Engine Burning Oil

[Patcon]

Lets start with causes of high pressure

Problem with the oil relief

Bearing clearances

Excessive pump output

What is the engine history? Have you ever run any oil flush through it? If you haven't,  don't!

My first concern would be junk building up in the bearings driving up oil pressure.  Oil relief could also be a problem

[jonbill]

Perhaps:

There was an incident in the engine that blocked something that drove oil pressure up.

That caused something else to deliver oil into the combustion Chambers, even after the original high pressure incident is resolved.

 

I can't imagine how high oil pressure could damage valve stem seals or oil control rings.

I can imagine high oil pressure might damaging the head gasket and leak oil into a couple of Chambers, but hard to think how that might make all cylinders equally sooty.

 

 

[240dkw]

20 minutes ago, jonbill said:

 

 

I can't imagine how high oil pressure could damage valve stem seals or oil control rings.

I can imagine high oil pressure might damaging the head gasket and leak oil into a couple of Chambers, but hard to think how that might make all cylinders equally sooty.

 

 

The head gasket idea is what drove me to take the head off, but I can not find anything wrong with it. 
It has about 600 miles on a complete rebuild and has been running awesome with no problems until this one.

[Zed Head]

39 minutes ago, 240dkw said:

Captain: Sorry for the confusion, jonbill is correct. It has been running great, but with high oil pressure for about 100 miles or so. Then I checked the relief valve, all good with no modification. Started it up again and still had the problem.. Shut it down, installed gauge started it up and pressure was good at 61 psi.

Shut it down and installed a new pressure sensor I had. Start it up and reading was good

Could be that the guage in the dash wasn't reading right.  It seems possible that the oil pressure was never really too high.  When you installed the gauge on the engine block you disconnected the dash gauge.

The high oil pressure reading might be a coincidental distraction from the real problem.

[Patcon]

If the engine is fresh, then high oil pressure wouldn't concern me too much. I rebuilt a chevy that did the same thing because the mains were on the tight side. I dont know how too high is a problem unless it gets to 100 psi. Then the oil filter can be at risk. What weight oil were you running?

[Datonedatsun]

4 hours ago, Captain Obvious said:

Valve stem seals and/or guides have no effect on oil pressure. Can have impact on consumption, but not on pressure.

So just to make sure I understand the issue.... Car had been running great. No problems. Then one day, all of a sudden your oil pressure started running way higher than it used to, and you started blowing blue smoke?

Only reason I suggested those two is because he said all the spark plugs are fouled with oil... those would be the most lightly culprits for that to happen 

[Datonedatsun]

There Is a possibility that you could be running way too rich? But you would be able to smell that, it can cause black grime on the plugs and blue smoke but pretty improbable that, that is the reason.

[Zed Head]

14 hours ago, 240dkw said:

It would get over 80 psi when up around 5000 RPM, it followed the engine speed 40-45 at idle and up to 80+. The "problem is a rather large amount of smoke coming out the pipe. I do believe the high oil pressure caused something to happen.

It might help to get in to the basics of the engine and its lubrication system.  There is no "pressure" that would force oil in to the combustion area.  High oil pressure might lead to high oil volume, flooding the top of the cylinder head, but there is plenty of room for the oil to flow back to the crankcase.  You could have excess oil flowing through the main bearings, splashing up n to the cylinder walls as it gets thrown off, but the oil scrapers would have to be seriously overwhelmed to have that oil get ni to the combustion area.

In short, oil pressure and smoke from the exhaust are not connected.  It's actually more likely to see low oil pressure and smoking on a worn engine, with worn valve seals, than on a low mileage engine with high pressure and good valve seals.

The two problems could be coincidental but there's probably no cause-effect relationship. 

[240dkw]

3 hours ago, Zed Head said:

Could be that the guage in the dash wasn't reading right.  It seems possible that the oil pressure was never really too high.  When you installed the gauge on the engine block you disconnected the dash gauge.

The high oil pressure reading might be a coincidental distraction from the real problem.

I did start there as well, I used a variable resistor and walked the gauge up and down the scale and it is working correctly a few days before this happened. 
I do not disagree with you as a coincidental problem. 

[Mark Maras]

  You describe the black soot in the cylinders as oily and yet I don't see the oil sheen in the pics. The pics look like sooty cylinders from running too rich. Stick your finger in the tailpipe and take a sample. Is it reasonably dry black soot or is it wet, oily black soot? I'm leaning toward no oil pressure problem (new engine) and it's running extremely rich. Also the fact that it started running lousy in short order rather than gradually getting worse, like fouling plugs do, seems like this is a mixture problem. That said, the oil pressure is something I'd keep an eye on.

[Zed Head]

16 hours ago, 240dkw said:

#1 - 158
#2 - 159
#3 - 160
#4 - 160
#5 - 158
#6 - 157

I then did a leak down test
#1 - 100/92
#2 - 100/94
#3 - 100/92
#4 -100/94
#5 - 100/81
#6 - 100/80
I can hear the air leaking somewhere on both 5 and 6
So I pulled the head off.

So, "now what?" is the question.  

[Dave WM]

how about this oil pressure a non issue, sudden consumption on freshly rebuilt engine from a valve stem seal that has popped off?

Did we try the high vacuum (down shift while throttle closed) run then suddenly get on it for a cloud of blue smoke after sucking in oil during high vacuum?

I would be tempted to pull the valve springs off and at least check to make sure they are all seated.

Edited August 9, 2019 by Dave WM