going inside. Typically the Gasket won't weep on-end, what you're seeing is migration of the glycol through a gap which then wets the Gasket surface as things evaporate. Might be worth tapping on choice areas of the manifold with a soft face hammer and then retorquing the bolts around the water passages. I'd look up the factory torque for those specific bolts and use that as an upper limit.
Click to expand...

correct no dowl pins on the china walls and used rtv to seal them. Im running the edelbrock performer rpm heads. Didnt dry fit the manifold. Everything looked to be good but did not run a straight edge along the china walls or heads or intake. All corners were sealed before just had coolant leaking from the pass side front intake bolt which is why i changed the gaskets.
 
71DodgeDemon340 said:
correct no dowl pins on the china walls and used rtv to seal them. Im running the edelbrock performer rpm heads. Didnt dry fit the manifold. Everything looked to be good but did not run a straight edge along the china walls or heads or intake. All corners were sealed before just had coolant leaking from the pass side front intake bolt which is why i changed the gaskets.
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Oh! What did you use to seal the bolts? Not sure if the manifold bolts go into water or not, but if so you might need some plumber's dope on them. I seem to remember suffering a leaky bolt once too, and that was my solution. Can't remember if it was the manifold or a water pump bolt, but it leaked twice after trying to seal with RTV. The pipe dope fixed it good.
 
Phreakish said:
It's also possible he did exactly as stated, but the cover wedged in there and upset something. Those bolts are such a PITA to tighten.. I have a handful of spare wrenches I bent, cut, and ground to help R&R manifolds and I still hate it!
Click to expand...

i will double check the clearance of the valve covers, but i moved them back, installed the intake, then tightened it. I loosely set the valve covers back on and took them back off the next day to replace the valve cover gaskets.
 
Phreakish said:
Oh! What did you use to seal the bolts? Not sure if the manifold bolts go into water or not, but if so you might need some plumber's dope on them. I seem to remember suffering a leaky bolt once too, and that was my solution. Can't remember if it was the manifold or a water pump bolt, but it leaked twice after trying to seal with RTV. The pipe dope fixed it good.
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Yeah when i had that bolt originally leak years ago i thought that too but the 4 corner bolts into the head are blind near the water jacket. They are not into the water jacket
 
Phreakish said:
It's also possible he did exactly as stated, but the cover wedged in there and upset something. Those bolts are such a PITA to tighten.. I have a handful of spare wrenches I bent, cut, and ground to help R&R manifolds and I still hate it!
Click to expand...
That's kinda what I was referring to in my second reply.
 
71DodgeDemon340 said:
Yeah when i had that bolt originally leak years ago i thought that too but the 4 corner bolts into the head are blind near the water jacket. They are not into the water jacket
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Bummer. Sounds like Rusty is right, and the manifold probably needs to come back off. Sounds like it needs more schmoo.
 
71DodgeDemon340 said:
Do you guys check the torque with the engine hot or cold? Or does it matter?
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Both, just in case.
My last manifold swap, I torqued it and then retightened when I got it back in the barn after a rip around the block.
No torque wrench here either, just lots of grunting on short wrenches and wobble sockets where they fit.
 
Being a minor pain in the butt?

Here you go "pain in the butt reliever"

Have used this to seal up minor coolant leaks on all kinds of vehicles and farm equipment. Works

Screenshot_20220519-014148_Firefox.jpg


20220519_015000.jpg

1/2 pint will seal it up.
 
Won't hurt a thing to retorque everything again after several heat cycles. Since you're havin trouble with it, that's what I'd do. Do it cold first, then hot, then cold again. Caint hurt.
 
Checked it this morning, no sign of coolant, went back over the bolts again and got all of them except for one to turn maybe a 1/16th of a turn
 
Welp i guess im gonna end up pulling the intake again, came home today and all for corners has a light film of coolant coming out of the gasket, i dont understand how this is happening, didnt have this issue before, it was only leaking to the one intake bolt but never wicking out of the gasket. Ill try checking the torque one more time while its hot and see. Its just aggravating, i was careful and tedious when replacing the gasket, making sure everything was clean and put gasket sealer and rtv in the right spots. Unless its a bad set of gaskets im not sure, they are felpro so youd think they would be good quality. They are even thicker at .065 than the edelbrock gasket which is .060
 
For the hell of it I left the radiator cap loose and will observe it over the next day, the radiator is full as i have a overflow tank but im wondering if just a fluctuation in the ambient temp is causing the coolant to expand and push out of the gaskets, i dont think that will make a difference since i would think there is more pressure on the system while its running but im just curious.
 
Just a thought the Felpro gasket may be designed for Iron heads to and Iron Intake, factory applications.

Edelbrock Gaskets more than likely designed to seal the Aluminum surfaces, aftermarket applications.
 
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