3 replies to this topic

[LXCHEV]

Would love some advice here....

 

About to drop the intake manifold back onto a 304 V8. Project car. Came with brand new intake gaskets (unknown brand) - as pictured below.

 

Questions:

 

1. The bulges/raised seals around the intake ports, are different around the water ports (they only go half way around). If you visualise them going all the way around, it seems they'd hit the bolt holes, so this seems quite intentional to me. Thoughts? Looking online, other brands of gaskets have full seals... so I'm just wary....

 

2. Assuming I use these (which I'd like to) - should I add a thin smear of gasket goo (ultra blue/grey/black etc) around the water ports for added security? Or would you trust them bone dry?

 

3. Why are the rear water ports blocked off on these gaskets? There are water ports in the heads, and in the intake manifold.

 

I have also found a seller on ebay, listing Brand New Old Stock GM gaskets - which look identical to these ones of mine. The partial bulges around the water ports, and also the blocked off rear ports. So I'm assuming this is indeed factory spec?

 

 304 Intake Gaskets 1.jpg   183.36K   2 downloads

 

 304 Intake Gaskets 2.jpg   130.14K   2 downloads

 

 304 Intake Gaskets 3.jpg   152.48K   2 downloads

 

And lucky last - here is the ebay one I found for the NOS GM ones:

 

 304 Intake Gaskets - GMH NOS.JPG   64.48K   2 downloads

Edited by LXCHEV, 28 June 2023 - 04:35 PM.

[rexy]

I suspect the water port arrangement is so any leak is preferentially directed to the outside world rather than the valley.

 

I have always used a little permatex 3 (the old Aviation form a gasket) but I notice Dandy engines used a small amount of silicone around the water ports on my BBC.

[LXCHEV]

Thanks rexy. I'm going to use a very conservative amount of whichever gasket goo I have in the box of parts - just around those water ports.

 

I had a closer look at the intake manifold rear water ports and realised they don't go anywhere, so that explains why the gaskets are blocked off at the rear at least.

[ozyozyozy]

Little gasket goo(grey, blue) around the coolant port and it will be fine. The genuine style of gaskets are the better ones to use.