I recently changed my intake on a 350 tbi. Now i have an oil leak. The truck can stand all day at idle and no leak. As soon as i drive it it leaks when i park. It only leaks under load. I checked the oil pressure sending unit that screws into the back of the block and it was fine. I think maybe i didnt put enough rtv gasket silicone on the back of the intake and block mounting surface. What do you guys think... Any help will be appreciated

 

I think you answered your own question.

 

takes less than 1/4" bead of rtv to have enough to make a seal. if you think that's the problem fix it and see if the leak goes away

 

Yup, I'd start there as far as guessing.....

Or, rather than guessing, take the car to the quarter car wash, and sterilize the motor; then drive it for a couple of minutes; and stop and get out and look at it and see where there's fresh oil.

 

Sounds like the china wall to me. Mine used to do the same thing. I pulled the intake and resealed the china wall and the leak stopped. I think thats probably your problem as well.

 

china wall?

 

The two small gaskets that go on each end of the intake are called china wall gaskets. Thats what those two openings are referred as, china walls. Some people use the gaskets and some dont. I am one who doesnt. Just gotta make sure you use enough RTV.

 

I just use RTV also. Always works for me.

 

Isnt there that little cirlce gasket around the base of the dizzy, too?

 

yes...

 

first time i took it out, it didnt even have one on there. maybe it fell off when i pulled it out, cause it's never leaked..