Ugly Stuff on My Oil Cap

[twentynine]

Yesterday I changed the oil and filter on my 2004, 5.7L Hemi. When I popped the fill cap off, I found some moisture, actually what looked like beads of condensation and some built up rust looking stains.

History: I purchased the truck new in August, 2004. Presently it has 24,500 miles. The truck is used as a daily commuter and to tow a 3500# Boat, motor, trailer. Daily commute is 12 miles one way, stop and go . Towing service is maybe 500 miles between each oil change. The oil and filter has been changed every 3000 miles. I have used Motorcraft syn-blend 5w30 most of the time. However this summer I swithed to Supertech 10w30 full synthetic. Filters have been a mix, Mopar, Wix, and Advanced Auto. I have had no engine related problems with this truck. Present fill is Motorcraft syn-blend 5w30.

When I popped the oil cap yesterday I noticed the condensation and then the rust looking deposit. The deposit is not hard like rust, it has a very thick plastic feel to it. One other thing I noticed, was smell. The oil cap and the oil coming out of the engine had a very bad odor, kind of like the smell of old oil in a junk yard. Only had 3100 miles on this OCI.

What is this junk?

I am going to attempt to attach a photo of the inside of my oil cap. If I fail please nobody laugh. Here goes!

 

[Tones]

I would agree that it was condensation except for the smell. When I changed my oil with a coolant leak, I could tell by the smell that something wasn't right. I will never forget that smell.

Have you noticed any drop in the coolant reservoir? It is a bad time of year to try to judge because the cold weather will cause the reservoir level to change, but keep an eye on it.

 

[twentynine]

Coolant leak, blown head gasket was my first thought. But no loss of coolant no gain in oil level. Oil draining out of the engine was the same color it always is. Except for the smell no difference in oil..

 

[Captain Howdy]

I'd vote condensation. I noticed it on my oil cap while topping up after changing the filter.

 

[bruce381]

I'd vote condensation also if cap is plastic residue is water soluble minerals leaveing a deposit upon evaporation if cap is metal then rust from condensation. Most likley NOT an issue motor oil will get blowby and moisture in it, it is normal BUT have a UOA,s done with the eye toward a coolant/gycol leak and then you will know for sure anything else is a guess. or check crankcase PVC system for a clog.

bruce

 

[toocrazy2yoo]

Condensate? The cap gets cold while the warm fumes are still floating around underneath?

Just guessing, but that may be pretty common in the wintertime, assuming you're in a cold weather clime..

 

[speedtc]

It's condensation. In the summer you will not have it. I had a 2003 dakota 4.7 with this issue. I hat white foamy looking residue on the bottom of the oil cap. The rusty looking color i did not have though.

 

[Tim]

My brother in law's hemi cap looked the same when I helped him on a Castrol Syntec 5,000 mile change. He had more of the orange crud, though.

I recommended either fewer short trips or shorter OCI. Turns out my sister had been using the truck for work related stuff that involved both short (
FYI they are not in Houston, they are in VA.

 

[KJA426]

The 4.7 Dodge is notorious for condensation inside the filler cap. It usually only happens in winter and they changed the cap design a few years back.

 

[Black Thunder]

i wouldn't worry about it.

i get some condensation on my oil cap once awhile every winter...thats the only time.

 

[Geno]

Here in Wisconsin its normal for winter driving - unless your making only long trips.

 

[adam123]

Its pretty much normal shouldnt do any damage almost all of Chryslers engines do that My dad Had a 318 Motor that would do the same thing only excesively and that engine made it all the way up to 400K before the body gave out to rust.

 

[T-Keith]

It's much much worse on the 4.7s. It's common in many engines, especially with large plastic caps.

 

[Dark Jedi]

yeah its common because the filler neck is plastic and on the 4.7 its out in the open. I dont know how the hemi neck are. but I was told if you insulate the neck it will stop it. all I do is just wipe it all out. the bottom of my oil cap looks like that. its a 03 dakota 4.7.. so dont worry and just clean it out with a rag and enjoy the hemi

 

[thunderchild]

Dark Jedi is correct. I have a 4.7 Durango. 2nd one actually. Both 4.7's did the same thing. it is caused by condensation in the filler tube. It's harmless.

 

[mikemc]

You could do a used oil analysis to check for coolant and then you would know for sure.

 

[adam123]

My 4.7 does this as well. Heres a link to the Oil analysis for it No coolant or moisture was present in the oil.

Click Here

 

[Dark Jedi]

of course I am correct lol. just make sure your wipe it all out before pouring new oil in. adam nice UOA. when I get about 3000 I will get one done on my 4.7.