Lost my 3.0L PCV/Filer/Cap thing

[jangell]

I changed the oil in my 3.0L the other day, and used the PCV (I think that's what it's called?) thing on the passenger side valve cover. I was going to use the filler on the driver's side valve cover until I realized that while the A/C line clears the cap, it isn't actually possible to remove the cap with the A/C installed.

In any case, I forgot to put the cap back on. I then drove around for a bit and noticed a high idle. When I got home, I found that the cap was gone, and the vacuum line it was hanging off of still firmly attached to the engine and sucking in air.

I still had the 2.8L filler thing, so I put that in instead. I thought this would be fine, but it's not. You can clearly hear air being sucked in through the vacuum line, and I still have the high idle problems.

It seems to be difficult to find the 3.0L thing to order a replacement, in part because I have no idea what it's called. The 2.8L fits in the valve cover, but either it is incompatible or it is plugged up and isn't letting enough air pass. Do these things get plugged up? I'm betting mine is original, so it wouldn't surprise me. The design is different from the 2.8L vs. the 3.0L; instead of the single-piece filter-like setup of the 2.8L, there's a "three discs on a shaft" setup with a separate cap on the 3.0L. I assume this lets more air flow from the engine and is why the 2.8L cap isn't working?

I have a broken 3.0L cap (from when I transported the engine and didn't pay attention to where the ratchet strap ran), but only the bottom part of it; I seem to have lost the top part, so I can't glue it back together.

So my questions are:
- Does anyone know what this cap is called on the 3.0L?
- Does anyone know where to get it?
- Should the 2.8L be compatible with the 3.0L?
- Is my 2.8L cap just plugged up? Is that a thing that happens?
- I assume this exists for a reason, and that just plugging the end of the cap isn't recommended.

Thanks!

-- Joe

Napkin 3 08-25-19, 12.27.16 PM.jpgNapkin 3 08-25-19, 12.28.35 PM.jpg

[David T]

Parts Manual section 1-4-0 fig #8 pn 102145 it is called Oil Filler Cover. When the "O" ring is bad the cover fits very loosely, maybe all you need is a new "O" ring. You might be able to find one locally.

[jangell]

The old 3.0L was loose, but the 2.8L is very, very tight in the valve cover, so I think the O-ring is OK.

-- Joe

[David T]

The crankcase ventilation is very tightly calibrated. There is no PCV valve like most ventilation systems. There is an orifice that calibrates how much vacuum is used, it is in the Aux air pipe that holds the CSV. The oil cover for the 3.0 may have a different calibration than the 2.8, I don't know. You could try blocking of the vacuum and see if that brings down the idle. Because you have a 3.0 I don't know what you have or don't have relative to the 2.8. I don't know how your vacuum is hooked up to the oil cover.

[jangell]

Thanks. I find that capping the vacuum (via the outlet on the "cap") with my finger did bring the idle back down. I could do that permanently, but I'm not sure I really should. The vacuum is connected from the side of the intake manifold into the top of the the "cap", rather than to the CSV. The other end of the hose is just open to the air, though; I don't have a line running back to the cold air intake, although I probably should.

-- Joe

[David T]

You really do need to ventilate the crankcase to avoid the build up of moisture. Find some way to hook something up either like the 3.0 or the 2.8. On most V-6/8 motors they suck from one valve cover and let the other breath air in.