I highly doubt it but I thought I would ask. In the 400 miles Project Impossible has been back on the road I saw this morning that it was a full quart short of oil, and it's been having a clear smell of oil after its been on the road a bit. I was looking around for external oil leaks tonight when I got home from work, and didn't see any. However I did see a ring of what turned out to be fresh oil around the PCV valve where the grommet is.

PCV grommet w/ fresh oil

Since this is my first time with an Oldsmobile V8 I thought I would ask if this is normal, just in case it is. Otherwise it would seem to be pulling up a large amount of oil somehow. The PCV valve itself is new (ACDelco from Rockauto), I had an issue with random hot idle stalling early on that it solved. I also replaced the breather on the other side just because the original was dirty. Otherwise I haven't done anything else to the PCV system. The valve covers are original. Could it really be pulling all that oil and causing it to "lose" that much oil?

 

If you smell burning oil and you just replaced the PCV valve I'd think your oil loss is through the valve guide seals or the rings. For an Oldsmobile engine to be a quart low is quite a bit. I only ever have to add that much to my 71 98 when it's been sitting way too long.

Does your Oldsmobile puff bluish smoke at start up that fades away when the engine warms up? If so, that's a classic sign of worn valve guide seals. You can check the rings with a compression test.

 

Well just because it's replaced doesn't necessarily mean it's good or the right one. I still wonder, given how tight of a press fit the valve is into that grommet how can there be so much pressure to push up oil between the valve and the grommet? Has your 71 ever done that?

I haven't seen any blue smoke at all, just regular white condensation. I'll have my friend stand next to the tail pipe this weekend when I start it for a closer look but I'm skeptical he'll see anything. I plan to do a compression test this weekend. Would there be other signs of worn valve seals? Like wouldn't that show up on a vacuum gauge?

 

There really should not be any pressure to push oil out of that spot. Looking at your picture it looks like it is just barely seeping if any. How tight does the valve fit in the grommet ? The grommet looks like it has been on there quite a while so it might just be hardened up.

 

Signs in particular of bad valve seals are excessive oil consumption, blue smoke on a cold startup that goes away in 5-10 seconds and oil fouling/buildup on the spark plugs particularly when it favors one side of the ceramic insulator. The wrong PCV valve can cause a lot of oil consumption. Pull a valve cover and check for clogged oil return holes in the cylinder heads.

 

True it seems to be seeping. The grommet isn't new, no idea how old it is. It was quite a fight to get the old valve out and put the new one in. I had to resort to tapping it in (as gently as I could) with a rubber mallet. But if it's getting into the grommet, wouldn't it also be getting into the valve itself?

Sounds like that's something I should do this weekend regardless of what other issues it may have, I didn't clean the oil returns. I will also do a compression test.

Valve work is time consuming and expensive, I want to make sure that's a problem before doing it. Since I haven't seen clouds of blue smoke I'm thinking the issue is something else.

 

If the PCV valve had to be tapped in with a rubber mallet.
Then the grommet is probably hard as a rock, and maybe 50 years old.
It probably cracked, and that's why it's leaking.
Fusick has new ones;
https://www.fusickautomotiveproducts...p?number=VC104

 

Certainly does need replacing.

 

Usually, when a PCV goes, the trouble is oil consumption as opposed to a leak since the baffle in the valve cover is often removed by the people of the land; the common clay of the New West, and it sucks up oil.

 

Note that the PCV grommets are actually just common Dorman parts. Dorman 42314 and 42067. No need to pay specialty prices for them.

 

I had someone else start it up today while I watched the tail pipe, looks like there was some blue smoke at startup. While I'm not totally sure the PCV system is functioning perfectly either, I've seen enough to point a finger at the valves. Time to pull the heads.... :/

 

The heads can stay on the car to replace the valve seals. Do a compression test before pulling the heads, if the compression is good you can leave the heads in place and replace the seals.

 

^x2^ What he said.

 

I don't have the tools to do valve work and it's entirely possible the guides are worn too, which I wouldn't be able to deal with for sure. I was intending to have a machine shop deal with it.

 

Valve seals are easy to do with heads on and not critical in the first place. Ok, it will smoke for 30 seconds after sitting a while, who cares?

 

It is a lot more work to pull the heads and take them to a machine shop and yes it is possible the guides could be loose. I'd do a compression test first to know what is going on inside the engine.
Tools...in addition to common hand tools, a valve spring compressor an air adapter and an air compressor are all that are needed. Rope can even be substituted for the compressor.

 

Got the heads off and into the machine shop. Not only are the seals bad the exhaust valve guides are pretty much all toast, I wasn't given numbers but they were really far out of spec. Think we found our oil leak.....

 

At least you figured out your culprit. Let us know how the heads go back on.

 

Sure thing, planning that for early next week. A question I have, the block wasn't as drained as I thought and while the vast majority of it went off onto ground some small amounts splashed onto the pistols and into the valley. It was vacuumed and mopped up, but should I change the oil or is a small amount of coolant not going to hurt anything?

 

Even a little coolant in the oil is a dangerous thing.
Draining the oil and filling it with new oil is the best insurance against disaster.