Persistent oil leak from somewhere?

[Fran Blacker]

That sucks! Putting intakes on with the engine in the car is one of my least favorite jobs, especially with a cast iron intake - leaning over the fenders, trying to get it to sit right without disturbing the gaskets/RTV you've spent so much time positioning carefully,...
My only advice is if you've been doing this on your own, enlist the help of someone who knows what their way around an engine to help with the lifting, and perhaps instead of using all studs/nuts, which as you said may be interfering with how the manifold is sitting, have just a couple to keep the gaskets in place while you lower it on, and then use bolts for the rest?

It's allemoanum.

 

[AR67GTX]

Actually handling the intake is not too bad but I did manage to strain a back muscle at some point a little. I had 5 dowels in place (Mancini owes me a 6th one that’s in the mail) so once the manifold hits those it drops straight down. I probably test fit it 4 or 5 times before the final drop. I haven't found an affordable small dowel puller so the dowels are still in and that‘s probably my biggest problem. That and with the manifold sitting loose on the side gaskets, the china wall gap is .130”+ in width - pretty wide. I tried to run about a 5/16 to 3/8” bead of RTV but working around the dowels was a pain. I had some extrusion out the front for about 2/3rd of the width but apparently it didn’t fill completely around the dowels as I had some spitting of fine oil mist appearing up and out of one of the intake dowel pin holes. I think what I may have to try is in addition to the bead of RTV on the block, to also run a smaller bead on the intake front and rear too, and partly fill the dowel holes and then drop the manifold in place.

As soon as I saw it leaking I shut it off and backed all the intake bolts off. I’ll have to separate the RTV but maybe it will lift off the Superformance gasket OK. If not, I ordered another one.

Ain't HotRodding fun?

 

[Fran Blacker]

Could you use two piece sheet metal with 90* bend front and back of manifold to shield the china wall from splashing oil. You can use the splash shield on manifold to clamp the sheet metal shields.

 

[AR67GTX]

You know Fran, I’ve been thinking about that very thing. It would be real easy to bend and trim a couple sheet metal plates to fold over and extend down about two inchs below the china wall on each end, bolted to the heat shield,to cut down on splashing oil getting to the joint. I think after you also mentioning it too, that I’ll look into doing so.

 

[Fran Blacker]

Yes that's what I was suggesting. I would slide the shields under factory splash shied. If you could and get clamping power from factory shield.
On my motor with crossram the copper head gaskets go up to the chinawall all the way across valley. I took a piece of sheet metal with tabs to hook on head gaskets.

 

[AR67GTX]

Interesting observation. When I cut into the RTV on the front with a knife it came out slimed and smeared in some places with some incompletely cured Ultra Grey RTV. This was over 48 hours after I installed the intake. I waited about 26 - 28 hours before starting the car but now I wonder if that was too soon. Wasn’t expecting this.

 

[AR67GTX]

Well, this is the shits! Pulled the intake off and the Ultra Gray on the interior is just as fresh as when I squeezed it out of the tube. It was only set around the sides and maybe a very thin film on the metal. This stuff was about 52 - 54 hours old at the time of these pictures.

So, not sure what to try next but it won’t be Ultra Grey. I have some The Right Stuff but this experience makes me leery of RTV. I may go back to gaskets but it would take about a .18” thick gasket to seal up with 30 to 40% compression. Maybe I need to go with .030“ side gaskets instead of .062”?

 

[dadsbee]

Once it skins on both sides, it's like it's still back safe and sound in it's tube....

 

[AR67GTX]

I let the stuff set for an hour on the manifold before I cleaned it off. It didn’t even skin over in that length of time. New tube bought on line, but has a date code of 2H. Could be 2002, 2012 or 2022.

So. . back to the Fel Pro gaskets with end wall gaskets????

 

[ckessel]

Looks like it was a bad batch. I watched a vid on the Tube where a guy did, essentially, a shootout between different brands and grades of sealers. The OE stuff from the mothership was about the best.

 

[dvw]

Cut apart any RTV and see what it looks like after a day. Ultra grey always stays soft inside for awhile. Doesn't mean it doesn't seal. I've run stuff the next day with ZERO failures. Been using it exclusively for the last 10 years. My racecar has the motor plate/block /water pump along with the split upper intake sealed with it. No gasket, just sealer. None of the stuff I've worked on leaks a drop. Does this look like an engine that leaks?
Doug

 

[AR67GTX]

Yes that's what I was suggesting. I would slide the shields under factory splash shied. If you could and get clamping power from factory shield.
On my motor with crossram the copper head gaskets go up to the chinawall all the way across valley. I took a piece of sheet metal with tabs to hook on head gaskets.

What do you think Fran? They will hang down 2”. Another benefit, if I go back with RTV it will form a backup to the joint to keep RTV in the joint.

 

[Fran Blacker]

Looked at front china wall on my 66 Sat, gasket is hardly compressed. Block never decked .021 head gasket and no more than .010 off heads 1/16" intake gasket. You have that odd splash shield I forgot about that.

 

[AR67GTX]

It’s a repaired splash shield. A center piece was broken out somehow and they riveted a piece of aluminum sheet over the bottom. Repros seem to be out of stock and this one, while different, is serviceable.