Intake coolant leak

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There is definitely a little gap from the intake to head surface with no gaskets
 
Freezerman said:
There is definitely a little gap from the intake to head surface with no gaskets
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You’d be surprised that that will seal. Probably not with an .028 gasket though.

Set the intake back on without the carb and look and see how the ports line up.

I’m betting with no gasket the intake ports are lined up or slightly low.
 
For some reason the water ports don't quite seal at the bottom edge, not sure that the gaskets get compressed along the bottom well. If I change the head gaskets from .028 to more like .040 would that improve the mating angle?
 
Newbomb Turk said:
It’s doubtful you have two different intakes that won’t seal.

Make damn sure the manifold isn’t sitting on the china walls.

I’m not sure why .028 gaskets. That’s pretty thin and usually has limited use. I used thin gaskets like that when I needed a thinker gasket and couldn’t get one. That’s basically a .030 gasket and I’d stick that with a .045 or .060 to get **** lined up.

When the manifold is sitting on the heads with NO gasket it shouldn’t be touching the china walls and the bolt holes in the manifold should NOT be lined up.

The holes in the intake should be lower than the bolt hole in the head.

If the holes line up perfectly with no gasket you need to machine the intake manifold face the thickness of the gasket plus .010.

If you can’t see the hole in the head because the hole in the manifold is too low then you need way thicker gaskets.

If you have to machine the intake make sure you have enough room between the intake and china walls so that when you machine the manifold it doesn’t end up on the china walls.
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the ports will be misaligned with no gaskets but the bolt holes will be lined up fine. remember magnum's have vertical bolts so even if you lift the intake up a foot then 13" bolts would still drop down through and line up (extreme but you get the idea). :lol:
neil.
 
Yes, I did. When I removed the intake and looked at the gaskets it appeared the bottom edge didn't get crushed well
 
oldkimmer said:
Yes
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mygasser said:
the ports will be misaligned with no gaskets but the bolt holes will be lined up fine. remember magnum's have vertical bolts so even if you lift the intake up a foot then 13" bolts would still drop down through and line up (extreme but you get the idea). :lol:
neil.
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Yeah, I saw that bone headed mistake on my part.

He needs to use whatever gasket thickness he needs to get the ports lined up.

That’s what matters.
 
I would see if intake gaskets made of a softer, more compressible material [ Mr. Gasket? ] are available.
 
Somebody on here had this same issue a while back. It ended up that the intake manifold was machined wrong in the corners and would not seal. Can you get a good picture of the bottom of the intake at the front corners where the intake, heads and block all come together?
 
This is about as good as I could get, had to use a mirror. The gap is the china wall. No gasket installed

20240916_160400.jpg
 
Freezerman said:
This is about as good as I could get, had to use a mirror. The gap is the china wall. No gasket installed

View attachment 1716304231
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With the manifold sitting on there do the ports in the manifold line up with the ports in the head?

You can’t pick a gasket thickness without knowing that. Or you have to pick a gasket and machine the manifold to make it fit.

Whoever told you just drop some .028’s in there was on dope.

That’s pretty thin.
 
I dry fit the gaskets, hadn't tried that yet... have a gap to the heads on both sides. Hughes recommended the .028 gaskets as well as magnumswap.com. maybe these heads are bad? I have used these gaskets with zero problems before..

20240916_161628.jpg
 
How can I check for port alignment when the manifold is in place? The gaskets line up with the manifold ports and the head ports when I check them independently
 
Freezerman said:
How can I check for port alignment when the manifold is in place? The gaskets line up with the manifold ports and the head ports when I check them independently
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Because the thickness of the gasket changes where the manifold sits on the head.

You need to figure out if the manifold is sitting where it should be.

I don’t do much magnum stuff. I look at the relationship between the holes in the intake with the holes in the head. I pick the gasket I want and I machine the manifold to fit if I have to.

If you can’t use the bolt holes because of the sorry way Chrysler made the bolts you need to get a light and look with your eyes into the plenum of the manifold and see how the ports line up.

That will tell you if what you have is right.

Look into the intake and look at where the floor of the manifold meets the head.

With no gasket the manifold floor better be lower than the floor of the port in the head.

If it’s level with the head you will need to machine the manifold the thickness of whatever gasket you pick plus a clean cut.

None of these intakes are very flat. So I take a clean cut. I machine just enough off to get a fresh clean surface and then I remove whatever I need to.

Let’s say with no gaskets your manifold lines up perfect. That means you need to machine the manifold like I said.

If the manifold is higher than the head, you have to take off the thickness of the gasket and then some.

If the manifold is lower than the head you just need thicker gaskets.

You need to figure out if the manifold is even close to fitting before you do anything else.
 
Here's an article from Hughes website about measuring the manifold gap.
 

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  • INTAKE_MANIFOLD_SEALING_DECEMBER_2021.pdf
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Thank you, very interesting. I an going to pull the heads anyway so I will check this
 
I see that you have a mismatch in machining. You're going to have to start from scratch in half either the heads cut which is probably the correct way or the intake. If you bolt up the head to one side of the head and you have different thicknesses from top to bottom on the opposite side then you know you have to do some machining somewhere gaskets won't fix it
 
Why are you pulling the heads? If you place the intake on without gaskets, BOTH sides look like the picture? With it sitting on the china wall? If it were mine, I would put new gaskets in place and set it on. Take a feeler gauge and measure the china wall gap. Then space the china wall up and remove the gaskets and put it back. That will be pretty close to how it will be when assembled. Then measure the top and bottom of the intake and head gap with feeler gauges. Also, if it was peeing water externally, it probably was leaking water internally. Take a quick sample of the oil. See it you get water first.
 
To see what the port match is you can get one of the better bore scopes. Stole those photos……..:):):)

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EF3CDB72-13BD-4316-8A9A-E446CC91541B.jpeg
 
It does leak internally a little as well. Fortunately I have never let it leak long enough to get more coolant inside except for the lifter galley, I will change oil before running.
I did buy a borescope and ran it down the water passage, definitely mismatched inside and pushed gasket up. That's why I think slightly thicker headgaskets will help by giving a little more space at the bottom of the V where the intake and head meet
 
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