Oil burn cloud on engine deceleration

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So it sucks the oil up through the meeting point of the intake, head, crank case?

The smoke is white. Smells smoky and not sweet.
AJ/FormS said:
You said 2 breathers and no PCV was ok. Were the valve covers all oily under and near those two breathers?
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one breather was filled with oil all the time. Would drop it down on to the heads and smoke.
 
Well if it is truly white then that changes the game, smokie or sweet smelling or not! Which, what it is really!

Starting to sound like a if you can guess it in a hunting game with too may variables! I am out with getting some more specifics!
 
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WSUTARD said:
I guess I don’t understand how the intake can introduce oil. What am I missing?
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this may not be your case, but consider this: a guy wants to reduce his chamber volume, you know, get more compression, so he cuts the heads, say 0.060". The intake surfaces on each head are now closer together, so the intake is now sitting higher on the engine. If you have other factors, like thicker intake gaskets, it can even add up to the the bottom of the intake ports not sealing properly, and you may even be drawing in air/oil from the cam valley. You throw in uneven cuts on heads and/or intake and you can have angular mismatches on the intake sealing surfaces.
I bolt the intake directly to one head, no gasket, and use feeler gauges to make sure there is no angular mismatches, both longitudinally and laterally across the other surface.
 
Quick check to see if you have internal vacuum leaks (either valve guide or ports into lifter valley): With engine at idle and PCV system hooked up, remove breather cap from opposite valve cover and plug hole with thumb. You should feel vacuum build within 1-2 seconds, and become quite strong. If the idle speed or quality changes even a little bit, you have an internal vacuum leak of some sort. If vacuum does not build, or if there is pressure at idle your rings have failed.
 
I would definitely rethink the idea that it's burning oil if the smoke is white. Oil smoke should be blue...
 
Had the same problem many years ago on a 340 when incorrect intake bolts were installed. They had shoulders on them. This prevented proper clamping of intake to heads. The intake ports sucked oil from the valley. It really put a James Bond smoke screen to shame.
 
Today I tested to see if it was coolant today. Pulled some out till it was at the first level in my radiator. Took it out for a run, got it smoking really good on three downhill decelerations. Coolant level didn’t change.

It’s really hard for me to see the smoke but I swear it has a very light blue tint to it, but my car is blue who who knows if it’s just picking up that color. My buddy swears it’s white. However, the smell is definitely not coolant. It actually smells like the crank case vapors.

Speaking of, on my last downhill I had lots of smoke coming out the engine bay, drivers side and I think it blew out the breather.

I use ARP intake bolts. Pic below.

I will try the internal vacuum test to see what happens.
image.jpg
 
C130 Chief said:
Quick check to see if you have internal vacuum leaks (either valve guide or ports into lifter valley): With engine at idle and PCV system hooked up, remove breather cap from opposite valve cover and plug hole with thumb. You should feel vacuum build within 1-2 seconds, and become quite strong. If the idle speed or quality changes even a little bit, you have an internal vacuum leak of some sort. If vacuum does not build, or if there is pressure at idle your rings have failed.
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At idle there is no vacuum when I cover the breather hole with my palm. The idle does not change.
 
WSUTARD said:
Looks like I’m going to be changing the intake gaskets this weekend. Again.
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if and when you pull the intake, make sure you drain sufficient coolant, so you can be careful when you remove intake, you don't spill a lot of coolant, because you need to examine the gaskets and intake ports, and be able to read what problems may be there.
 
I see your manifold has provision for egr, though you've plugged the exterior ports. Is there a hole in the intake plenum floor? Did you tap and plug it, too?
 
WSUTARD said:
I just pulled the breather and it’s soaked with oil.
View attachment 1715098026
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the picture of the breather soaked with oil, makes me think you need better baffling and/or you're blowing oil out the breather, instead of the breather filtering out incoming air to circulate thru engine and be sucked out of the pcv valve. I can't remember, have you run a compression check and rechecked it with a squirt of oil?
 
I haven’t run a compression check in a while. I will do that this weekend before I pull the intake.

When I ran two breathers the passenger side would end up soaked and the drivers side would be dry. Now that I have the PCV on the passenger side the driver is now getting soaked.

My engine has always had low vacuum levels at idle.

Maybe I should run PCV on both sides?
 
Why not temporarily fir OEM valve covers and PCV system while you troubleshoot. The factory stuff may not have been sexy, but it worked as well or better than most aftermarket stuff.
 
70Duster440 said:
Had the same problem many years ago on a 340 when incorrect intake bolts were installed. They had shoulders on them. This prevented proper clamping of intake to heads. The intake ports sucked oil from the valley. It really put a James Bond smoke screen to shame.
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I chased a very similar issue the OP is experiencing. Changed PCV, Breather, valve seals. Ended up being the intake gaskets like 70D..said. I checked and had oil trails from the valley down the runners. Changed the gaskets and resealed bolts. Issue gone.
 
Just finished my compression check. Here are the results as well as a pic of my spark plugs. Closest row, right is #2.

Dry is first, Wet is second
1 - 148, 157
2 - 139, 148
3 - 135, 145
4 - 130, 149
5 - 139, 149
6 - 130, 146
7 - 144, 157
8 - 140, 151

EF6FB73A-34B7-4B5B-92F8-A3063081C41E.jpeg
 
Ok, what do you guys want pics of? I removed the intake. Looks like a ton of oil on the gaskets and intake surface.

7425ADC4-BDE6-4E4E-A21D-AB37B6BE37FE.jpeg
E0C7D260-136B-4C4A-989F-9713AD465428.jpeg
 
Ok, what do you guys want pics of? I removed the intake. Looks like a ton of oil on the gaskets and intake surface.

crewchief said:
Mine was the same way when i pulled it. What oil did you see on the head side? Shows the intake is very wet.
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I haven’t pulled the gaskets off the head yet. Was waiting for pic requests. Also, birthday party to go to.
 
For now go to the party, put engine on hold for tonight.
 
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