Fuel Running Rich, White smoke
- Thread starter Tas_Jak
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Uh... I'll let engine guys confirm but I suspect through the piston rings.
So the PCV system needs to be a closed system so no valve cover breathers.
I 100% agree with Noobz that you need to perform a compression test then a leak down test to see what you are dealing with. If it’s any kind of healthy then you will have to get the PCV system back to a closed system.
The plate that Noobz referred is on the right end of this lower:
I 100% agree with Noobz that you need to perform a compression test then a leak down test to see what you are dealing with. If it’s any kind of healthy then you will have to get the PCV system back to a closed system.
The plate that Noobz referred is on the right end of this lower:
Pic when I first picked it up a bit ago.
Will do the compression test today, I know I tested cylinder one and got like 150 if I remember.
So the PCV system needs to be a closed system so no valve cover breathers.
I 100% agree with Noobz that you need to perform a compression test then a leak down test to see what you are dealing with. If it’s any kind of healthy then you will have to get the PCV system back to a closed system.
The plate that Noobz referred is on the right end of this lower:
Sorry, what was Noobz referring to when he mentioned this plate, I looked back at the messages and still don't understand.
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Odd setup, modified gt40 tubular intake, 19lb injectors, accessories deleted in a drag car which probably couldn't have been much quicker than low 13's unless they used nitrous. Also the heads look to be painted iron heads.
I can't tell the size of the TB or if it's stock in the pics, but there is no EGR spacer and the vacuum line has a bolt in it.
Then you have what appears to be an aftermarket fuel system with rails.
Not much of it makes sense, other than the idea that they slapped a bunch of parts back on it to sell it.
I can't tell the size of the TB or if it's stock in the pics, but there is no EGR spacer and the vacuum line has a bolt in it.
Then you have what appears to be an aftermarket fuel system with rails.
Not much of it makes sense, other than the idea that they slapped a bunch of parts back on it to sell it.
The plate he is referring to is a oil splash baffle, early intakes had a weeny little plate that was riveted to the bottom of the lower intake right under the PCV hole, I'll post a pic from the 'big screen' later, it basically keeps oil from being sucked up into the intake, sometimes, well as time and miles went by it was discovered as the oily crude gathered on the screen under the PCV, oil residue would traveled up the crudey screen and get sucked up into the intake so they put a longer baffle under there, like the one in the pic.
Only has this little one on the intake
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That's the weeny one, it's good and works just fine on the street and most builds, just have to replace that screen under the PCV valve every 100k miles or so.
At least you have one. It's really a moot point until you get it all hooked back up though. With the breather over your PCV port, I am relatively certain all that oil in the intake tract didn't come from there (unless it's been there a really long time).
So, with the PCV port vented to atmosphere, that still leaves us to figure out where all that oil in the inlet tract came from.
Lower intake manifold gaskets is my bet. Oil from lifter valley being pulled into the intake ports.
Not sure with FI, but with Carburetors the system is designed to have a vent in one valve cover with the PCV valve in the other, so it can draw in air from one side....
85GTStangGuy
Advanced Member
That's not how my factory carb'ed '85 was set up. The driver's side valve cover, which has the pcv valve, has a vacuum line from the base of the carb (or it may go to the carb spacer.... not sure offhand). The passenger side valve cover has a vacuum line coming from the air cleaner housing, with a little mesh filter inside the air cleaner. Both valve covers are under vacuum.
The hose from the air cleaner is where the filtered air is coming from thats being sucked into the system by the PCV valve on the other side....
Helped a guy with new engine problems once.. His brand new engine was making a screeching sound, he thought it was bearings and was getting ready to drop the pan to pull some mains and rods.....
He had a PCV on one valvecover and rubber plug on the other side... The PCV was creating a vacuum and the screeching was air being sucked in anywhere it could find a way to get in...... He should of put a venting type of cap on the side instead of a rubber plug...
Air comes in one side, goes throughout the engine ( including the crankcase) and is sucked into the intake or carb, thru the PCV valve, to be burnt.... No fumes or oil mist is supposed to escape to " harm " the air....
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85GTStangGuy
Advanced Member
Oh, okay.... didn't realize that. Since the air cleaner housing is under negative pressure, I guess I just assumed that air was flowing from the valve cover. Thanks for the education.
this system was adapted later, up till the late 50s a 'road tube' was used, a pipe installed just above the oil pan and hung down just below the engine with the end sliced at an angle, the air traveling under the vehicle would 'draft' past pulling a vacuum sucking the gases out of the engine, the first PCV system was used on WWll tanks to keep water out of the engines when crossing rivers and streams. Road vehicles started getting them late 50s early 60s.
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