Oil on intake???'s

[79 USA 1]

Above you said you sealed the bolts with RTV so I mentioned the other products.

Two ideas, pull some or all the manifold bolts and see if there is oil up at the head level, and with it fully warmed up see if there is pressure in the crankcase maybe one of those cracks is not sealed up and exhaust or compression gases are getting into the crankcase pressurizing it,

Two different posters, same problem.
My 406 (79 USA 1) has the cracked and repaired heads with the same oil pooling issue in the lower pan of the Air Gap manifold.
dickymoore is experiencing the same pooling issue and we both are looking to see if anyone else has had the same problem. If so what was the issue and how did they remedy it.

As I stated I feel the issue with my repaired heads is that they took quite a few passes to true up the head gasket surface after crack repairs on my 882 heads. I've had an issue with the seal at the bottom of the intake gaskets below the ports failing allowing oil into the ports at high vacuum. What is frustrating is not having any witness marks or "oil trails" to show where the leak is coming from. Kind of like when you have a weep hole on a water pump go bad...follow the water trail or a leaking valve cover will have a path below it.

 

[dickeymoore]

What cracks?

 

[565bbchevy]

Yep I used sealant on all the bollts doesn't look like its leaking from the bolts

I would pull out a couple of the center intake bolts and see if it looks like oil is seeping past them if so I would clean the threads and apply an RTV instead of the paste you are using.

 

[dickeymoore]

What type of RTV do you recommend?

 

[565bbchevy]

What type of RTV do you recommend?

I use Permatex Ultra black, others may use something else but this product has always worked well for me.

 

[dickeymoore]

ok

 

[565bbchevy]

Two different posters, same problem.

One poster, one thread hijacker 😉 Did you do any mock ups with the intake on the heads without the intake gaskets to check the clearance and possible angle differences, I feel all of your issues are with those heads, have you tried a thicker intake gasket?

 

[79 USA 1]

One poster, one thread hijacker 😉 Did you do any mock ups with the intake on the heads without the intake gaskets to check the clearance and possible angle differences, I feel all of your issues are with those heads, have you tried a thicker intake gasket?

Point taken...Sorry didn't intend to hijack the thread. 😳
ELCAM seemed to have both lumped together.
As for checking the clearances I'm guilty of not checking. Big part of the reason for replacing them next time it's apart.

 

[565bbchevy]

Point taken...Sorry didn't intend to hijack the thread. 😳
ELCAM seemed to have both lumped together.
As for checking the clearances I'm guilty of not checking. Big part of the reason for replacing them next time it's apart.

I'm just giving you a hard time.
So have you tried a thicker intake gasket? I have seen where people have installed heads that are milled and though everything appears to go together well the intake gaskets don't fully compress to get a good seal, I am assuming you use an RTV for the china wall instead of gaskets also.

 

[dickeymoore]

So whats a thicker intake for sbc i used felpro 1205 intake gaskets?Thanks