Engine time

[Zed Head]

You went from "don't want to turn the engine over" to "drive it up and down the road"?  Sounds like something I'd do.

We're still guessing but it seems like the focus should be on where the excess oil is coming from.  Head gasket still sees reasonable. Combustion gases pressurizing the crank case, blowing oil vapor through.  Maybe.  

At least it's not a path of destruction problem.  Something happened but it seems stable.  That's usually a good sign.

[Stanley]

Finally got to take time off work today (being your own boss doesn't make it any easier) and work on the car. Hadn't driven it for over a month. Pulled the hose off the PCV valve and clamped a silicon cap over the valve just in case. The plugs all still had oil on them so cleaned them off with a shot of carb cleaner. Car started OK, a little smoke at first but then OK. Drove it up on the ramps and changed the oil and filter. No water in the oil.

Took a drive to the grocery store, about two miles, didn't notice any smoke (side mirror is dirty though) and the car seemed fine. Driving back there was a good bit of smoke. Could smell the oil. At one point, at low rpm, heard the rattling sound that lasted about two seconds. Otherwise the engine sounded OK.

So, happy for a few minutes, then sad. Not too sad though. New engine getting built, should be ready in a few weeks.

[Stanley]

This is bugging me. Maybe the engine need to be warmed up before it smokes. Didn't see it on the way to the store yesterday. The engine was running smoothly. No roughnes or miss that would indicate a misfire.

I'd forgotten but in my first post I mentioned smoke coming out of the air cleaners (K&N's). Don't remember if it was while driving or after I shut off the engine. I didn't see that yesterday. It seems like if an intake and exhaust were both partially open and the engine is off, so no vacuum, then smoke from oil in a hot cylinder would come out the air cleaner. So maybe that's not relevant.

I'm pretty sure nothing could happen to a head gasket that would cause oil to get into every cylinder but not let any coolant get into the crankcase.

The crankcase vent is not connected to the air cleaners, and the hose from the vent to the PCV is now disconnected. No oil came out of the hose while driving. The cam cover vent is not connected to the air cleaners or balance tube. It has a hose that dead-ends in front of an air cleaner. No sign that oil came out of it.

The rattling sound that happened once yesterday sounds like the rattle when the engine overruns when it's shut off, but it only happened when driving and the engine seemed to be be running normally before, during, and after.

I want to take another test drive watching the vacuum gauge for anything odd, scared of getting an expensive "gross polluter" ticket though.

[7tooZ]

Can someone help me understand what the issue is here. Spent sometime reading back through this.
Isn't white exhaust (sounds pretty heavy) caused by water in the combustion chamber????
If so I would think that if enough water is in the combustion chamber there would be other odd noises too?

Possible crack in the head or block that introduces water once pressure builds in the cooling system?
Thoughts??


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[Stanley]

Not water, oil. Inspection of plugs shows fresh engine oil on each plug. Smoke smells like oil. Changed the oil yesterday; no water in the oil.

[7tooZ]

So I am thinking that you are putting water into the combustion chamber it is getting burned. So possible a small leak and only under pressure when cooling system is hot.
Two things to try see if your local parts store has radiator pressure tester and check it while hot to see if it loses pressure
Or
Pull the thermostat and radiator cap and run it when there is no pressure on the cooling system.

My thoughts from a backyard mechanic


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[Zed Head]

4 hours ago, Stanley said:

Not water, oil. Inspection of plugs shows fresh engine oil on each plug. Smoke smells like oil. Changed the oil yesterday; no water in the oil.

So the question of which side of the rings the oil comes from remains.  If it's coming from the intake side that can really only be the PCV hose.  If it's coming from the other side of the rings, direct from crank case, it kind of implies broken rings.  Seeing it in all cylinders sounds more like PCV hose.  But you said you blocked the PCV.  And the odds of breaking six oil scrapers seems small.

So here's a new one - how about the valve seals on the intake valves?  If they went bad for some reason you'd suck oil down the valve stem and in to the intake runners.  If your engine was built to a high consistency it would be reasonable to assume that the same part would fail around the same time for all six cylinders.  Maybe the first high rev you did or similar.

[Stanley]

Right, the oil can only come from the top or the bottom. The cylinder head was new looking 6 or 7 years ago when I got. It's from 1980 so I figured it had been rebuilt or at least had a valve job.   After it was installed the engine quit using oil. I'd like to know the story of it but only have what I was told. Anyway I doubt if all the valve seals (or oil rings) would go out at once.

As far as I know, the only thing that connects all the intakes is the balance tube. Suppose one cylinder got oil in it from whatever source, and there was a backfire or overrun, maybe the balance tube would then distribute oil to all cylinders. I read that the engine can run backwards when it overruns. IIRC there was an overrun when I stopped before the first time it blew the cloud of smoke in July. No backfire or overrun yesterday though. The amount of smoke while driving is irregular, not steady, like a bus that doesn't smoke until you get right behind it.