Clogged PCV tube

TJM did pass the time by typing:

Yep, icky.

That won't cause an oil leak, just excess oil on your air filter. No reason to use dye.

So the excessive crankcase pressures are just a myth? I've perused some websites that seem to indicate long-standing PCV cloggage can cause massive oil leaks anywhere it can find a way to escape. The only leakage I've seen so far is around the outside of the oil dipstick tube.

TJM did pass the time by typing:

Myth, no, not rilly. Usually those leaks happen around the valve cover.

The I6 uses CCV or Continuous Crankcase Ventilation, not PCV or Positive Crankcase Ventilation. The excess pressure is what was sending oil out into your air filter. Now if both holes got plugged you start to see oil and dirt build up around the dipstick.

Truly excessive crankcase pressures are usually caused by a bad valve guide allowing exhaust gases into the valve cover. That can be enough to pop out the dipstick or even the vent hoses.

You probably have a good amount of crud built up on the valve cover. If it's leaking this would be a good time to take it off, clean it out, and reseal it. If too much crud builds up in there it can break off and clog oil passages. Generally, looking at the underside of your oil cap will give an indication of how bad things are. If it has big clumps you should consider removing the valve cover and cleaning it.

I'd probably step up oil changes to 3000 miles for the next couple times just to clean out what may be trapped in there. No need to use engine cleaners right yet as those tend to loosen the big chunks and cause more problems.

I checked the oil cap and it has a fair amount of "oily crud" on it, but not sure if I see any "clumps". Then again, I have never taken the time to grab some paint thinner and clean the oil cap, so I imagine its just 143K worth of "crud buildup". I guess the only way to really find out is to take off the valve cover and have a look-see for myself. Taking off the cover looks relatively painless....any pitfalls I should be aware of? Also, how do I re-seal it.....RTV and/or a gasket?

I had a change about 2500 mi. ago, so I will take your advice and change every 3K for a bit.

TJM did pass the time by typing:

It uses a form-in-place gasket that should be reusable if it stays in one piece. All you need to do is skin another coat of Permatex or similar RTV sealant, fill in any gaps or cracks, and put it back. If the gasket material comes off or is in real bad shape you will have to lay down another bead. Jeep sells the gasket material but I've used the stuff from NAPA with good results. Just follow the directions and make sure the surfaces are clean of oil (wipe with alcohol). The nuts/studs only go down to 75 in.lbs. Make sure it's an even bead otherwise you will get leaks. (that's the tricky part)

No, excessive crankcase pressures are not an urban legend. It usually goes along the lines of a leaking rear main seal, which you fix, then a week later the front crank seal, which you fix, then a week after that, the valve cover gasket, which you fix, but by now you realize that the clogged PCV is the root cause of all of your problems, and you fix that, too. Ask me how I know.

Jerry

In news:40a18609 snipped-for-privacy@newspeer2.tds.net, Jerry Newton from was injured because:

So, umm, Jerry, how do you know??? ;)

I just want to say "Thanks for the information", as mine was clogged 99.99%

Dave