Technical Intake Manifold Gasket keeps leaking coolant - wrong gasket?

All
I am at my wits end, and I am hoping someone can enlighten me on this - or point out what I am missing.
Here is my situation - I am finishing up a project, its a 350 sbc
block casting number 14093638
heads are iron 462624
I am putting - or trying to put on - an offenhauser tri power manifold I got from vintage speed
The problem is is that it continuously leaks coolant. It will leak at then ends by the runners, it will leak out the intake bolt holes, and will leak into the oil. Long story short I am not getting any type of seal. I pulled it off three times an reinstalled - using rtv, not using rtv, I am at a loss - nothing works.
Am I doing something wrong? Do I need a different gasket or something? Any help would be greatly appreciated - this is the last thing I need to finish up before I am able to actually drive my coupe.
Thanks in advance.
Ron

 

Are you:

a. Torqueing the bolts in sequence and at the proper ft.lbs.?
b. If you're using the manufacturers end gaskets, toss them and get "The Right Stuff" (best RTV ever) to replace the end gaskets.
c. Are the gaskets the right gaskets?

 

Thanks for the reply
- yeah, I am torqueing in sequence
- first time I used the end gaskets, second and third time I used rtv
- it sure looks like the right one - everything lines up

do you think there could be a thicker gasket? Have you ever used rtv to line the coolant ports on top of the gasket? - I have never had to do that before
thoughts?

 

put sealant on the manifold bolts that go into the water p***ages

 

I'm interested in the Intake Manifold. Early intakes and heads were compatible (IE pre '57 or '58) Your 462624 heads have small runners but are absolutely huge compared to 265 heads and intakes. If you put an older intake designed for a 265 or early 283 it will bolt up but not work. Not seal at least.

I apologize if this is too basic but I suggest holding the gasket (dry of course) against the heads and look for mis-matches. Do the same with the intake.

I totally agree with tfeverfred. Use a good RTV and pitch the end gaskets. I use sealant on the bolts too as they go in the water jackets. Using RTV on the coolant ports is a good idea too.

 

Clean all the gasket surfaces and set the intake on with no gaskets.
Use feeler gauges and also a flashlight to see if all of the mating sufaces match up
It is possible that your your heads, the block decks or the intake has been surface ground and causing the intake to not fit properly.

 

What intake manifold gaskets are you using? The ones that come in the gasket sets usually are for iron manifolds. They sell a slightly more malleable gasket for aluminum manifolds