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Discussion Starter #1
I bought a performer intake manifold from a fellow car guy/reservist from my reserve center recently and have some issues. We installed the intake while the engine was on the stand and everything was torqued properly a couple weeks ago. Fast forward to today, the engine/tranny had been reinstalled, and we did the last minute hookups, vacuum lines, fuel line, plugs, wires, etc.
We went to put water into the radiator for intial fire up attempt, and it came running out the back of the engine. Found that it was leaking from the intake manifold, so we checked the bolts and they were loose! So we went around and hand tightened all the manifold bolts. The radiator held water level and the leak seemed to disappear. Check the oil level on dipstick and it reads high and shows some water had entered the cylinder. Removed spark plugs 1 at a time and when I got to cylinder 7, water drained out of the spark plug hole. So I bumped the engine a couple times to force out any remaining water in cylinder 7. After getting any excess water out of the cylinder, opened the oil drain plug to drain out water in bottom of pan until oil started to drain and recapped pan. Finally got the engine to crank over and start, but noticed water started bubbling and forming in the pockets on top of the intake manifold, it appeared to stop leaking when the engine finally warmed up. We were thinking maybe after the engine cooled down we'd go back around and retorque all the intake manifold bolts to help cure the leak. Anybody else encounter issue like this? A friend suggested using a thicker intake gasket if the retorquing of the bolts doesn't work. Hoping this is an easy fix.
 

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I always put a thin layer of silicone around the water jacket and intake ports on the head side, set the gaskets and manifold inplace and install a couple of bolts snug, after a couple of hours remove intake and make sure gasket did not move. Now put another thin layer of silicone on the intake side and torque down.
 

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Are you sure the heads and/or manifold has not been cut or milled?

This happened with my old 283, water everywhere. Took the whole thing apart, got real lucky meeting the nicest machinist in the world, brought him my heads and intake and he immediately noticed my heads were angle milled, so he cut the intake to match, no probs. We've been good friends now for 20+ years.
 

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Discussion Starter #4
Are you sure the heads and/or manifold has not been cut or milled?

This happened with my old 283, water everywhere. Took the whole thing apart, got real lucky meeting the nicest machinist in the world, brought him my heads and intake and he immediately noticed my heads were angle milled, so he cut the intake to match, no probs. We've been good friends now for 20+ years.
hmmm... I honestly dont know. I bought the heads from a friend of mine, they are cast iron 400sbc heads I put on my 350sbc. I think they had been decked to compensate for thicker head gasket, but I don't believe anything else was done to them. I'll have to find out from him.
 

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from my experience with edelbrock intakes once you initialy torque them down once. i have to torqu them atlest once or twice more after the engine has run for awhile.
l would be interested to find out tho. your heads have been milled and you are using a stock headgaskit the alignment would be off by afew mm's.:confused:
 

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I would ask him and also try to track down some stock dimension profiles and do some comparing yourself. I understand a few mm's may be tough to spot. How bout the appearance of the intake where it sits on the heads....maybe a look to see if it appears stock or some swirly cut marks.

I m not saying your intake is cut, don't want to cause alarm here. Maybe its a simple solution, like retorquing or a good silicone installation. Just mentioning it cause I learned the hard way.
 

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Discussion Starter #7
Well, it sounds like the only issue with the manifold is the initial bolts that were loose. After tightening them up, the manifold did leak around the bolt holes until the engine got hot and I think the gasket sealed up. When the engine was hot, it wasn't puddling any more water and seemed to settle down. Today, my dad called me and told me he went around and checked all the intake bolts, found a couple that needs a couple turns on them and fired up the engine. He said that he only needed to add just a small amount of water to the radiator, and that there was no more oil or water leaking out of the intake which makes me feel a whole lot better. Now I just need to get my carb rebuilt and I should be good to go.
 
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