jhblackwell
New Member
And, obviously, it doesn't happen to fans of mechanical engines.
Yellow oil sludge on oil cap
- Thread starter JeepKj03
- Start date
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JJsKJ
Full Access Member
I have an 04 and an 03 KJ, both on yearly or 10k mile change intervals running ASL 5w30 Amsoil. Neither of them has this problem. Both of them are driven mostly short distances during the week w/ only occasional long trips thrown in. The 03 has heavy duty cooling w/ the mechanical & electric fan. The 04 has regular cooling w/ only the electric fan.
MickityMike
Full Access Member
No! Way too many variables. But I do know that a fan won't make it colder, as that would be violating a law of thermodynamics. Ha.
But I can say that you wouldn't need a fan blowing for the outside air to be cooler than inside the filler neck, and voila! Condensation.
Now, I guess we could say that the fan could keep the outside air cooler (because it recirculates, not because it actually cools the air) for a short while longer than no fan, but I'd think the difference would be neglible as for as our mystery is concerned. I think ridenby probably has it right; pick one or more reasons from his post and then let's go shotgun a beer!
sleeve
Full Access Member
I agree on the beer.
And please - I hope my typing doesn't come off as angered. I'm simply after an explanation of the cause of this condensation.
For example:
My drive to Work, each way is 45Minutes long. [Long enough to reach operating temperature]
Oil = 5w30 Mobil 1 EP [year round]
Change Interval = 3,000 miles.
Yet - condensation...?
P.S. - I don't think I said the fan makes air colder. If my post read like that, than I apologize. I meant for it to read: the mechanical fan constantly moves air around the filler neck [most of the neck is exposed to the fan wash] thus lowering the temperature of the filler neck and keeping a constant stream of cold air moving across the plastic. This constant stream of cold (outside) air pulls heat off the neck and leads to the cause of condensation.
.
And please - I hope my typing doesn't come off as angered. I'm simply after an explanation of the cause of this condensation.
For example:
My drive to Work, each way is 45Minutes long. [Long enough to reach operating temperature]
Oil = 5w30 Mobil 1 EP [year round]
Change Interval = 3,000 miles.
Yet - condensation...?
P.S. - I don't think I said the fan makes air colder. If my post read like that, than I apologize. I meant for it to read: the mechanical fan constantly moves air around the filler neck [most of the neck is exposed to the fan wash] thus lowering the temperature of the filler neck and keeping a constant stream of cold air moving across the plastic. This constant stream of cold (outside) air pulls heat off the neck and leads to the cause of condensation.
.
My .02 cents:
During the week, I make a lot of very short trips. Some so short my temperature gauge doesn't even come to full temp before shutting engine back down. I live in a cool/cold, humid environment during the winter. Never have seen this phenomenon.
Not saying condensation isn't the problem, just wanted to throw my experience out there.
JeepKj03
Full Access Member
There are lots of variables in this. I like the theory of the mechanical fan but one would think that there would be no condensation once the engine warms up. Then liquid is able to evaporate again and be sucked into the engine. Maybe the condensation forms on the tube and then limits the amount of flow though the PCV system. May this allow the condensation to form and stick around? There are a lot of surfaces for it to stick with that baffling in there. It would be like a carburetor set up, you don’t want sharp curves or the fuel will condense in that area do to the slowing down of the air/fuel mixture.
MickityMike
Full Access Member
I suppose it's a possible cause - though I really doubt it.
Sorry to bring back an old post, but I think this problem pertains only to pre 2007 KJs, that reside in cold weather states. There is a fix, a TSB that replaces the oil fill tube and reroutes the pcv valve and hoses. If you have a front crankshaft seal that suddenly begins to leak during extremely cold weather, I would guess a frozen PCV system is the cause. My front crank seal suddenly started leaking, it was fine driving in town at low speeds, but getting out on the freeway caused leakage and left a small puddle on the garage floor. Did the TSB on the PCV system and leak has been gone for the last two months. Again it seems to be related to extremely cold weather, causing any moisure in the PCV hoses to freeze. The engine builds pressure at freeway speeds and forces oil out of the one seal closest to the oil pump, the front crankshaft seal.
Ry' N Jen
Banned
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We've been very fortunate.
We've never had that "Yellow Sludge" problem with our Rig!
We've never had that "Yellow Sludge" problem with our Rig!
J'sJeep
Full Access Member
What does TSB stand for?
The dealer uses TSBs Technical Service Bulletins to resolve customer complaints with problems which require some sort of reengineering of the vehicle. In this case an update to the PCV system used on 2007 and newer 3.7 litre engines. The TSB number for this update is2500108, the dealer will have the instructions and be able to order the parts for this fix. http://www.aboutautomobile.com/TSB/2005/Jeep/Liberty/Positive+Crankcase+Ventilation+(PCV)
rockymountain
Full Access Member
Changed my oil today. I mostly do longer trips with engine at operating temp for at least 10 minutes. I use mobil1 synthetic, not the EP. I had only a little bit if this snot in the filler tube. I also cleaned the pcv valve out with brake cleaner. I replaced it recently about 10k ago and it was as bad as the one I replaced then. Make sure the pcv valve is free and not sludged up. If you shake it the metal slug or whatever it is should freely move around.
Yes but if complete this TSB, it wont be anything to worry about anymore. It eliminates the pcv valve in the filler neck and relocates it to the drivers side cylinder head. It eliminates the y junction and 2 tubes, and replaces it with a single tube going from sponge bob in the air cleaner housing to the passenger side cylinder head. very simple and effective, our Jeep makes shorter trips and there is nothing in the oil fill even when pulling out the baffle. I did it to eliminate the possibility of another pcv freeze up which causes engine pressures to cause oil leaks
rockymountain
Full Access Member
Sounds like a good mod. Your link may be broken. It would be nice to have the parts list to get it done.
I work for Mopar parts division of Chrysler LLC and I had to call a dealer to get the instructions and parts list off of Dealer Connect, a system I have no access to. All the links on the internet, like the one I posted charge you for the info
rockymountain
Full Access Member
Ok then. It's time for pics. Maybe it can be duplicated.
2004 and have never had an issue with the sludge
of course I take mine out and run it, don't give it any slack and it gets warmed up good every trip.
166,500 on it so must be doing something right
of course I take mine out and run it, don't give it any slack and it gets warmed up good every trip.
166,500 on it so must be doing something right
