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Discussion Starter · #1 ·
My friend and I just completed a 4bbl swap on his 351m and got it running. For the most part we have the carb tuned and the timing is set. The only problem were having is the right bank (drivers side) is puffing bluish smoke from the exhaust. The truck has duals all the way back and no crossovers. Also it never puffed any kind of smoke at all before the 4bbl so that leads me to believe the stem seals and rings/cylinders are fine. Any clue what would cause this, and/or if it will go away over time?

Again thanks to everyone on here that has helped us get through some of the problems we ran into. Any more help will be greatly appriciated.
 

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Discussion Starter · #6 ·
maybe intake gasket is not sealing?
We'll check and see if there are any leaks with some butane

Either that or if the truck sat for a while, you could have had the valve stem seals dry up and are letting oil pass ino the cylinders.
The truck was driven up until the day we tore into it, then we parked it two weeks ago to do the 4bbl swap. Now today its puffing smoke.
 

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Did you use gaskets or the metal valley pan?

I stopped using the gaskets after one of the port gaskets broke on the bottom and started sucking oil from the lifter valley. The same could have happened to you.
 

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We used a Fel Pro vally pan and rtv on both sides. Also used rtv on the front and back rubber gaskets.
I would hate to be the next person to take that intake off. RTV should have only been used on the front and back of the intake.. you put RTV on the rubber gaskets too??? should not do that.. use one or the other not both.. but for the oil usage.. look into the PCV valve. i have seen them suck alot of oil.
 

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I would hate to be the next person to take that intake off. RTV should have only been used on the front and back of the intake.. you put RTV on the rubber gaskets too??? should not do that.. use one or the other not both.. but for the oil usage.. look into the PCV valve. i have seen them suck alot of oil.

Should RTV be used on any gaskets, like cork or the cork/rubber?
 

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on diff covers i use only RTV without a gasket.. only place i use RTV on a motor with a gasket is the waterpump (only because it leaked with gaskets alone) than i use it on the front and back of the intake, other than that i just use the gaskets..
 

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Well my valve covers leaked to I got new rubber gaskets and valve covers and put RTV (blue) where the gasket meets the valve cover and no leaks. I then did my tranny pan with a cork/rubber gasket and no rtv and it still leaks! So I guess Ill have to pull the pan back off and add some RTV. Do you put it on the pan or the tranny or both? What is the difference on the copper RTV?
 

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Discussion Starter · #18 ·
I generally like to smear a thin layer of rtv around the intake ports and "S" rubber gaskets when putting any intake back on. The way I see it, is the rtv fills out any imperfections in the gasket or intake mating surface. I would rather have it hard to come off than for it to leak and have to do it again.
 
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